Modeling hydrologic alteration in Northern Gulf Coast river basins

Proceedings of the 2023 Mississippi Water Resources Conference

Year: 2023 Authors: Roland V., Crowley-Ornelas E.

In recent history, interest in the conservation of riverine ecosystems has grown as people have become more knowledgeable about the functions of these habitats. Anthropogenic hydrologic alteration is a direct threat to the health of these ecosystems because it often triggers a range of negative effects on the biological, physical, chemical, and hydrologic characteristics of impacted waters. Understanding important factors and drivers of hydrologic alteration is essential to the planning effective conservation action plans. This study explores the application of machine learning to predicting hydrologic alteration and identifying important predictors of hydrologic alteration in the Pearl and Pascagoula River Basins in Mississippi. Modeled daily streamflow for 12-digits hydrologic unit code (HUC12) watershed pour points was used to compute the net change in streamflow volume and to conduct a confidence interval hypothesis test across pre- and post-alteration periods between 1950 and 2009. Cubist models were developed for each basin to predict the p value of the confidence interval test as a function of the net change and a range of other physical and meteorological watershed parameters. Analysis of the net change and confidence interval test results indicated the basins had similar amount of altered HUC12 watersheds. Moreover, patterns of altered watersheds tended to coincide with the locations of densely populated areas, dams, and in areas with substantial land cover change in both basins. The cubist models developed for the basins produced accurate predictions of the confidence interval test results in most HUC12 watersheds. The importance of model predictors demonstrated differences in the relationships between basin geomorphology, land cover, and hydrologic alteration in the basins. The results of this study are evidence of the potential of the cubist algorithm in hydrologic alteration assessments. More broadly, machine learning and other data driven approaches can be applied to a variety of complex water resources issues to inform local, state, and federal resource managers.

Microplastics in the Mississippi River and Mississippi Sound

Final Report

Year: 2020 Authors: Cizdziel J.

Led by consumer products, the worldwide demand for plastic continues to grow with global production at nearly 350 megatons in 2017 (Plastics Europe 2018). Unfortunately, careless discarding of plastic and mishandling of the plastic waste stream has resulted in widespread plastic pollution, including the infamous oceanic garbage patches (Lebreton 2018). Further, plastics in the environment weather and degrade as a result of ultraviolet radiation, microorganisms, temperature changes, and mechanical forces (e.g. wave action), yielding smaller and smaller particles called micro- and nano-plastics. Here, we focus on MPs, which have been described as "any synthetic solid particle of polymeric matrix, with regular or irregular shape and with size ranging from 1 ?m to 5 mm, of either primary or secondary manufacturing origin, which are insoluble in water" (Frias 2019).

The occurrence of MPs in the aquatic environment is well documented, with higher concentrations generally found near population centers (Li 2018). MPs have also been detected in remote areas, including the Arctic Ocean (Lusher 2015), deep-sea sediments (Free 2014), and mountain lakes (Cauwenberghe 2013). Given their small size and ubiquitous nature in lakes, rivers, and oceans, their ingestion and impact on aquatic life poses a serious threat, particularly for small suspension-feeding organisms (Auta 2017). Moreover, MPs have been shown to be substrates (vectors) for other contaminants, including persistent organic pollutants such as dichloro-diphenyl-trichloroethane (DDT), both in laboratory studies and in field studies (Teuten 2009; Costa 2017; Tourinho 2019).

Unfortunately, there are often wildly different estimates reported for MP abundances in natural water, even from the same waterbodies, making meaningful comparisons difficult and hindering the utility of real-world MP surveys (Lusher 2017; Lenz 2018; Jiang 2018). Some of these disparate results may be due to inherent variability at the sites, but part of the problem may be the different sampling, sample preparation, and analytical methods used. On one hand, the wide range of approaches to MP analyses is not surprising given that MPs (1) are a diverse class of contaminant encompassing a wide variety of sizes, morphologies, and chemical and physical properties (Rochman 2019), (2) partition into different environmental compartments depending on size, density, biofouling, and other factors (Hartmann 2019), and (3) have only recently (in the last decade) caught the attention of the larger scientific community. On the other hand, MP analytical methods need to become more harmonized to increase the quality and comparability of experimental data.

Two common ways to sample plastic debris suspended in water is through use of a surface or subsurface tow net or by collecting a known volume of water at a specific location (bulk water sampling). Nets are typically used in investigating large areas with results being reported in particles/m3, whereas bulk water sampling is more accurate as a snapshot and is often reported in particles/L. A major drawback to sampling with a net is that it fails to capture particles smaller than the mesh opening (typically 333-?m), and these smaller particles tend to be the most abundant. In contrast, bulk water sampling captures all size fractions of particles in the water. Another advantage of bulk water sampling is the elimination of contamination from sampling equipment such as nylon nets and ropes. However, trawling with a net or bulk water sampling should be considered complementary techniques, covering different parts of the overall MP pollution (Tamminga 2019).

When using a net, the plastics caught in the cod end are typically rinsed out into a container for later processing in the laboratory. Determining the volume of water passing through the net or being pumped through collection sieves is important to accurately calculate MP concentrations. At some point the net and bulk sampling methods converge with the samples being filtered through a sieve or series of sieves to isolate particulates by size fraction(s). Larger particles can be removed by tweezers and analyzed by FTIR or other means. If the remaining solids collected on the sieves or filters are organic-rich they are typically subjected to either enzymatic digestion (Cole 2014) or wet peroxide oxidation, the latter sometimes in the presence of a Fe(II) catalyst (Tagg 2017), to digest labile organic matter and "clean" the plastic surfaces. A final filtering step is used to concentrate the MPs which can then be examined directly on a filter by conventional light microscopy (Masura 2015), stained with Nile Red dye and examined by fluorescence microscopy (Erni-Cassola 2017), or transferred to a spectroscopic window/slide or a suitable filter for chemical imaging by Focal Plane Array (FPA)-?FTIR or Raman spectroscopy (Loder 2015; Tagg 2015; Olesen 2017; Wolff 2019)

An Exploratory Study of Introducing Common Property-Based Management for the Sustainable Groundwater use in Mississippi

Proceedings of the 2019 Mississippi Water Resources Conference

Year: 2019 Authors: Ko J.

Underground water levels have dropped in Mississippi over the last two decades, because most municipalities have depended on groundwater for their tap water sources and irrigations for large-scale cash crop - cotton, corn, soybean farming also have depended on groundwater in the State of Mississippi. The natural resource is regarded as private property and reporting of water use is not required in state. Currently the voluntary reporting of groundwater withdrawal has remained at ten percent and the State of Mississippi is in a legal dispute with Tennessee over the groundwater near the state border to secure more groundwater. These cases show well serious challenges in designing programs for stabilizing water table in aquafer, and for sustainable water use in the State. Elinor Ostrom (co-recipient of the Nobel prize in economics in 2009) and her associates have developed theoretical and empirical studies of common property-based management for natural resources, including aquafer. Western States, which had adopted private property as fundamental right in their state water policies, have increasingly adopted the common property-based management in managing their watersheds and aquafers over the years. For example, Arizona designates the areas experiencing rapidly depleting groundwater as Active Management Areas and mandates estimation of safe-yield and preservation of groundwater for future use. The proposed study examines differences between private property-based and common property-based managements and explores potential changes in Mississippi from the cases of water management in the Western States, if adopted.

Evaluating the Use of sUAS-Derived Imagery for Monitoring Flood Protection Infrastructure

Proceedings of the 2019 Mississippi Water Resources Conference

Year: 2019 Authors: Dietz E., Yarbrough L.D.

In the U.S. there are approximately 33,000 miles of levee. This includes 14,500 miles of levee systems associated with U.S. Army Corps of Engineers programs and approximately 15,000 miles from other states and federal agencies. More than 14 million people live behind levees and associated flood prevention infrastructure. Monitoring and risk assessment are an on-going process, especially during times of flood conditions. The historic events such as those in the City of New Orleans with Hurricane Katrina in 2005, Red River floods of 2009 and 2011, Ohio River flooding of 2018, the 2017 California Floods have profoundly impacted lives and communities. Climate change and increasing population are likely to make flooding events more frequent and costly. As new technologies emerge monitoring and risk assessment can benefit to increase community resiliency.

In this research, we investigate the use of the structure from motion photogrammetric method to monitor positional changes in invariant objects such as levees, specifically, I-walls. This method uses conventional digital images from multiple view locations and angles by either a moving aerial platform or terrestrial photography. Using parallel coded software and accompanying hardware, 3D point clouds, digital surface models, and orthophotos can be created. By providing comparisons of similar processing workflows with a variety of imaging acquisition criteria using commercially available unmanned aerial systems (UAS), we created image sets multiple times of a simulated I-wall at various flight elevations, look angles, and image density (e.g. effective overlap). The comparisons can be used for sensor selection and mission planning to improve the quality of the final product. The results can optimize current equipment capabilities with respect to client expectations and current FAA limitations.

Further Developments of the Hydrodynamic/Water Quality Model for Oyster Restoration in the Western Mississippi Sound

Proceedings of the 2019 Mississippi Water Resources Conference

Year: 2019 Authors: Armandei M., Linhoss A.

The development of a hydrodynamic and water quality model for the Western Mississippi Sound is addressed here. The hydrodynamic part of the model simulates flow, salinity, and temperature. The hydrodynamic part of the model is also the driving mechanism for nutrient transport. The water quality part of the model simulates the physical, chemical, and biological characteristics of Western Mississippi Sound. The model has been developed using the Visual EFDC program that links the hydrodynamic model to the water quality model. A computational grid has been generated consisting of 4 layers, each having 3000 cells. The input data for the hydrodynamic model are; water level, water temperature, salinity, precipitation, solar radiation, wind speed, wind direction, air pressure, and air temperature. The input data for the water quality model are; dissolved oxygen, nutrients (such as Carbon, Nitrogen, Phosphorus and their compounds) and Algae. The simulation time period is from Jan 1st, 2009 to Dec 31st, 2017. The hydrodynamic part of the model is finalized, whereas the water quality part is still being calibrated. The model will be used to identify the most appropriate locations for oyster bed restoration and cultch deployment in the Mississippi Sound.

Groundwater dynamic modeling and sustainable management in Big Sunflower River Watershed

Proceedings of the 46th Mississippi Water Resources Conference

Year: 2017 Authors: Han M., Feng G., Ouyang Y., Gao F.

Groundwater resource in Mississippi Delta is under a serious threat due to overdraft by agricultural pumpage, and showing a decreasing trend since 1970s. Groundwater management strategies are needed for the sustainable development of agriculture in Delta. This study analyzed groundwater dynamics in Big Sunflower River Watershed (BSRW) from 2000 to 2009 using MODFLOW model. The MODFLOW model was set up to quantify the changes in groundwater storage, level, and balance during this simulation period. The model was first calibrated with measured data and compared with the results from previous modeling studies in BSRW with a good agreement. Two scenarios were then chosen to evaluate groundwater management: 1) different crop rotation/sequence, and 2) coupled use of surface water and groundwater for irrigation. The results revealed that the annual change in groundwater storage was highly correlated to the annual amount of precipitation in this region. As the annual precipitation was larger than 60 inch, the groundwater storage increased due to receiving more rainwater recharge and pumping less groundwater for irrigation. Coupling use of surface and ground waters is a sustainable way for water resources management in this region. Appropriate percentages of utilizing groundwater and surface waters were determined under current weather conditions and future climate change scenarios.

Land-use impacts on water quality in Beasley Lake Watershed, Mississippi using AnnAGNPS

Proceedings of the 45th Mississippi Water Resources Conference

Year: 2016 Authors: Yasarer L.M., Bingner R.L., Locke M.A., Lizotte R.

Land-use in agricultural watersheds has a fundamental role in shaping hydrologic processes, erosion, and nutrient export. However, changing land-use can be a challenge when assessing the effects of specific agricultural management practices on overall watershed water quality. On a practical level, this challenge often arises from a lack of data describing field-scale land-use and management practices over time. In this study, detailed land-use and management data from 1995-2009 are utilized to conduct AnnAGNPS watershed simulations for Beasley Lake Watershed located in the Mississippi Delta. AnnAGNPS is capable of estimating field-scale sediment and nutrient export on various spatial and time scales, which allows for spatial and temporal analysis of the effects of land-use change. Two major changes in land-use occurred in the watershed over the study period: 1) a change from predominantly cotton to soybean-rotations in 60% of total watershed cropland, and 2) a change from predominantly cotton to Conservation Reserve Program (CRP) practices in 23% of total watershed cropland. The impacts of these two land-use changes will be examined by comparing nutrient and sediment export at the field-level, as well as overall watershed loads throughout the study period. Results from this study will help understand the effect of overall land-use changes on pollutant loads impacting water quality in the Mississippi Delta, where a general decrease in cotton land-use has occurred from 1999 - 2009, coinciding with an increase in soybean and corn land-use. The information from this study can be helpful to conservationists when developing management plans that incorporate effective conservation practices to improve watershed water quality.

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Analysis of pervious concrete as a stormwater management tool using SWMM Modeling

Proceedings of the 44rd Mississippi Water Resources Conference

Year: 2015 Authors: Abera L.E., Surbeck C.Q.

Stormwater runoff occurs when precipitation flows over the ground. Increase in impervious land cover due to urbanization causes excess stormwater runoff and affects the quantity and quality of receiving water bodies. The use of Low Impact Development (LID) controls is highly recommended to reduce the excess volume of stormwater runoff. LID controls include infiltration techniques such as pervious pavements, evaporation, and storage techniques to reduce the volume of runoff. In this study, performance assessment results of pervious concrete pavement at the University of Mississippi Law School parking area will be presented. The Law School was constructed in 2009 and is adjacent to a privately owned recreational pond. There is a high volume of stormwater runoff from the university area going to the pond, which prompts the university to implement LID tools, such as pervious pavement. Multiple in-place infiltration rate tests, using the ASTM C1701/C1701M-09 standard, were conducted to evaluate the effectiveness of the pervious pavement. Based on the test results, the average infiltration rate of the pervious pavement is 45.14 m/hr, which is less than the desired rate. The U.S. Environmental Protection Agency's Stormwater Management Modeling Tool (SWMM) was used to model the area and to quantify the volume of runoff that can be expected from different intensity storms. Results show that pervious concrete is more effective for a low intensity, long duration storm than for a high intensity, short duration storm.

Monitoring Network Design to Assess Potential Water-Quality Improvements Associated with the Mississippi Coastal Improvement Program in the Mississippi

Proceedings of the 44rd Mississippi Water Resources Conference

Year: 2015 Authors: Rebich R.A., Wilson D.T., Runner M.S.

The Mississippi barrier islands have undergone extensive changes in their formations over the past several decades primarily due to wind erosion and storm surge from hurricanes. In 1969 during Hurricane Camille, a "cut" formed through Ship Island bisecting it into what is known today as East and West Ship Islands. In addition, a tremendous amount of damage and erosion occurred on the two islands and to the shoreline of the Mississippi coast in the aftermath of Hurricane Katrina in 2005. In 2009, the Mississippi Coastal Improvement Program (MSCIP) was enacted by the U.S. Army Corps of Engineers (COE), in conjunction with other Federal and State partners, with the purpose of reducing future storm damage along the Mississippi Gulf Coast. MSCIP includes construction projects along the shoreline of Mississippi as well as major restoration efforts associated with the barrier islands. One such project is to restore Ship Island by filling in the "cut" (also known as "Camille Cut") between East and West Ship Islands thus creating one island again. The restoration effort to close Camille Cut and recreate a singular Ship Island could cause shifts in water quality and aquatic habitat in the vicinity of Ship Island and other areas within the Mississippi Sound. Of particular interest will be the potential increase in turbidity and suspended sediments during the construction phase. Adaptive management planning associated with MSCIP included establishment of a long-term monitoring network design to collect water-quality data to be used as indicators of change for comparison to biological response variables also collected during the study period, and to be used as input for modeling of the Mississippi Sound system to document longer-term change in response to restoration activities in the future. The U.S. Geological Survey (USGS), in cooperation with the COE-Mobile District, has implemented a water-quality monitoring network design in the Mississippi Sound to help achieve programmatic and adaptive management goals of MSCIP. Specifically, two locations near Ship Island have been outfitted to continuously monitor specific conductance (salinity), temperature, dissolved oxygen and turbidity. Nine locations located near Ship Island and near the remaining barrier islands will be visited eight times per year, and during each visit, the same water quality parameters are measured and discrete water quality are collected for nutrient and sediment analysis. This project is a 5-year project to include 1 year of pre-construction, 2 years of construction, and 2 years of post-construction data collection.
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Nutrient Reduction In Mississippi: Partnering For Success

Proceedings of the 43rd Mississippi Water Resources Conference

Year: 2014 Authors: Bhowal P.

Mississippi is blessed with abundant water resources, and protection of these water resources is essential to ensure sustainability of Mississippi's ecosystems and economies. One of the biggest challenges for Mississippi's surface waters, the Mississippi River and the Gulf of Mexico is the presence of excess nutrients in these waters. The Gulf of Mexico contains a hypoxic zone that is a result of nutrient-rich water from the Mississippi River flowing into the Gulf. Nutrients, in the form of nitrogen and phosphorus, come from a variety of sources including farmlands and lawns where fertilizers are used, wastewater treatment facilities, animal wastes from farms and pasturelands. Accordingly, the issues of nutrient pollution and Gulf Hypoxia have become priorities for Mississippi's Delta, Upland and Coastal regions that contribute significant nutrients loading to the Gulf. Mississippi's approach to reduce nutrient loadings within basins and to the Gulf of Mexico is a highly collaborative, stakeholder supported process centered on development and implementation of comprehensive nutrient reduction strategies for the Delta (December 2009), Coastal (March 2011), and Upland (March 2011) regions of the state. These strategies identified 11 strategic elements to help reduce nutrient loading to Mississippi's surface waters. Over 50 staff from multiple state and federal resource agencies and other organizations in Mississippi have been working together to help develop and implement these comprehensive nutrient reduction strategies. Implementation includes engaging stakeholders, characterizing watersheds, determining status and trends, documenting management programs, establishing quantitative targets, selecting analytical tools, identifying/implementing established and innovative best management practices (BMPs), designing monitoring work, providing incentive and funding, and communicating results. These nutrient reduction strategies are currently being implemented in 10 priority watersheds in the Delta (7), Upland (2), and Coastal (1) regions of the state.

Delineation of Watersheds in Northwestern Mississippi to the Sub-Watershed Level

Proceedings of the 43rd Mississippi Water Resources Conference

Year: 2014 Authors: Rose C.E.

In 2009, river systems in Mississippi were delineated to the watershed level, and most were delineated to the subwatershed level. One of the exceptions was the northwestern part of Mississippi in the lower part of the Yazoo River Basin (locally referred to as the "Delta") where only watershed-level delineations were completed. Watersheds and sub-watersheds previously delineated in Mississippi were based on elevation change and water body locations as observed from topographic maps, digital elevation models, and aerial photographs. Previous attempts to delineate watersheds in the Mississippi Delta region to the sub-watershed boundaries were problematic due to the following issues: topographically-uniform, low relief land elevations (less than 100 feet of rise in land-surface elevation from Vicksburg to Memphis); land management practices employed by land owners and growers who frequently change drainage patterns; and insufficient scale of available elevation to allow delineation of subtle topographic features. Therefore, the Mississippi Delta region was not delineated to the sub-watershed level until more precise digital elevation tools were available for use. Delineation of watershed boundaries and designation of watershed numbering and naming is an important first step for resource managers that are concerned with ecosystem and water body health and remediation of point and non-point source pollution. Previous scientific studies have implicated the Delta region as a contributor to the hypoxic zone in the Gulf of Mexico, and a large percentage of Delta waters are listed as impaired on the section 303(d) List of Impaired Waters. For Delta streams, ecosystem health and mitigation of nonpoint source pollution is a primary concern for resource managers, and delineation of watersheds in this region is a critical and necessary step for future planning and mitigation activities. Since the publication of the Mississippi Watershed Boundary Dataset in 2009, the entire Yazoo River Basin (including the Mississippi Delta region) has been mapped using Light Detection and Ranging (LiDAR) technology (funded by the U.S. Army Corps of Engineers, Vicksburg District), which has a root mean square error vertical land surface bare-earth accuracy of 9 centimeters. With the availability of LiDAR data, it is now more reasonable to delineate the Mississippi Delta region to the sub-watershed level. The U.S. Geological Survey, in cooperation with the Mississippi Department of Environmental Quality, has completed the delineation of river systems in the Mississippi Delta region to the subwatershed level.

Crayfish Harvesting: Alternative Opportunities for Landowners Practicing Moist-soil Wetland Management

Proceedings of the 42nd Mississippi Water Resources Conference

Year: 2013 Authors: Alford A.B., Grado S.C., Kaminski R.M.

Harvest of crayfish (Procambarus spp.) for human consumption in the United States and beyond is considerable, amounting to an annual value of $150-170 million annually in the southern United States alone. Most crayfish harvested for human consumption are cultivated in rice fields in southern Louisiana. Management of emergent vegetation in moist-soil wetlands is similar to cultivation of rice where the seasonal wet-dry cycle of these wetlands encourages the growth of annual plants that produce abundant seeds and tubers for waterfowl forage. Recent aquatic invertebrate studies in moist-soil wetlands suggest that populations of crayfish in these habitats may be large enough to warrant a harvest for human consumption. To estimate the economic potential of crayfish harvests in moist-soil wetlands, crayfish yield was estimated from moist-soil wetlands on public and private lands in the MAV in Arkansas, Louisiana, Mississippi, and Missouri in spring-summer 2009-2011 using typical crayfish harvest strategies practiced in commercial rice-crayfish fields of Louisiana. Average daily yields of crayfish from moist-soil wetlands ranged from 0.08 kg/ha to 23 kg/ha with an overall mean yield of 2.73 kg/ha (n = 42, CV = 21%). Whereas the mean daily yield of crayfish from moist-soil wetlands was >3 times less than the yield expected from a high production rice-crayfish culture system (e.g., 8-10 kg/ha), estimated cost associated with harvest of crayfish from moist-soil wetlands were $529/ha and were lower compared to costs associated rice-crayfish harvest practices which were estimated to be $1,856/ha. However, the estimated break-even selling price for crayfish harvested from moist-soil wetlands was $4.90/kg compared to $2.75/kg estimated for rice-crayfish practices. The estimates of break-even selling prices for crayfish harvested from moist-soil wetlands were higher than the 2012 estimate of $2.75/kg price for single crop production of crayfish in Louisiana. However, in areas where crayfish markets are sparse, such as the North Mississippi Delta, landowners may still realize economic potential from this fishery. Harvesting crayfish from moist-soil wetlands may provide a small profit to landowners but will likely provide additional recreational opportunities and can serve as additional extension vehicles to encourage wetlands conservation throughout the MAV.

Assessing and Modeling Sediment Loads from Stream Corridor Erosion along the Town Creek in Mississippi

Proceedings of the 41st Mississippi Water Resources Conference

Year: 2012 Authors: Ramirez-Avila J.J., Langendoen E.J., McAnally W.H., Ortega-Achury S.L., Martin J.L., Bingner R.L.

A research study was developed focused on the identification, assessment, evaluation and prediction of streambank erosion processes within the Town Creek watershed (TCW) in Mississippi. The hypothesis of the study was that streambank erosion is an important mechanism driving sediment supply into the streams and an important portion of the sediment budget for the TCW. A combination of in situ monitoring, geomorphic characterization methods and modeling was performed on different locations along the TCW to quantify the contribution of streambanks to stream sediment loads and better understand the processes of streambank erosion. From the results streambank instability was prevalent and highly erodible materials of streambanks are an important potential source of sediment through the entire watershed. Streambanks predominantly lost materials through gravitational failures and removal of failed sediments by hydraulic forces along the channel headwaters. These geomorphic processes could supply a considerable amount of the estimated 1,000,000 Mg of sediment annually exported from the entire watershed. Headwaters were commonly represented as incised channels near agricultural areas. Annual top streambank retreat occurred up to 2.7 m and contributed annual sediment loads ranged from 0.15 to 28.5 Mg per m-stream. Both assessments were based on repeated measured cross section surveys performed from February 2009 to March 2010. The USDA computational model CONCEPTS (Conservational Channel Evolution and Pollutant transport System) was evaluated on an incised reach of TCW to assess model performance and capability to simulate spatial and temporal changes along the study reach. CONCEPTS accurately predicted the time of occurrence and magnitude of top streambank retreat and failures of streambanks along the modeled reach. Results from field measurements and modeling offered important insights into the relative effects of streambank erosion on the sediment budget for TCW. Reduction of suspended sediment loads should focus on the attenuation of geomorphic processes and stabilization of reaches near agricultural lands at the headwaters within the watershed.

Water quality and other ecosystem services from wetlands managed for waterfowl in Mississippi

Final Project Report

Year: 2012 Authors: Kaminski R.M., Alford A.B.

A successful and increasingly applied conservation practice in the Lower Mississippi Alluvial Valley (MAV) to mitigate loss of wetland wildlife habitat and improve water quality has been development and management of "moist-soil wetlands." This conservation practice has the potential to provide ecosystem services critical to restoring wetland functions in the MAV such as reducing dispersal of sediments and nutrients into surrounding watersheds. Moreover, a significant potential exists for native crayfish (Procambarus spp.) harvest in moist-soil wetlands in the MAV. During spring 2011, we estimated average daily yield of crayfish from 18 moist-soil wetlands in Arkansas, Louisiana, Mississippi, and Missouri. Average daily yield in 2011 was 3.64 kg/ha (CV = 33%). This estimate was slightly greater and more variable than the estimated yield from Mississippi wetlands in 2009 (i.e., 1.75 kg ha^-1; CV = 16%, n = 9) and wetlands in Arkansas, Louisiana, and Mississippi in 2010 (i.e., 2.18 kg ha^-1;CV = 30%, n = 15) . Our estimated daily yield of naturally occurring crayfish from moist-soil wetlands is lower than 10 kg ha^-1 which is the average daily yield from commercially operated rice-crayfish ponds in Louisiana. However, our comparisons of operating budgets from the two harvest systems indicated that rice-crayfish systems incur $1455 in direct expenses per hectare whereas crayfish harvest operation in moist-soil wetlands incur $682 direct expenses per hectare. Although fixed expenses are lower in harvest operations from moist-soil wetlands, lower yields increased the break-even selling prices from $2.75 kg^-1 in rice-crayfish systems to $6.38 kg^-1 in moist-soil harvest systems. These prices, however, are still less than those observed in regions of the Southeastern United States outside of Louisiana. To determine if crayfish harvested from moist-soil wetlands are an acceptable seafood product relative to commercially harvested crayfish, we conducted a consumer acceptability panel in May 2011. We found that crayfish from both sources were well liked and did not differ significantly (p > 0.05) in overall consumer acceptability. In July 2010, we installed water quality monitoring stations at 5 wetlands and 5 agriculture fields. We monitored concentrations of nutrients and sediments exported from these habitats during storm events in December-March of 2010-2012. We determined that wetlands exported significantly less total suspended solids and NO₃ than agriculture fields in 2010-2011 whereas all parameters except for NH₃ were significantly lower in wetland effluent compared to agriculture fields in winter 2011-2012. We were able to calculate loads (kg ha^-1) from wetland habitats during the study years and determined that total annual loads of nutrients were slightly greater than currently assumed loading values of wetlands in Mississippi (i.e., 1 kg ha^-1). Quantifying these ancillary ecosystem services of moist-soil wetlands will encourage further establishment and management of these wetlands in the MAV and elsewhere for wildlife and associated environmental and human benefits.

Develop Hydrological Relationships using a Modeling Approach in Mississippi Delta

Proceedings of the 41st Mississippi Water Resources Conference

Year: 2012 Authors: Jayakody P., Parajuli P.B., Sassenrath G.

Agriculture management practices such as tillage and crop rotations alter the hydrological budget of watersheds. Changes happen to surface runoff can be easily identify with the help of intensive USGS stream gage network, available in Mississippi, but changes to ground water table is less understood as inherent difficulties of measurements. The main objective of this research is to develop relationships among evapotranspiration (ET), soil moisture content (SMC) and depth to the ground water table through modelling approach. The SWAT hydrologic and crop models were setup for the Big Sunflower River watershed (BSRW; 7,660 km²) within Yazoo Rive Basin of the Mississippi Delta. Hydrologic calibration and validation was carried out for the period from 1999-2009 using USGS flow data. Crop model was calibrated and validated for the same period by using Corn and Soybean yield data from the USDA experiment stations. Both crop and hydrologic model performances will be evaluated using coefficient of determination (R²), Nash-Sutcliff Efficiency Index (NSE) and Root Mean Square Error (RMSE). Empirical relationships will be developed to predict depth to the groundwater table using model predicted ET and SMC. The relationships developed will be validated with the field observed data and will be used to make groundwater thematic maps for the Mississippi Delta.

Using Dissolved Oxygen Dynamics to Derive Nutrient Criteria: Tried, True, and Troublesome

Proceedings of the 41st Mississippi Water Resources Conference

Year: 2012 Authors: Hicks M.B., Paul M.J., Caviness K.

Linking nutrient enrichment to adverse ecological effects involves a series of potential causal pathways and proximal stressors. A common proximal stressor is alteration of dissolved oxygen dynamics due to enriched organic matter loading and decomposition. Predictions associated with nutrient enrichment include both the potential for reduced minimum oxygen concentrations, as well as, increased maximum dissolved oxygen and diel fluctuation. Several states have expressed interest in and used oxygen range as a potential response metric. The U.S. Geological Survey sampled more than 50 low gradient Mississippi streams for the period 2009 to present and analyzed samples for dissolved oxygen and nutrients. Several oxygen characteristics were calculated (min, max, range, mean, sd) and related to concurrent nutrient, chlorophyll, and invertebrate assemblage data. All measures of oxygen showed some relation to nutrient concentrations; however, minimum and central tendency measures were most strongly related. At the same time, invertebrate metrics showed a stronger response to minimum concentration among all other measures.
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Ecosystem Services from Moist-Soil Wetland Management

Proceedings of the 40th Annual Mississippi Water Resources Conference

Year: 2010 Authors: Spencer A.B., Kaminski R.M., D'Abramo L.R., Avery J.L., Kroger R.

Moist-soil wetlands in the Mississippi Alluvial Valley (MAV) are dewatered in spring through summer to promote production of grasses, sedges, and other herbaceous vegetation which are prolific producers of seeds and tubers for migrating and wintering waterfowl. Moist-soil wetlands are also potential sites for production and harvest of native crayfish (Procambarus spp.). Harvests of crayfish for human consumption in the United States amounts to $115 million annually. In springs 2009 and 2010, we harvested crayfish from moist-soil wetlands in Arkansas, Louisiana, and Mississippi. We harvested 92.2 kg of crayfish over 1,298 net nights in 2009 and 94.3 kg over 2,005 net nights in 2010. Mean daily harvest of crayfish from moist-soil wetlands was 1.75 kg/ha (CV = 16%, n = 9) in 2009, 1.25 kg/ha (CV = 17%, n = 13) in 2010, and 1.56 (CV = 13%, n = 22) for years combined. Whereas these yields are lower than reported for Louisiana cultured crayfish (i.e., 10 kg/ha), the economic value of native crayfish harvested from moist-soil wetlands may be significant to landowners considering the practice neither requires planting a forage crop for crayfish nor their capture and transport to rice fields. Additionally, within the MAV, strategic location of moist-soil wetlands amid farmed landscapes can reduce dispersal of sediments and other nutrients into surrounding watersheds. In July 2010, we installed water quality monitoring stations at six moist-soil wetlands and six adjacent agriculture fields in the Mississippi portion of the MAV. We will present preliminary estimates and comparisons of concentrations (mg L^-1) and loads (kg) of nitrate, NO_3--N; nitrite, NO_2--N; ammonium, NH4+-N; total phosphorus, TP; total dissolved phosphorus, TDP; particulate phosphorus, PP and; total suspended solids, TSS exported from moist-soil wetlands and agriculture fields. Quantifying these ancillary ecosystem services of moist-soil wetlands will encourage further establishment and management of these wetlands in the MAV and elsewhere for wildlife and associated environmental benefits.

Sustaining Alabama Fishery Resources: A Risk-Based Integrated Environmental, Economic, and Social Resource Management Decision Framework

Proceedings of the 40th Annual Mississippi Water Resources Conference

Year: 2010 Authors: Stovall M.E.

The natural systems that make-up Mobile Bay, its watershed, and adjacent marine waters serve as critical natural infrastructure supporting water supply, transportation, power generation, recreation, commercial fishing, agriculture, forestry, and a wide variety of other valued uses for the people in the watershed. Development activities and multiple uses have placed signification stresses on the ecosystem and the sustainable use of its aquatic resources. These stresses have impacted the unique marine and freshwater biodiversity of this aquatic system.

This paper presents results of Phase 1 of a NOAA funded assessment of the freshwater and marine fisheries of the Mobile Bay watershed, the related aquatic system and the stresses placed on this system by both anthropologic and natural conditions The project is a collaborative effort among government, corporate, and private stakeholders to build the resource management decision support tools needed to assure a sustainable fisheries and coastal seafood industry for Mobile Bay and its watershed, while balancing statewide environmental, economic, and social demands.

Existing system conditions were initially characterized through review of available literature and agency documents. Two collaborative multi-stakeholder workshops were held in 2009 in order to gain their perspective on the most immediate threats to a sustainable Mobile Bay system. Challenges associated with multi-stakeholder coordination, resource allocation among potentially competing uses, and public education of how human activities potentially impact system health were ranked as higher threats for sustainable system management than more traditional environmental perturbations such as non-point source pollution or aging infrastructure.

Results from Phase 1 studies have identified tentative indicator species, sources of stresses, model boundary conditions and other major system components for Phase 2 activities to develop a preliminary decision support system, which will link riparian, stream, estuary, and near-shore marine conditions responses to various human use activities via selected indicator species monitoring. The long-term project outcome is to design and develop new tools to model and evaluate social and environmental factors that influence management of a sustainable fishery, support man-made infrastructure investment decisions, and provide a common language for expressing goals, processes, and concerns affecting responsible stewardship of Alabama’s fisheries resources.

Recent developments incorporating decision impacts of near-shore drilling will also be discussed.

Water quality and other ecosystem services from wetlands managed for waterfowl in Mississippi

Final Project Report, Project 2009MS86B

Year: 2010 Authors: Kaminski R.M., Spencer A.B.

A successful and increasingly applied conservation practice in the Lower Mississippi Alluvial Valley (MAV) to mitigate loss of wetland wildlife habitat and improve water quality has been development and management of "moist-soil wetlands." Whereas a primary goal of moist-soil management is to provide abundant food resources for waterfowl and other waterbirds in the MAV and elsewhere on the wintering and migrational grounds, this conservation practice has the potential to provide ecosystem services critical to restoring ecosystem functions in the MAV. Within the MAV, strategic location of natural moist-soil wetlands amid farmed lands can reduce dispersal of sediments and other nutrients into surrounding watersheds. Moreover, a significant potential exists for native crayfish (Procambarus spp.) harvest in moist-soil wetlands in the MAV. Our current research is designed to quantify nutrient management and crayfish harvest as ecosystem services provided by moist-soil wetland management in the MAV. During spring 2009, we estimated baseline water quality parameters and average daily yield of crayfish from 9 moist-soil wetlands in Mississippi. Mean NO₃-N, NH₄-N, and PO₄-P concentrations were variable whereas total suspended solid concentrations decreased over time. Average daily yield of crayfish was 1.75 kg ha^-1 (CV = 16%, n = 9). We continued our study in spring-summer 2010 in wetlands in Arkansas, Louisiana, and Mississippi. Preliminary estimates of average daily yield of crayfish in 2010 was 2.18 kg ha^-1 (CV = 30%, n = 15). In July 2010, we installed water quality monitoring stations at 6 wetlands and 6 agriculture fields. We will use the data from these stations to estimate and compare monthly loads (kg ha^-1) of nutrients and solids from moist-soil wetlands and flooded agricultural fields. Quantifying these ancillary ecosystem services of moist-soil wetlands will encourage further establishment and management of these wetlands in the MAV and elsewhere for wildlife and associated environmental benefits.

Water Supply in the Mississippi Delta: What the Model Has to Say

Proceedings of the 40th Annual Mississippi Water Resources Conference

Year: 2010 Authors: Mason P.

A regional groundwater flow model has been built as a tool to better understand the system flows and to project future water levels in the Missisippi River Valley alluvial aquifer (MRVA). This is a highly productive aquifer which supports vast amounts of agriculture and aquaculture in northwest Mississippi. Water levels are declining in this aquifer and will be of increasing concern in the future.

To quantify discharge, the model incorporates a method of estimating pumpage for agriculture and aquaculture, based on crop distribution patterns and rainfall-response factors.

Recharge to the aquifer is complex and unusual, since a widespread impermeable surficial unit restricts rainfall infiltration in most of the Delta plain. Good calibration was achieved only when the model fully accounted for recharge data from several sources. Positive recharge sources are: groundwater in the adjoining formations on the eastern bluff hills line, rain infiltration through the alluvial fans along the bluffline, and rain infiltration through sandy areas along the Mississippi River.

Other sources serve as both discharge and recharge areas for the aquifer, depending on season and/or location. These are: the Mississippi River, the underlying Tertiary aquifers (Cockfield and Sparta), the major rivers and the bluffline streams.

The base model period, built from known data for streams, precipitation, crops, and water levels, etc. ran 1996 through 2006. On average, the aquifer lost about 230,000 acre-ft of water per year from 1996 to 2006. During this time, pumpage per season averaged about 3 million acre-feet, with a minimum of 1.7 million acre-feet in 2002 and a maximum of 4.5 million acre-feet in 2000. Rainfall infiltration averaged about 2.4 million acre-feet per water-year, with a low of 1.9 million acre-feet in 1998 to a high of 3 million acre-feet in 2003. Over the ten year period, there were 2 years during which rainfall infiltration exceeded pumpage. In 8 of the years pumpage exceeded rainfall infiltration.

Several scenarios have been run from 2009 water levels forward, simulating conditions 20 years into the future, and the results of these are presented.

Plan for Monitoring Success of Mississippi’s Delta Nutrient Reduction Strategy

Proceedings of the 40th Annual Mississippi Water Resources Conference

Year: 2010 Authors: Hicks M., Stocks S., Wright J.

A multi-agency task force forum, The State Nutrient Strategy Work Group, was formed in 2009 for the purpose of developing a consistent approach among Mississippi/Atchafalaya River Basin states to reduce nutrient loadings from streams and rivers draining into the Gulf of Mexico. As part of this forum, a nutrient reduction strategy for the Delta region in northwestern Mississippi was developed. One of twelve critical elements identified in the nutrient reduction strategy was to implement "Monitoring Programs" for the purpose of documenting nutrient concentration and load reductions, lag times, and watershed system responses. To address this element, two project areas were identified: Harris Bayou watershed, Coahoma County, MS, and Porter Bayou watershed, Sunflower County, MS. Project areas were chosen based on areas where there has been historically high nutrient concentrations and where land-owners are willing to participate in this effort. These two watersheds are also located in a focus area watershed of the Mississippi River Basin Initiative. Efforts have begun to implement various Best Management Practices (BMPs) in four catchments, two in each of Harris and Porter Bayous, for the purpose of improving water quality by reducing nutrient loading to streams affecting downstream aquatic ecosystems. In 2010, the U.S. Geological Survey, in cooperation with Mississippi Department of Environmental Quality, U.S. Army Corps of Engineers, and Delta Farmers Advocating Resource Management (F.A.R.M.) began implementation of a monitoring strategy at two stations in Porter Bayou watershed and four stations in Harris Bayou watershed. The strategy involves monitoring before and after BMPs have been implemented, as well as using a paired basin approach for data analysis of changes due to the BMP project. Data collection activities at each site include base and storm flow sampling for flow, total nitrogen and other nitrogen species, total phosphorus, suspended sediment, and other physical and chemical water quality indicators of ecosystem health, including response indicators such as benthic macroinvertebrate community assemblages and chlorophyll-a concentrations.

The Future of K-12 Water Education: The 2010 Mississippi Framework and the Proposed National Research Council Framework for Science Education

Proceedings of the 40th Annual Mississippi Water Resources Conference

Year: 2010 Authors: Clary R.M., Brzuszek R.F., Wandersee J.H.

Previous researchers (Brzuszek et al 2009) investigated the role of non-governmental organizations (NGOs) in four northern Gulf Coast watersheds (Alabama, Florida, Louisiana, and Mississippi), and reported that the NGOs’ focus varied by watershed. However, subsequent analysis of these northern Gulf States’ educational standards revealed that the NGOs’ focus was not being reflected in the respective state’s water education requirements (Clary & Brzuszek 2009). Under the 2001 Mississippi Science Framework, 69% of the researchers’ 13 identified water topics were included, but most of these were non-required objectives, or within elective courses that are not taught at all Mississippi schools. Only one topic, pollution, was required to be taught as a state competency (grade 4). While Louisiana fared better than other coastal states with 54% of the water content topics in K-12 education, several topics were still omitted. Clary and Brzuszek (2009) concluded that greater collaboration was needed between watersheds, their associated NGOs, and educators to implement water education in public schools through the required science content standards.

However, science education is not static: Both the 2010-11 adoption of Mississippi’s 2010 Science Framework and the recently released 2010 National Research Council (NRC) draft of the conceptual Framework for Science Education indicate that new challenges and opportunities exist for water education. Our current research compared water education topics in the Mississippi 2010 Science Framework against the earlier 2001 Framework. While there is greater vertical alignment between grades K-8 in the 2010 Framework, many of the water topics are included as optional objectives and not as required competencies, resulting in increased water education possibilities with teacher flexibility. Content analysis of the preliminary public draft of the NRC science framework also revealed flexibility and water education potential: Although water education was not regularly mentioned in the document, the new NRC draft focuses upon "learning progression." Another notable change is the incorporation of Engineering and Technology as a fourth domain of science alongside the current domains (Life, Earth and Space, and Physical sciences).

Both Mississippi ’s vertical alignment and the NRC learning progressions are consistent with our best practices model (Clary & Brzuszek 2009). These documents also suggest a potential educational trend toward increased content reinforcement across grade levels and teacher flexibility. We suggest there may be increased opportunity for NGOs to develop water education programs at multiple grade levels that address these broader science standards, resulting in greater inclusion of water education within the local watershed.

Three-dimensional Heterogeneity of Hypoxic Water Masses in the Mississippi Sound: The Geomorphology Connection

Proceedings of the 40th Annual Mississippi Water Resources Conference

Year: 2010 Authors: Milroy S.P., Moshogianis A.

Seasonal hypoxia is certainly common over the Louisiana-Texas (LATEX) shelf west of the Balize Delta, but over the last several years summer hypoxia has also been discovered east of the delta in the Mississippi Bight (Dillon et al. 2008, Brunner et al. 2009) and in the deeper reaches of the Mississippi Sound (Gundersen, pers. comm.). Hypoxia most commonly occurs during times of significant vertical stratification of the water column, caused by the complimentary effects of seasonal heating and freshwater discharge. These discharges, when laden with organic and inorganic nutrients, further exacerbate the geographic extent of these hypoxic water masses. While the causative agents of coastal hypoxia have been well-described, the synergies between coastal geomorphology and the net ecological burden (O₂ production v. respiration) within the Mississippi Sound/Bight are less well-known. Over a series of cruises conducted from 01 APR–30 JUL 2010, vertical profiles from thirty repeat stations within a highly resolved (25 km²) grid were analyzed monthly for in situ CDOM/phycoerythrin/chl-a fluorescence, temperature, salinity, and dissolved oxygen. Results indicate that differences between surface and near-bottom chl-a, coupled with the unique geomorphology of the Mississippi Sound/Bight, can produce hypoxic water masses with significant heterogeneity over fine spatial scales.

Use and Effectiveness of Natural Remediation of Wetlands at the GV Sonny Montgomery Multi-Purpose Range Complex-Heavy (MPRC-H), Camp Shelby Joint Forc

Proceedings of the 40th Annual Mississippi Water Resources Conference

Year: 2010 Authors: Floyd I.E., Orsi T.H.

The GV Sonny Montgomery Multi-Purpose Range Complex-Heavy (MPRC-H) is a training range, located within the Camp Shelby Joint Forces Training Center (CSJFTC), MS, and is used by armored and mechanized infantry and attack helicopter units. Construction of the range occurred in 2004 during a period of low regional precipitation. Lack or inadequate installation of sediment control structures (sediment fences and matting), combined with high daily rainfall over a 2 week period, led to extensive erosion within and around the range and sediment infilling of two parts of Davis Creek basin, immediately outside the MPRC-H. The impacted areas covered over 42 wetland acres and were infill with sediment 6-14 inches thick. Thereafter, proper erosion control structures were installed and natural remediation was selected as the most viable option for site regeneration.

The impacted areas outside the MPRC-H have been monitored since 2005, most recently in 2009. During the 2005 assessment, the absence of small vegetation was most obvious and the event lead to dramatic increases in turbidity within the Davis Creek tributary and subsequent downstream tributaries. Interestingly, elevated turbidity levels were noted for almost 2 years after the sediment control structures had been repaired and/or replaced. During our 2009 survey, it was determined that fluvial, overland runoff processes and infill compaction within the MPRC-H wetland have led to substantial reductions in the aerial extent (39%) and thickness (30%) of the sediment plume. None-the-less, even with this significant removal of material, the remainder may or may not be removed by natural processes over timescales of human and engineering interest. However, understanding the processes that have taken place in and around the MPRC-H should form a template for future sites to determine which remediation option, anthropogenic or natural, is most cost-effective and beneficial.

Headwater Hydrologic Functions in the Upper Gulf Coastal Plain of Mississippi

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Choi B., Ezell A.W., Dewey J.C.

Headwater streams are often considered to be contributors of nonpoint source sediment in forested watershed areas and are a key component of overall hydrologic processes because they comprise more than 60-80% of stream networks and watershed land areas. However, the relationship between silvicultural practices in the uppermost portions of headwater systems characterized by ephemeral-flow areas and their downstream linkages is poorly understood. In Mississippi’s forestry best management practices (BMPs) manual, streamside management zones (SMZs) have specific guidelines for perennial and intermittent streams, but ephemeral streams are rarely considered in forest resources management. This study is being conducted in Webster County, Mississippi to (1) examine the influence of ephemeral-flow portions of headwaters on downstream hydrology and water quality, and (2) evaluate silvicultural BMPs effectiveness of ephemeral streams in protecting downstream water quality. Specific objectives of this study are to test effects of four levels of harvest in ephemeral-flow areas on (1) in-stream water quality and total suspended sediment (TSS), (2) surface erosion and deposition in pre- and post-harvest conditions, and (3) the responses in subsurface hydrology. This study is installed as a randomized complete block (RCB) design consisting of three replicates of four treatment watersheds (No BMP, BMP1, BMP2, No harvest) representing a range of potential BMPs for ephemeral-flow portions of headwater streams. Results consisting of one year of pre-treatment data and two years of post treatment data will be presented. This study will increase our understanding of effectiveness of the headwater BMPs in mitigating timber harvesting impacts on water quality in riparian areas as well as providing information on the relationship between hydrological connections between perennial and ephemeral streams, and overall water quality.

Recharge in the Water Budget of the Delta’s Alluvial Aquifer

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Mason P.

The Missisippi River Valley Alluvial Aquifer (MRVA) is a highly productive aquifer which supports vast amounts of Delta agriculture and commerce. Maintaining an adequate future water supply requires understanding of the water budget. Stated simply: current water levels + recharge - discharge = future water levels. Focusing on the recharge term in the equation, existing evidence about recharge to the MRVA is reviewed, and current active research is described.

Normal direct recharge by precipitation is extremely restricted in the MRVA because of a widespread impermeable unit just below the soil profile. Direct recharge is, however, active in localized areas, particularly through the conduit of the alluvial fans along the eastern boundary of the Delta plain. An estimated 220 square miles of land surface is covered by fans, with vertical relief ranging from 4 to 66 feet. Drilling reveals much greater thicknesses of alluvial fan deposits occur below the surface, coeval with deposition of the MRVA.

Recharge from streams is also a significant factor in the bluff margin area, where streams cross fan sediments which lie in connection with the MRVA. In summer, many smaller streams can be observed to lose flow and disappear as they traverse fans. Direct discharge measurements of larger streams have recorded every condition as streams cross the fans, from gains on clay dominated fans, to significant losses over sandy materials, suggesting that the variable source geology of the reworked sediment making up each fan tends to control the amount of gain or loss of flow from any given stream to the aquifer.

Efforts are underway to characterize and quantify water heads and pathways along the Bluff Hills boundary for use in a large flow model. These include data collection regarding the size and hydraulic conductivity of the alluvial fans, the role of Yazoo headwater streams and other surface watersheds, and the involvement of the several geologic formations adjacent to the MRVA.

Water Quality Assessment in the Town Creek Watershed, Mississippi

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Ortega-Achury S.L., Ramirez-Avila J.J., McAnally W.H., Martin J.L.

Surface water quality is deteriorating around the world at an increasingly alarming pace. The majority of the incidences from nutrient impacts are primarily occurring in areas with increased development. Town Creek Watershed is located within the Tombigbee River Basin representing 50% of the Upper Basin and is approximately 10% of the entire Tennessee-Tombigbee Waterway Watershed. Town Creek watershed directly contributes to the Aberdeen pool on the Tennessee-Tombigbee Waterway. Data relating sediment and nutrients concentrations and discharges after 1994 are not available for most of the watersheds within the Tombigbee River Basin. The objective of this study is to provide valuable water quality data for the upper Tombigbee Watershed. The study area included four of the five sub-basins within Town Creek that according to the EPA and MDEQ are biologically impaired due to sediment and nutrients. The study monitored the water quality conditions in the major tributaries of Town Creek Watershed. Grab samples and in situ measurements of water quality parameters (dissolved oxygen (DO), temperature (T), electric conductivity (EC), turbidity, and pH were taken at 24 stations with 7 along the principal channel within the study area. The collected water samples were analyzed for total phosphorus (TP), dissolved reactive phosphorus (DP), and suspended sediment concentration (SSC). Preliminary results for the monitoring period of May 2008 to February 2009 showed mean values for T, pH and EC of 23 °C, 8, and 343 mS cm^-1, respectively. DO concentrations and turbidity levels showed mean values of 6.4 ppm and 14 NTU, respectively. Phosphorus and sediment concentrations presented mean values of 0.07 mg L^-1, 0.12 mg L^-1, and 19 mg L^-1 for DP, TP and SSC, respectively. Significant levels of impairment on water quality were observed at sampling stations surrounding and receiving water from the urban area (City of Tupelo and Plantersville plants of water treatment). The most important source of SSC was the area under construction for the Toyota Assembly Plant at Blue Springs, MS. Tributaries downstream of the Town Creek at the Brewer Rd site were not important contributors of sediments and P; however, they do contribute a significant volume of flow allowing for a dilution effect that kept constant the mean SSC. Considering the 0.1 mg-TP L^-1 water quality criteria, the headwater areas were not impaired by P concentrations, while the tributaries near and after the urban areas presented P impairment showing mean concentrations values up to 1.2 mg-TP L^-1.

Treatment of Timtek Process Water by Co-Composting

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Mangum L., Borazjani H., Seale R.D., Diehl S.V., Prewitt M.L., Sloan C.

The Timtek process involves crushing of small diameter trees to form mats which are coated with adhesive then pressed into boards. The crushing process yields effluent water that has a high biological oxygen demand (BOD), chemical oxygen demand (COD), and total suspended solids (TSS). This water must be remediated before it can be discharged into public water systems. A six month study was conducted to evaluate the effectiveness of co-composting of the process water with wood waste and chicken manure as a method of remediation. Wood waste from the pilot facility in Shuqualak, MS was ground into sawdust. This sawdust was composted using four treatments with deionized water or process water to adjust moisture content. Two treatments were amended with manure to provide a nitrogen source; two received only deionized water or process water. The compost end-products for all treatments were then evaluated for relative toxicity, weight loss, maturity and suitability as a container substrate in a greenhouse experiment using pansies. Additional testing was conducted to determine the toxicity of compost leachate and to evaluate the effects on germination rates of sensitive plant species. Co-composting successfully reduced the bulk and toxicity for all treatments. Treatments containing manure and process water showed over 90% emergence rate of radish seeds by day 90. The manure amendments were also comparable to the commercial greenhouse substrate in aiding plant biomass production. The end result of the experiment was the production of a bio-based value added medium that was non-toxic and suitable for soil amendment/potting mix.

Support for a Northeast Mississippi Regional Water Management Plan

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Tagert M.L.

Water and wastewater infrastructure are national priority issues for economic development, pubic health and environmental concerns. Currently, in predominantly rural states such as Mississippi, water supply infrastructure is operated and maintained largely by many independent small public water systems. Similarly, rural wastewater infrastructure is essentially nonexistent. As new development projects have recently been announced in Northeast Mississippi, regional water and wastewater organizations are critical for Northeast Mississippi Counties to plan, build, operate and maintain the necessary infrastructure to ensure an adequate water supply for the future and adopt a viable rate schedule to be self-sufficient. Recognizing this situation, the Tombigbee River Valley Water Management District (TRVWMD) is formally creating two new multi-county water and sewer organizations within their twelve member Counties. The ‘Tri-County District’ covers Itawamba, Prentiss, and Tishomingo Counties, while the ‘Five-County District’ covers Chickasaw, Clay, Kemper, Lowndes, and Noxubee Counties. All participating Counties have passed resolutions to establish a new Water and Sewer District, and the TRVWMD sought Mississippi State University’s assistance in completing a Water Management Plan for the Tri-County District, which is a requirement of the formal permitting process to establish a new District. This presentation will address the planning process and elements of the Tri-County Water Management Plan, which has a primary emphasis on water supply and contains contributions from various Northeast Mississippi stakeholders such as local, state, federal, and regional agencies and organizations.

Urban Stormwater Runoff Phosphorus Loading and BMP Treatment Capabilities

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Perry S., Garbon J., Lee B.

Continued land development through urbanization is deteriorating surface water quality. A significant concern with our limited global fresh water resources is the onset of toxic algae blooms and reduced dissolved oxygen due to continued, uncontrolled phosphorus loading from an ever increasing source, urban development. This is leading to negative ecologic, economic, and human health impacts. As a result, regulators are beginning to acknowledge the impairment of fresh water bodies, and have begun implementation of Total Maximum Daily Loads (TMDLs). However, applying phosphorus related TMDLs specifically to urban stormwater runoff may not be effective without first understanding the available mechanisms and limitations involved in phosphorus treatment for stormwater applications.

To achieve high levels of permanent phosphorus removal, review of the fate and transport of Phosphorus, including both particulate-bound and dissolved phosphorus, in urban stormwater runoff is necessary. Significant field monitoring data of various stormwater Best Management Practices (BMPs) exists which illustrates advantages and disadvantages of removal mechanisms, and ranges of performance variance in both conventional Best Management Practices (BMPs) as well as newer Low Impact Development (LID) applications.

Advances in phosphorus treatment technologies have recently become available and better understood, providing the ability to capture high levels of both particulate-bound and dissolved phosphorus. Amending both conventional BMPs and LID applications with engineered solutions offers increased ability to achieve existing and future phosphorus based TMDLs. These concepts, performance data and design amendments are discussed as a potential means to protect our fresh water resources from remaining eutrophication.

Sediment Budget Analysis for Town Creek Watershed, MS

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Ramirez-Avila J.J., Sharp J., McAnally W.H., Ortega-Achury S.L.

The Town Creek watershed is located in the Northeast area of Mississippi. It covers 1,769 km² and represents approximately 50% of the upper Tombigbee River basin area contributing to the Aberdeen Pool on the Tennessee-Tombigbee Waterway. The sediment yield from the watershed attributes to the estimated 320,000 ton/yr of deposition in Aberdeen pool, where annual dredging averages 310,000 ton/yr. To produce remedial measures for reducing water quality impairment, and dredging costs (expressed in terms of a percent reduction of sediment loads), and future BMP’s in Town Creek watershed, it is necessary to know the sediment sources and loads currently transported within the watershed. A sediment budget for a partial sub-basin within Town Creek watershed is investigated by means of experimental and modeling methods, including HEC-RAS and the Sediment Impact Analysis Method (SIAM). SIAM is a rapid assessment screening tool used to evaluate the impacts of sediment management activities and determine trends in sedimentation. The tool is incorporated in the latest version of the U.S. Army Corps of Engineers HEC-RAS model as a design module. Local sediment sources/sinks (e.g. tributary inputs, landuse practices) as well as the upstream and downstream boundary conditions are defined by using computational tools, field surveys, and sediment sampling. The analysis performed is expected to provide a general assessment of the sediment budget components within a representative watershed within the Tombigbee River Basin.

Interaction of the Mississippi River with the Mississippi River Valley Aquifer in Northwestern Mississippi

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Bordonne O., Barlow J.R., Coupe R.H.

The Mississippi River Valley Alluvial Aquifer (MRVA) in northwestern Mississippi is in direct connection with the Mississippi River, discharging into the River at times of base flow and being recharged by the Mississippi River at times of high flow. Modeling studies have indicated that over the long term, there is a net zero exchange of water between the Mississippi River and the MRVA. However, because of increased groundwater withdrawals for agriculture over the past few decades, groundwater levels have been declining in the MRVA; this decline has likely changed the interaction between the Mississippi River and the MRVA. Changes in surface- and groundwater interactions are important to understand, especially as local agencies attempt to implement policies to use the MRVA in a sustainable manner. In order to quantify the exchange between the Mississippi River and the alluvial aquifer, continuous data collected over the last decade from wells located near the Mississippi River were used to identify recharge and discharge periods and to estimate the net balance between the river and aquifer. Historical water-level data were also used to determine if the relation has changed over time.

The Effects of Land Use on Streams Along the Natchez Trace Parkway Using Rapid Bioassessment Protocols

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Earleywine B., Dibble E.

Stream quality is commonly assessed using the Environmental Protection Agency’s rapid bioassessment protocols for the habitat, fishes, and benthic macroinvertebrates. These assessments are useful to evaluate impacts that land use may have on streams. We conducted bioassessments in eighteen streams, identified land uses, and compared water quality parameters of forty-four streams along the Natchez Trace Parkway. We measured for potential land use effects by sampling water quality metrics (April 2008-February 2009), benthic macroinvertebrate and habitat assessment protocols (June 2008), and fish protocols (February 2009) to demonstrate differences across six subregional watersheds. The three dominant land uses were deciduous forest, pasture/hay, and evergreen forest respectively. Deciduous forest was most abundant in the Upper Cumberland, Lower Cumberland, and Tennessee watersheds while evergreen forest covered more area in the Mississippi, Pearl, and Tombigbee watersheds. Habitat assessment scores averaged highest in the deciduous forest-dominant watersheds and lowest in the blackwater stream watersheds dominated by evergreen forests. The Pearl watershed, comprised mostly of evergreen forest land, had the lowest average dissolved oxygen, alkalinity, conductivity, pH, and nitrate. Turbidity and total suspended solids decreased as latitude increased. Fecal E.coli colony estimates were highest in Mississippi and Upper Cumberland watersheds. Latitudinal differences were also observed in the macroinvertebrate assemblages. Tennessee, Lower Cumberland, and Upper Cumberland watersheds had more shredders and were the only watersheds with Plecoptera. Relationships between fish and macroinvertebrate integrities are discussed for each stream and watershed.

Turbidity as a Surrogate for the Estimation of Suspended-Sediment Concentrations in Mississippi Streams

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Runner M.S., Stocks S.J.

The U.S. Geological Survey currently collects suspended-sediment concentration data at more than 25 hydrologic monitoring stations in Mississippi. Data are collected to describe suspended-sediment concentrations and loads over the range in discharge for these stations and to determine if trends in the sediment-discharge relation exist, as well as describe changes in those trends. Where sufficient data are collected, they can be used to compute the load of sediment transported in suspension during storm events.

Traditional methods for obtaining suspended-sediment concentration data require the collection of water samples that are shipped to a laboratory for analysis. Depending on a variety of factors, it can take up to 6 months from the time of sample collection to receipt of laboratory results. To expedite the availability of these data to the cooperators, which will allow decisions to be made in a timely manner, the U.S. Geological Survey began a study to develop a method to estimate suspended-sediment concentrations using a surrogate. The method is based on the success of previous studies, which indicated that for streams with certain hydrologic and sediment characteristics, site-specific relations between turbidity and suspended-sediment concentrations could be developed, which allow the estimation of the sediment concentration.

For this study, turbidity data are being collected by using two methods. First, in situ water-quality monitors are installed at two continuous-record stations where discrete suspended-sediment concentration data are collected. Turbidity data are collected on a regular time interval, generally every 15 minutes, by water-quality monitors deployed in the water at these stations. The measured turbidity values are compared with the suspended-sediment concentrations in water samples collected by using automatic pumping samplers. Second, water samples collected at locations without continuous water-quality monitors are analyzed for turbidity by using a bench-top turbidity meter prior to the samples’ shipment for analysis. Water samples collected at stations with continuous water-quality monitoring are also analyzed using the bench-top meter so that comparisons can be made between the two methods.

Preliminary results indicate that reasonable turbidity-sediment relations can be developed for many of the stations that are currently being tested as part of this program. These relations could provide a means to estimate suspended-sediment concentration for water samples collected by automatic pumping samplers, as well as provide a means to reduce the costs associated with collecting data necessary for the evaluation of environmental projects.

Mississippi River Bluff Line Streams

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Starnes J.E.

A multitude of deeply incised, distinctive streams drain the Mississippi Loess Bluffs from Memphis southward to Natchez. These hydrologic features (and supported biota) are strongly influenced and controlled by complex Quaternary and Tertiary lithologic layers. These "bluff line streams" support unique, complex, and delicate sets of aquatic ecosystems, some of which are considered to be ice-age relics. Locally, these dendritic systems support the recharge of the Mississippi River Alluvial Aquifer (MARVA) as their trunk streams enter into the Mississippi River Alluvial Plain across copious, low relief, alluvial fans. These streams are threatened by in-stream mining, oil and gas production activities (shallow salt water injection, evaporation pits, and spills), industrial and housing development, deforestation, nonpoint source pollution such as agricultural runoff, solid waste dumping, and stream-bed alteration. Such activities can have profound negative impacts; degrading water quality, threatening aquatic/terrestrial biology, amplified erosion, localized excessive sedimentation, and spoiling sensitive, natural eco-system balances. Heightened awareness, study, and understanding of integrated and interdependent processes (geology, hydrology, biology) is essential to maintaining and sustaining delicate, unique, bluff line stream environments.

Fish and Invertebrate Assemblage Relations to Dissolved Oxygen at 35 Sites in Southern Louisiana

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Justus B.G., Wallace J.E.

From 2005 to 2007, the U.S. Geological Survey sampled fish and invertebrate assemblages and monitored dissolved oxygen during critical summer conditions at 35 stream sites in southern Louisiana. The purpose of the study was to assess relations between fish and invertebrate assemblages and dissolved oxygen, and to provide information that could be used to validate or refine existing aquatic life use categories and dissolved-oxygen criteria (5 milligrams per liter) for streams in southern Louisiana. Sites with a range of ecological conditions were selected for sampling by the U.S. Environmental Protection Agency Region VI, and nine sites were considered to be least impaired. Dissolved-oxygen concentrations were standardized to 0800, a time when concentrations were near the daily minimum, and were compared to approximately 370 biological metrics. Piecewise regression was used to evaluate biological metrics for break points to indicate a minimum (biological) threshold concentration for dissolved oxygen. Preliminary data indicate a biological threshold exists between 2 and 3 milligrams per liter of dissolved oxygen. This finding indicates that fish and invertebrate assemblages in low-gradient streams have adaptations that enable them to withstand low dissolved-oxygen concentrations.

Water Quality Monitoring Plan and Implementation, Lake Washington Mississippi, 2008

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Hicks M.B., Stocks S.J.

Lake Washington is located in Washington County in northwestern Mississippi, and drains into Washington Bayou, a tributary of Steele Bayou. The lake is an oxbow formed by an abandoned meander of the Mississippi River. About half of the land use in the watershed is agriculture: major crops are cotton, corn, soybeans, wheat, and rice. Although the watershed is relatively rural, housing development has increased near the lake since 2003. Water quality in Lake Washington has gradually declined during the last 30 years. In 1991, results of a study by the Mississippi Department of Environmental Quality (MDEQ) indicated that nutrient enrichment was affecting Lake Washington as a result of high phosphorus and nitrogen concentrations in the lake. In that same year, a watershed restoration project was initiated by MDEQ to demonstrate and assess best management practices to reduce sediment and nutrient concentrations in Lake Washington. Results of a follow-up study by MDEQ in 1996 indicated that nutrient enrichment in Lake Washington was continuing due to continued high phosphorus and nitrogen concentrations in the lake.

A group of State and Federal agencies and local organizations, known as the Yazoo Basin Team and part of the Basin Management Approach of MDEQ, identified Lake Washington as a priority area for watershed restoration, and as a result, the Lake Washington Watershed Implementation Team was formed in 2005. The team developed a Watershed Implementation Plan in 2007 with the goal of improving water quality of Lake Washington, in which reduction of sediment and nutrient loads were considered high priorities. The plan calls for reduction of sediment loading by 55 percent and associated organic matter loading by about 50 percent through implementation and maintenance of various best management practices. In coordination with water-quality improvement efforts outlined in the Watershed Implementation Plan, water-quality data are being collected to document suspended-sediment and nutrient characteristics of Lake Washington and loads in runoff entering Lake Washington before, during, and after implementation of efforts outlined in the plan. Nutrient concentrations (nitrogen and phosphorus), suspended sediment concentrations, and flow at two major inflows of Lake Washington are being monitored by the U.S. Geological Survey, and MDEQ personnel are collecting nutrients and chlorophyll-a data at two main lake sites. In addition, multi-parameter water-quality sondes will be deployed by USGS at two sites near the two MDEQ main lake sites, at a single depth (approximate of the middle of photic zone) to collect hourly readings of water temperature, specific conductance, dissolved oxygen, pH, and turbidity.

Water-Quality Data of Selected Streams in the Mississippi River Alluvial Plain, Northwestern Mississippi, September–October 2007-08

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Hicks M.B., Stocks S.J.

Between September 2007 and October 2008, the U.S. Geological Survey, in cooperation with the U.S. Environmental Protection Agency and the Mississippi Department of Environmental Quality, collected and analyzed water-quality samples from streams in the Yazoo River basin within the Mississippi River Alluvial Plain in northwestern Mississippi. Water-quality samples were collected and analyzed for various physical and chemical characteristics, including but not limited to suspended sediment, nutrients, and chlorophyll a. In addition, continuous field parameter measurements (water temperature, pH, specific conductance, dissolved oxygen and turbidity) were collected at 30-minute intervals for a minimum of 72 hours using deployed multi-parameter water-quality sondes. In 2007, water-quality samples were analyzed from 56 sites located across the study area with continuous data measured at 28 of these sites. In 2008, water-quality samples were analyzed and continuous data measured at an additional 16 sites across the study area. Data collected throughout this project will be used in the development of water-quality indicators to assess water-quality health. These indicators will assist in the development and evaluation of restoration and remediation plans for water bodies not meeting their designated uses, as stated in the U.S. Environmental Protection Agency’s Clean Water Act Section 303(d).

Beneficial Use of Marginal Quality Water

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Kellogg W.

The Mississippi Alluvial Aquifer is the most heavily used aquifer in the state of Mississippi. Extensive use of the aquifer has overdrawn the aquifer in some areas and caused large cones-of-depression making continued pumping at the current rate unsustainable. The alluvial aquifer overlies deeper aquifers of the Mississippi Embayment Aquifer system. The alluvial aquifer can be as much as 250 feet thick and the Mississippi Embayment Aquifer system can be as much as 6,000 feet in thickness. Water usage is approximately 2 billion gal/day from the alluvial aquifer and 433 million gal/day from the deeper Mississippi Embayment Aquifers.

Many of the deeper aquifers contain fresh water (<500 mg/l TDS) in the northern part of the Mississippi Embayment, but TDS concentrations increase in the southern portion of the Embayment making the water unsuitable as a potable water supply without treatment. Many industries use fresh water supplies when they could be using brackish water (TDS 1,000 to 10,000 mg/l). In addition, desalination technology has improved a great deal in the past decade making desalination of brackish water a cost effective solution for obtaining additional sources of water supply.

Desalination of brackish water is becoming common in Florida, Texas, and California. Other states are now beginning to look at their brackish water aquifers as potential future supplies of potable water.

Improving the Capacity of Mississippi’s Rural Water Associations Through Board Management Training

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Barrett J.

The Mississippi legislature enacted legislation designed to increase the capacity of Mississippi’s rural water associations’ boards and small municipal water systems’ government officials to provide safe drinking water and be aware of the technical and legal responsibilities assumed by these individuals. This legislation mandated that the Mississippi State Department of Health (MSDH), in cooperation with other organizations such as the Mississippi Rural Water Association (MSRWA), provide training to the governing bodies of these systems. To this end, the MSDH contracted with the Mississippi State University Extension Service (MSUES) to develop training curricula and provide coordination and evaluative services to facilitate the provision of quality training opportunities accessible to clientele across the state. Furthermore, partnerships between MSUES, MSRWA, the Mississippi Water and Pollution Control Operators Association, and the Community Resource Group, have resulted in the development of several cutting edge curricula that have been nationally recognized.

A New Hydro-Enforced, 1:24,000 Digital Elevation Model for Mississippi

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Steil J., Walker S.

A new, 10 meter, statewide, hydro-enforced, digital elevation model [DEM] was recently developed by the Mississippi Automated Resource Information System [MARIS] in cooperation with the USGS to better support modeling efforts than the previous 30 meter DEM. The utility of the old 30m DEM was limited by scale, artifacts of processing, and substantial data exclusions such as the Tenn-Tom Waterway and significant migration of the Mississippi River. The new model was developed over a number of years beginning with Mylar separates of 7.5 minute quadrangles. Mylar separates were scanned, vectorized, and resulting lines tagged with elevation values and other attributes. As contour lines are not contiguous across individual quad maps, each contour was connected to the contour of the adjacent quad to create a continuous line for a seamless coverage. Carrying contours were added throughout the state to ensure proper hydrologic modeling. Digital Rater Graphics [DRG’s] were also available to provide clarification for incorrectly tagged elevation values especially at quad boundaries. The 2007 National Aerial Imagery Program [NAIP] 1 meter imagery was used to perform the inclusion and proper placement of the Tenn-Tom Waterway as it was not included in many of the original quadrangles. NAIP imagery was also the basis for correcting the placement of the Mississippi River which had migrated up to 5 miles from the position on the original 7.5 minute maps. Some corrective hydrologic changes were made to the 1:24,000 National Hydrologic Dataset [NHD] to provide more accurate modeling. Partially as a result of this project, MARIS has become the steward of the NHD for Mississippi. Preliminary geometric changes were made to the NHD to reflect changes in the landscape since the publication of the quad maps. These changes were most common in the Delta region and will be incorporated into the official NHD. Due to software limitations, each county was processed separately with a 400 meter buffer. The ESRI Topo-to-Raster command was used to generate each county DEM. Each County was checked by USGS at Rolla, MO. The final DEM’s are included as part of the official National Elevation Dataset [NED] and are available for download from USGS or MARIS www.maris.state.ms.us/HTM/DownloadData/DEM.html.

Transport of Non-Point Source Contaminants Through Riparian Wetlands in the Mississippi Delta Region

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Noakes E., Davidson G.R., Wren D.G., Utroska S.G.

A joint research group at the University of Mississippi and the USDA ARS National Sedimentation Laboratory has been investigating the fate and transport of non-point source contaminants entering riparian wetland systems from agricultural lands. Results to date suggest that short-term studies documenting sequestration of chemically persistent contaminants in riparian wetlands are not sufficient to document long-term containment of these substances. In previously reported work, elevated concentrations of Pb and As were found at particular depths in open-water sediments in Sky Lake, but not in contemporaneously deposited sediments in the surrounding wetlands. Depositional dates of the zones of elevated concentration, based on ²¹⁰Pb and ¹³⁷Cs measurements, were consistent with the timing of lead arsenate use in the vicinity. The absence of similar concentration spikes in the wetland sediments led to the working hypothesis that contaminants such as Pb and As may be initially scavenged from water flowing through a riparian wetland, but over time are flushed out into adjacent lakes or streams. Within the wetland, seasonal inundation and aeration results in decomposition of litter, remobilization of contaminants bound to organic matter, and redistribution by rising and falling water levels. Permanent sequestration occurs only with burial in the perennially flooded open water environment. The study has been expanded to additional lake-wetland systems in the Mississippi Delta region to determine if evidence of long-term flushing of contaminants from riparian wetlands is a common occurrence.

Climatological and Cultural Influences on the Potential for Conservation of Groundwater in the Mississippi Delta Shallow Alluvial Aquifer by Substitut

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Wax C.L., Pote J.W., Merrell T.L.

The shallow alluvial aquifer in the Mississippi Delta region is heavily used for irrigation of corn, soybeans, and cotton, as well as for rice flooding and filling aquaculture ponds in the prominent catfish industry. Water volume in the aquifer is subject to seasonal declines and annual fluctuations caused by both climatological and crop water use variations from year-to-year. The most recently documented water volume decline in the aquifer is estimated at 500,000 acre-feet.

Available climate, crop acreage, irrigation water use, and groundwater decline data from Sunflower County were used to construct a model that simulates the effects of climatic variability, crop acreage changes, and specific irrigation methods on consequent variations in the water volume in the aquifer. Climatic variability was accounted for by predictive equations that related annual measured plant water use (irrigation) to growing season precipitation amounts. This derived relationship allowed the application of a long-term climatological record (48 years) to simulate the cumulative impact of climate on groundwater use for irrigation.

Use of the model to simulate changes in irrigation methods and crop acreages from 2008 through 2055 shows potential to stabilize the water volume in the aquifer through implementation of various management strategies. Four scenarios of water management were simulated—static land use/water use in 2006, total efficient irrigation methods, total inefficient irrigation methods, and enhanced surface water use when available in place of groundwater for irrigation. These simulations illustrate the power of the model to assess the long-term impact of climatic variability and changes in the cultural practices on groundwater use in the region. The model is therefore a tool that will be useful in making management decisions that will allow sustainable use of the groundwater resource.

Runoff Modeling of the Luxapallila Creek Watershed Using Gridded and Lumped Models

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Diaz-Ramirez J.N., Johnson B.E., McAnally W.H., Ramirez-Avila J.J.

The Northern Gulf Institute is funding a project focus in improving watershed-wide decision support for resource management agencies; one of the tasks in this project is define the sensitivity of rainfall-runoff results to use of advanced tools, such as the Corp’s distributed hydrologic model Gridded Surface Subsurface Hydrologic Analysis (GSSHA) and the EPA Hydrologic Simulation Program—FORTRAN (HSPF). GSSHA is a physics based watershed model simulating 2D overland flow, 1D channel flow, and surface water/groundwater interaction. The HSPF software is a conceptual, continuous, lumped parameter watershed model that has been extensively used around the world since 1980. This study evaluates the GSSHA and HSPF runoff performance in the Luxapallila Creek watershed, Alabama and Mississippi. The 1,851 km² watershed drains into the Tombigbee River. Six NOAA raingauge stations are used as hourly input precipitation. Land use distribution using the 1980 GIRAS database shows 73% forest, 20% agricultural land, and 6% wetlands. USGS 30-m resolution digital elevation models (DEMs) are used to delineate and calculate physiographic parameters (e.g., area, slope, and length of slope). The State Soil Geographic (STATSGO) database depicts mainly sandy loam soils. The GSSHA model grid size is 100 m x 100 m, resulting in 185,816 grids. The HSPF model is divided in 50 subwatersheds. Daily streamflow data collected by the USGS at the 02443500 station are used for model evaluation. The Web-based hydrograph separation system (WHAT) is used to calculate runoff and baseflow from observed streamflow data. Observed and simulated runoff data are evaluated using the following statistics: peak error, volume error, flow error, and peak time error. Four storm events are analyzed for the period 01/01/1989 to 03/31/1989. GSSHA peak, volume, and flow errors were around half of HSPF results. Both models showed ahead peaks of one day. However, the GSSHA model results matched the peak of two out of four storm events. The HSPF model runs faster than GSSHA (5 seconds vs 20 hours). GSSHA and HSPF groundwater modules will be setup and evaluated.

Detection of Salmonella spp. from Mississippi Coastal Waters and Sediment

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Carr M.R., Ellender R.D., Flood C.

Traditionally, the examination of individual pathogens for assessment of water quality has not been employed. This is mainly due to the cost and time requirements required to perform the appropriate morphological and biochemical analysis for positive identification of these pathogens. However, the employment of molecular analysis techniques supplemented with traditional techniques allows for more rapid and accurate identification. The main goal of this research is to determine if the marker stn, which codes for an enterotoxin gene specific for salmonella, is present within Mississippi Gulf Coast waters and creek systems, which flow into the Gulf. This research also is aimed at determining if the salmonella marker is present within coastal sediments. Environmental factors such as salinity, temperature, tidal currents, and significant weather related events will be examined to understand the relationship to the presence of the salmonella marker. Examination of salinity’s effect on both laboratory grown and environmentally isolated Salmonella indicates a difference in the survivability of this pathogen within given concentrations of NaCl in situ. Analysis of Salmonella subspecies in coastal waters and sediments using both traditional and genetic analysis has demonstrated that this bacterium is frequently found in samples from fresh water creeks but is found infrequently in coastal waters. Further, sediment samples to date have not revealed the presence of Salmonella, implying that this environment is not conducive to the survivability of this animal pathogen.

Sources and Transport of Total Nitrogen from Major River Basins of the South-Central United States, 2002

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Rebich R.

A spatially-referenced regression on watershed attributes (SPARROW) model was developed for a 2002 base year for streams in the Lower Mississippi, Arkansas-White-Red, and Texas-Gulf River basins to describe total nitrogen loadings to the northwestern Gulf of Mexico. Ultimately, model results may be used to help develop water management plans to reduce, control, and mitigate nutrient inputs throughout the study area. Total nitrogen loads and yields generally were highest near streams in the eastern part of the study area in the Lower Mississippi basin and along reaches near the Texas and Louisiana shoreline. The highest individual source of nitrogen for the study area was from wet deposition of total inorganic nitrogen, which accounted for 36 percent on average of total nitrogen in streams from the study area. Land application of manure from confined feedlots and manure generated in pastures accounted for 22 percent, nitrogen fixation from fertilizer applications accounted for 17 percent, and nitrogen from commercial fertilizers accounted for 12 percent on average of total nitrogen in streams from the study area, which combined totaled 51 percent from agricultural and pasture land uses. Urban sources of nitrogen totaled about 13 percent on average of total nitrogen in streams from the study area, of which urban nonpoint runoff accounted for 9 percent and municipal and industrial point sources about 4 percent.

For the Yazoo River basin in northwestern Mississippi, preliminary estimates of total nitrogen load and yield were about 21,300 metric tons and about 0.64 metric tons per square kilometer, respectively, both of which agree with literature estimates for the sampling station located near the mouth of the Yazoo River prior to release into the Mississippi River. The total nitrogen load from the Yazoo represents about 2.2% of the total nitrogen load of the Mississippi River near its mouth. Nitrogen from atmospheric deposition accounted for about 25 percent of the total load leaving the Yazoo River basin. Agricultural sources accounted for about 67 percent of the total load: 31 percent by commercial fertilizers, 30 percent by nitrogen fixation from fertilizer applications, 5 percent from pastures, and 1 percent from land application of manure from confined feedlots. Urban sources of nitrogen accounted for the remaining 9 percent of the total load from the Yazoo River, of which about 5 percent came from municipal and industrial point sources and 4 percent came from urban nonpoint runoff.

Hydrogeology of the Central Delta (East-Central Sunflower County and West-Central Leflore County)

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Byrd C.B.

For the last several years there has been growing concern regarding the declining water levels in Mississippi River Valley alluvial aquifer (MRVA) in the central Delta. Analysis of water levels alone does not answer the question of how much water is actually remaining in the aquifer. The only way to determine this is to know where the base of the aquifer is in relation to the water level at any one site. Therefore, in the summer of 2004 staff of Mississippi Department of Environmental Quality’s Office of Land and Water Resources (OLWR) began a drilling program to gather this type of information.

Twice each year, staff of the Yazoo-Mississippi Delta Joint Water Management District (YMD) collects water level data from wells screened in the MRVA throughout the entire Delta. Most of the drill sites for this project have been very near some of these wells. The minimum depth drilled at all the sites has been 300 feet. This depth allows not only the entire thickness of the MRVA to be penetrated, but a portion of the underlying formation, as well. Data collected from the water level measurements and drilling enables changes in the saturated thickness of the aquifer at each of these MRVA well sites to be monitored through time.

Throughout the Delta, the surface of the formation(s) underlying the MRVA is an erosional surface; therefore, the contact between the two is an unconformity, resulting in an extremely variable MRVA thickness. Most publications report that the average thickness is approximately 135 to 140 feet. In the project area the average depth of the base of the aquifer is 131 feet below ground surface, with the range of depth between 90 and 166 feet. The water level in the MRVA is approximately 50 feet below ground surface. As most irrigation / catfish culture wells have 40 feet of screen, the most serious scenario is where these wells are screened where the MRVA base is less than 100 feet below ground surface. At these sites, the static water level is either only a very few feet above the top of the well screen or at the top of the screen; and during periods of pumping, the water level is below the top of the screen.

Continued investigation of the geology is an important key to understanding the hydrology of the alluvial aquifer in this area. A better understanding of how this aquifer system works will allow officials to properly and effectively manage this tremendous resource.

A Study of the Effectiveness of Various Sedimentation Solutions and Practices

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Davis T.

This report will show the effectiveness of various types of solutions and practices used to reduce, prevent or change sedimentation patterns within areas of navigational interest. Most modern shipping facilities maintain deeper depths than occur naturally to accommodate the size of the world’s ever growing merchant vessel. Deepening of such facilities such as anchorage basins, ship channels, etc are usually met with sediment deposition, which must be removed or prevented to maintain efficient shipping operations. Maintenance dredging has become the primary tool for the upkeep of underwater navigation dimensions, but it also has a number of downfalls in its operation, which has become more prevalent over the years. Likely, the most obvious problem with dredging is the lack of a permanent solution, for maintenance dredging removes unneeded sediment rather than addressing the processes creating deposition. Many other concerns are associated with maintenance dredging such as: expensive operation costs, difficulty to secure small contracts, downtimes in shipping operations and worries of ecological distress. These problems have created interest in solutions or practices to reduce or prevent the amount of sediment deposition within maintained depth facilities and ultimately reduce the amount of maintenance dredging needed, which may result in significant economic benefits.

Proceedings of the 39th Annual Mississippi Water Resources Conference

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: .

Gulf Coast Watersheds and Water Education: Outreach Alignment and Best Practices

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Clary R.M., Brzuszek R.F.

Previous research (Fulford, Brzuszek, & Roberts, 2008) assessed the impact of ordinances, outreach, and enforcement on the resiliency of the northern Gulf Coastal watersheds. Four watersheds in Louisiana, Mississippi, Alabama, and Florida were selected, and 22 non-governmental organizations (NGOs) in the target watersheds were surveyed with regards to water quality monitoring, environmental education, and watershed management. Detrended Correspondence Analysis (DCA) revealed that the most relevant programs for each watershed varied. Whereas Tchefuncte/Bogue Falaya’s NGOs (LA) tended towards a management plan, the Biloxi River Watershed (MS) focused upon conservation easements and managing land restoration. The Fish River Watershed (AL) exhibited more centralized efforts with a tendency toward conservation, partnerships, and policy. The New River Watershed (FL) was strongest toward development review and education. Our current research extended the results of this initial study to investigate how the focus of each watershed reflected or paralleled their state’s educational goals, benchmarks, and grade level expectations. The educational programs were also analyzed for correspondence to the National Science Education Standards. We included those educational outreach programs aimed toward K-12 students, and analyzed the NGOs’ educational products for alignment with state curricula and national science standards. Additional investigation of other watersheds’ educational programs (e.g., Chesapeake Bay) provided benchmarks against which the northern Gulf Coast watershed programs were compared. Our research resulted in the identification and development of best practices for the implementation of effective Water Education programs that include ecology, water management, and water quality focus.

Collection of Hydrologic Data on Tidally Affected Streams

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Runner M.S., Massingill D.K.

The U.S. Geological Survey began collecting streamflow and other hydrologic data in Mississippi in the late 1800’s. Until recent advances in acoustic technology and its application to hydrologic data collection, it was difficult to collect accurate streamflow data on rivers and streams where stage-discharge relations were affected by varying tide. The greater the tidal affect, the more difficult the data collection. On streams where tides cause the flow to fully reverse, the collection of reasonably accurate continuous data was practically impossible.

By using acoustic technology to collect time-series velocity data and make discharge measurements, the U.S. Geological Survey now operates and maintains four continuous-record surface-water discharge stations, and an additional station where the technology is used to monitor bed scour at bridge piers. At one of these stations, the varying tide primarily affects periods of low flow. At the remaining four stations, the flow fully reverses direction as the tide changes. The streams range in size from large rivers such as the Pearl and Pascagoula Rivers, to small first order streams such as Bayou Heron in the far southeastern part of the State. Data also were collected at monitoring stations (which are now discontinued) on the Escatawpa and Jourdan Rivers. It has been observed that the smaller the stream and corresponding flow, the greater the effect the tide has on the stream, and not surprisingly, the more difficult the data collection.

The computation of discharge on a tidally affected stream requires the collection of data to develop relations between the stage, or water level, and the cross sectional area, and between an index velocity measured by an in situ velocity sensor and an average velocity computed from a streamflow measurement. It is the collection of these two data sets and the product of the computed area and average velocity that provides continuous discharge values.

Conjunctive-Use Optimization Modeling of the Mississippi River Valley Alluvial Aquifer: Evaluation of Groundwater Sustainable Yield

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Czarnecki J.B.

The Mississippi River Valley alluvial aquifer (the alluvial aquifer) is a water-bearing assemblage of gravels and sands that underlies about 32,000 square miles of Missouri, Kentucky, Tennessee, Mississippi, Louisiana, and Arkansas. The alluvial aquifer ranks third among the most productive aquifers in the United States. In 2000, more than 9 billion gallons per day of water were pumped from the alluvial aquifer by more than 45,000 wells, primarily for irrigation and for fish farming. Since the widespread agricultural use of the aquifer began, several large cones of depression have formed in the potentiometric surface, resulting in lower well yields and degraded water quality in some areas.

Conjunctive-use optimization modeling was done to assist water managers and planners by estimating the maximum amount of groundwater that hypothetically could be withdrawn from alluvial wells and from hydraulically connected streams without violating hydraulic-head or streamflow constraints. Optimization models showed that continued pumping at 1997 rates are unsustainable without violating head constraints imposed as a part of Arkansas’s Critical Groundwater Area criteria. Streamflow constraints specified within the model were based partly on minimum flow requirements for maintaining either navigation requirements, water quality, or fish habitat. Continuously pumping at 1997 rates resulted in water levels dropping below the hydraulic-head constraints (either half the aquifer thickness or 30 feet of saturated thickness), making those rates unsustainable. Optimized sustainable pumping was obtained such that water levels were maintained at or above the hydraulic-head constraints, and streamflow was maintained at or above minimum flow requirements. No single value of groundwater sustainable yield exists, as it depends on the specification of water-level and streamflow constraints, and the specification of potential groundwater and stream-withdrawal locations and their maximum allowable withdrawal rates.

The Effect of Policy and Land Use Change on Water Quality in a Coastal Watershed City: An Analysis of Covington, Louisiana

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Langley K., Schauwecker T., Wilkerson W., Walker J.

There is currently a great need to expand the understanding of land use policy’s impact on water quality. The purpose of this work is to examine local policy in Covington, Louisiana in order to assess its impact on land use. Land use is then analyzed to reveal effects on water quality. Water quality should then be used to dictate policy in a feedback loop, but that is not currently happening. Methods used include reclassifications of land use categories within a Geographical Information System and analysis of changes over a four year period. Policy is assessed using two instruments. The first is a pre-existing evaluation method devised by The Center for Watershed Protection. The second is by a more flexible and generalized apparatus developed by staff and faculty in the Department of Landscape Architecture at Mississippi State University. Three water quality parameters are examined for impairment due to their known correlation to urban runoff. Nonpoint source pollution from agriculture is also discussed, however, for analysis of policy and land use in the City of Covington, this is less of an issue.

While it has been determined that Covington’s water quality related policy is insufficient and surface waters are impaired, there are a great deal of extenuating circumstances that impact water quality both in and around the city. Changes to current monitoring efforts and policy drivers are discussed along with suggested improvements that could be made to altered landscapes and current governance.

Arkansas&rsquo Expanded Relational Water-Use Program

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Holland T.W.

The Arkansas Water-Use Program is a cooperative effort between the Arkansas Natural Resources Commission (ANRC) and the U.S. Geological Survey (USGS). Site-specific data for several water-use categories are reported annually by water users and are electronically stored. Water users that withdraw 1 acre-foot or more of surface water per year or operate wells with the capability of pumping 50,000 gallons of ground water per day or more must report their withdrawals. Site-specific water-use data for irrigation, livestock, duck hunting clubs, public supply, commercial, industrial, mining, and power generation are stored in the Arkansas Water-Use database developed and maintained by the USGS Arkansas Water Science Center (AR WSC). Data for the irrigation, livestock, aquaculture, and duck hunting club categories are reported through the Conservation District offices in selected counties. Users report data for about 54,000 agricultural measurement points through the County Conservation District offices via a secure internet Web page that is the entry point into the Arkansas Water-Use Data System. Water-use data for the other categories are reported directly to the Arkansas Natural Resource Commission on paper registration forms generated by AR WSC staff as output from the data base management system. These forms are mailed out by ANRC staff to about 1,200 additional water users that do not report their water use via the Web. The completed registration forms are returned to U.S. Geological Survey for entry in to the Arkansas Water-Use Data Base System. The amounts of water withdrawn, sources of water, how the water was used, and how much water was returned are available to water-resources managers and policy makers through retrievals from the Arkansas Water-Use Data Base System.

Expansion of the Arkansas Water-Use System began 3 years ago for multiple reasons. ANRC needed a viable way to store and retrieve water-well construction information that Arkansas law requires be reported to the Arkansas Water-Well Commission (a component of ANRC) and, the understanding of ground-water use would be enhanced with a relational link to well construction information; and, a better understanding of hydrogeologic structure would further compliment ground-water use understanding and provide enhanced information concerning water-bearing zones contributing to wells. Consequently, tables have been added to the system as a repository for water-well construction data and a Well Log Archive. Staff at the ANRC enters data into the water-well construction tables. Construction data for approximately 57,000 wells reside in the database at this time. Well log archiving is a continuing effort, in the ANRC/USGS cooperative program, to archive and interpret borehole geophysical logs. As a part of our continuing cooperative program, well logs for a few Arkansas counties are scanned and geo-referenced each year - 12 counties have been completed to date. The tops of aquifers and confining units are interpreted from these logs for the purpose of creating a digital framework of the subsurface. This framework of hydrogeologic units is used in conjunction with a reported water-use location to determine/verify contributing aquifers. This is a "visual" process, using an interactive mapping application.

Sulfate Removal From Ground Water

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Bricka R.M., Stokes B.

A process to remove sulfates from ground and surface water to meet required drinking water standards has been completed. Several options were researched, including ion exchange, electrodialysis, electrodeionization and other membrane technologies. In evaluating each process, economical, environmental, health and safety issues were considered. A primary concern during assessment was the feasibility of scaling up a bench scale process to a system that can produce hundreds to thousands of gallons. While many of these are innovative technologies, ion exchange is a more commonly accepted process and is suitable for large scale production because of the lower operation costs.

This paper describes the process by which ion exchange technology occurs as well as the recommended design for scale up. The prototype design includes two columns packed with anion exchange resin. For the chosen set-up, one column will purify water, and the other column can be regenerated without interrupting continuous production. Multiple equilibrium and dynamic tests were performed to calculate the sulfate absorption capacity of the resin and determine the optimum treatment rates for maximum efficiency. The Environmental Protection Agency has numerous regulations and standards providing recommended contaminant levels of sulfates in drinking water. These standards provide a basis for testing and design. The process was scaled to purify 120,000 gallons of water per day while minimizing the concentrations of sulfates and other dissolved solids. All equipment, product, and operational costs were calculated and evaluated. Several waste treatment options were also evaluated, and a recommended design to employ evaporation ponds was chosen based on geographic location and arid climate. In the chosen waste treatment option, all regenerative waste is sent to an evaporation pond to recover and dispose of excess salt. The process of ion exchange successfully removed an adequate amount of sulfates and was proven to be a feasible solution for water treatment in areas with high sulfate concentrations.

Drainage Improvement Project Development for Successful Hazard Mitigation Funding

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Talbot M.T., Quarles J.E., Bass D.L., Jourdan N., Swagart G.

Over 100 drainage improvement project proposals were considered for Katrina Hazard Mitigation Grant Program (HMGP) funding in 2008 and 2009, by the Mississippi Emergency Management Agency, with assistance from FEMA. Many of these project proposals displayed technical merit and detailed the scope of work and estimated project costs. Completion of these projects could have reduced future flood levels and associated future flood damages in many communities. However, most of these proposals had insufficient damage history data needed to determine the benefits of the mitigation projects. Benefits are defined as avoided damages, disruptions, losses, etc., as a result of the mitigation. For HMGP funding approval, the FEMA Benefit Cost Analysis (BCA) musts show that the benefits of a project are equal to or exceed the project cost. The FEMA Damage-Frequency Assessment (DFA) BCA module is used for localized drainage improvement projects when Flood Insurance Study (FIS) or comparable data are not available. This paper presents an overview of the DFA module and the necessary documentation requirements. Further, suggestions for developing routine collection of the needed documentation to apply the DFA module for drainage improvement projects are outlined. This information will assist communities to be better prepared to successfully apply for HMGP funds that might be available in the event of future disaster declarations.

Preliminary Assessment of Ecosystem Services Provided by Moist-Soil Wetlands

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Spencer A.B., Kaminski R.M.

Management of moist-soil wetlands is intended to promote seed and tuber producing annual vegetation and production of aquatic invertebrates, both of which provide critical food for waterfowl and other wetland wildlife. Moist-soil management of marginal cropland and other similar lowlands can potentially enhance quality of discharge water and run-off in agricultural landscapes such as the Mississippi Alluvial Valley. Seasonal decay of wetland vegetation sustains nutrient cycling and is the foundation of detrital based food webs in these systems. Crayfish (Procambarus sp.) populations are dependent upon the detrital based food web, provide a source of protein and other nutrients for wetland wildlife, and can be harvested for human consumption. During late-winter to early summer 2009, we monitored water quality, detritus accumulation and decay, invertebrate abundance, and crayfish harvest characteristics in public and privately managed moist-soil wetlands throughout Mississippi. The results from our monitoring efforts will be used to estimate potential ecosystem services provided by moist-soil management such as sediment abatement, nutrient retention, invertebrate production, and crayfish harvest. Demonstrating multiple ecological and economical benefits of moist-soil wetlands may encourage landowners to develop and manage natural wetlands within guidelines of conservation programs such as the Farm Bill’s Wetland and Conservation Reserve Programs.

Science Education on the Tennessee-Tombigbee Waterway: An Outreach Effort for K-12 Students and Teachers in Northeast Mississippi

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Langley K., Kerzel D.

Mississippi University for Women’s (MUW) Science Education on the Tennessee-Tombigbee Waterway project endeavors to provide enhanced science education opportunities for K-12 students and teachers in northeast Mississippi. As an institution, MUW has established itself as a leader in Mississippi by offering relevant and innovative educational outreach programs. In particular, the Department of Sciences and Mathematics has a strong track record spanning over a decade of providing high quality science and mathematics enrichment for elementary, middle, and high school groups. By working to increase the knowledge base in science and mathematics, our programs will enable Mississippians to better meet the challenges of the future.

In this program, hands-on science and mathematics activities for students and teachers will be the central focus. These programs will be made useful to participants in one of two contexts: (1) how information presented can be used to improve the quality of life for people, and (2) how it can be used to benefit the environment. Workshop activities will take place primarily at the Plymouth Bluff Environmental Center, a learning facility which is part of MUW. The MUW Explorer, a 36’ by 10’ pontoon boat which has been designed as a floating teaching laboratory, will be used to engage participants in science activities on the Tennessee-Tombigbee Waterway. Other activities will be outdoors at Plymouth Bluff and in the classroom setting there. These activities will allow the participants to construct their own understanding of science in a real-world setting. Specific topics covered include forest and aquatic ecology, wildlife biology, geology, astronomy, and sustainable living strategies. Much of the program will focus on hydrology workshops conducted on the waterway. These programs will educate teachers and students on chemical and physical properties that dictate water quality, aquatic macroinvertebrates and benthic index concepts, nonpoint source pollution caused by rural and urban landscape alteration, responsible watershed management, and stream morphology, ground water concepts, and the importance of wetlands.

Participants will be evaluated to assess the success of the program in terms of teacher competency and utilization of material in classrooms and student interest and performance in science. Demographic information will also be collected and analyzed to assure that people of all racial, ethnic, socioeconomic, and ability levels are taking advantage of our programs. Work for this entire outreach project has been supported by a generous congressionally funded grant.

Restoring Canebrakes to Enhance Water Quality Along the Upper Pearl River

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Jolley R., Neal D., Baldwin B., Ervin G.

Large stands of rivercane [Arundinaria gigantea (Walt.) Muhl.], called canebrakes, initially covered millions of acres in the southeast US, playing a pivotal role in the hydrology, landscape ecology, and the cultural history of the First Nations of the Southeast. Because canebrakes are composed of very dense stands of rivercane, they act as ideal riparian buffers, dispersing overland flow, increasing soil porosity, and stabilizing streambanks. Unfortunately, large canebrakes have all but disappeared from the landscape due to overgrazing, agriculture, and altered fire regimes. In an effort to enhance water quality and wildlife habitat along the upper reaches of the Pearl River, a rivercane restoration project was initiated in June 2008. Over 1,000 rivercane seedlings were planted at eleven locations along a half-mile stretch of the Pearl River on land belonging to the Mississippi Band of Choctaw Indians (MBCI). Planting sites were selected as those susceptible to erosion (outer bends) and deposition (inner bends) in order to monitor the effect of canebrake establishment on stream bank stabilization. An additional nine sites were chosen along this same stretch for comparison (three sites with established rivercane and six without). Sediment markers were installed to monitor sediment depths within and outside of planting areas. Additional sediment markers were also inserted horizontally into eroding banks to monitor bank-sloughing along planted areas. Preliminary data indicate low survivorship in plantings at elevations susceptible to extended periods of inundation (<3 m above normal flow). Both planted and unplanted banks show moderate rates of erosion. Due to slow initial growth, rivercane seedlings may require several years to form effective riparian buffers.

Collective Action Regimes in Inland Marine Port Clusters: The Case of the Tenn-Tomm Waterway System

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Miller C., Stich B.

This paper analyses the competitiveness of the public-private Tennessee-Tombigbee Waterway system from a cluster perspective, discussing the importance of local governance and collective action regimes for the competitiveness of the cluster. The case study of the Tenn-Tomm port cluster shows how the collective action regimes have developed in this cluster. This study compares the Tenn-Tomm to a similar study done by de Langene and Visser (2005) comparing the Lower Mississippi port cluster to the seaport cluster of Rotterdam. A number of collective action problems require effective collective action regimes that render significant public benefits at the cluster level. Several public policy proposals are formulated to improve the quality of the public-private collective action regimes and hence enhance the performance of the Tenn-Tomm waterway system.

Hydrologic Services Provided by the National Weather Service

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Reed D.B., Graschel J.

The National Weather Service (NWS), part of the National Oceanic and Atmospheric Administration (NOAA), is responsible for providing river and flood forecast sand warnings across the country to save lives and property. The NWS has 122 Weather Forecast Offices (WFOs) across the country that maintain a 24-hour weather watch and provide watches and warnings for severe weather and flooding. The NWS operates 13 River Forecast Centers that model the most important portions of the hydrologic cycle and use those models to provide forecasted river levels for five days into the future.

The backbone of the NWS Hydrologic Services is the issuance of river forecasts at over 4,000 locations. At these sites, the NWS issues forecasted river stage levels for the next five days. To run hydrologic models to support the issuance of these forecasts, the NWS must develop estimates of precipitation on a 4x4 km grid each hour. These quality controlled precipitation estimates are posted to the Internet for customers and the general public to use.

To complement river stage forecasts, the NWS also provides individualized hydrologic support to the emergency management community and other federal, state, and local water resource agencies. This support may take the form of customized hydro-meteorological briefings which can be disseminated through the web, telephone and/or chat services. In high impact events, the NWS may also station a hydrologist or meteorologist at a state or local emergency management office to provide a heightened level of support.

Identification of Streambank Erosion Processes and Channel Changes in Northeastern Mississippi

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Ramirez-Avila J.J., Langendoen E.J., McAnally W.H., Martin J.L., Ortega-Achury S.L., Diaz-Ramirez J.N.

Identification of streambank erosion processes is important for determining suitable measurement techniques and for choosing appropriate stream remedial measures. Sediment loads from watersheds located in Northeastern Mississippi can have contributions from stream channel degradation as large as 90%. Town Creek watershed is an experimental watershed in the Southeastern Plain Ecoregion of Mississippi (Ecoregion 65). Northern headwaters in Town Creek located within the Black Prairie Subecoregion present incised streams with unstable active bank profiles. The most common gravitational failure mechanisms are slab failure, soil fall, and cantilever failure, accompanied by a basal clean out process when stormflow events occur. An active agricultural land use near streambanks with limited or reduced presence of riparian zones increases the streambank instability and favors gully erosion activity. This condition is predominant along the different headwater reaches. The middle 20 km of the principal channel system is located within the transitional zone between the Tombigbee Hills and the Black Prairie subecoregions. Wide stable channels showing evidence of streambank erosion induced by fluvial erosion, shallow slides, and rotational failures are mixed with natural, vegetated zones and regions with sediment deposition on bed and streambanks. Especially along this section of the principal channel, sediment bed deposition and erosion are significantly modified seasonally by flow conditions. Low flow velocities and sediment deposition occur on the inside of incipient meander bends in the sinuous reach, along the downstream most 10 km before the outlet at the Tombigbee River.

Environmental Impact and Disposal of CCA-Treated Wood Waste

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Parker A.M., Bricka R.M.

Wood products are treated with preservatives to prohibit degradation by a multitude of organisms and to prolong the products’ life in adverse environments. The most widely used wood preservative since the early 1970’s has been chromated copper arsenate (CCA), resulting in nearly 80% of all treated wood products in North America being treated with CCA. In 2002 the wood preservative industry voluntarily adopted a restricted consumer use policy, and by late 2003 CCA-treated wood was limited to industrial applications due to concerns over possible exposure to toxic substances. Due to the restricted use policy, it is estimated that as much as 24 million tons of CCA may be available for disposal by 2020. Until recently, landfilling the out of service CCA-treated material was the accepted method of disposal. However, problems associated with soil and groundwater contamination, directly linked to the leaching of CCA-metals from landfills, have generated the need for a more effective and efficient disposal method for CCA-treated wood waste. Alternative approaches to CCA-treated wood disposal include utilizing advanced sorting techniques to place the treated wood waste in hazardous waste landfills, using chemical extraction to remove the CCA-metals, and employing thermochemical conversion processes to isolate the CCA-metals and reduce waste volume. This paper will provide detailed information on the environmental impact and disposal of CCA-treated wood waste, including environmental standards, test methods, and discussion of on-going research.

Life Cycle Assessment of Wood Pyrolysis for Bio-Oil Production

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Thomas H., Bricka R.M.

The Department of Chemical Engineering is evaluating a pyrolysis process for the conversion of wood into bio-oil or pyrolysis oil for use in wood treatment. Historically, wood has been treated with a mixture of copper, chromium, and arsenic. Due to the toxic substances and potential leaching into the ground water supply, CCA has been banned from use in the U.S. As older wood is being taken out of service, new methods of preservation are being explored for the wood being put into service. The resulting bio-oil from this pyrolysis process has shown promise as a wood preservative.

Before full scale production can begin a Life Cycle Assessment (LCA) will be performed on the process. LCA is a cradle-to-grave analysis involving the feedstock and materials of construction as well as storage, transportation, and disposal issues. It helps quantify emissions into the air and ground water. The results of the LCA model will be used to determine the economic viability of the process, the energy "break-even point," and the carbon footprint of the process. LCA can also be used to aid in future management and planning for the process.

Recycling CCA-Treated Wood Waste: Design and Operation of a Laboratory-Scale Pyrolysis System

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Cook M., Parker A.M., Bricka R.M.

Since the early 1970’s, the most widely used wood preservative has been chromated copper arsenate (CCA), resulting in nearly 80% of all treated wood products in North America being treated with CCA. By the end of 2003 CCA-treated wood was restricted to industrial applications, resulting in a considerable increase in the volume of CCA-treated wood slated for disposal. Landfilling was considered an acceptable means of discarding CCA-treated wood products until recently, as there have been instances of the toxic metals leaching from the landfills and contaminating the surrounding soil and groundwater. It is clear that traditional disposal methods are not adequate and that a safe and efficient disposal method for CCA-treated wood must be developed.

Fast pyrolysis, the heating of biomass at temperatures between 400°C and 650°C in the absence of oxygen, is a promising technology that can be applied to CCA-impregnated wood waste. Pyrolysis of lignocellulosic material produces char, liquid condensate (bio-oil), and non-condensing gases. The focus of this research is on removing the CCA-metals from the treated wood waste while recovering the energy value of the wood. This is accomplished by concentrating the CCA-metals in the bio-oil, for possible re-use in wood preservatives, during pyrolysis. A laboratory scale pyrolysis system, capable of operating in the desired temperature range under atmospheric and vacuum conditions, has been designed. The system is also designed to enable the collection of each pyrolysis product so that complete mass balances on the metals can be performed, tracking the fate of the CCA components. This paper discusses the process of designing and operating the laboratory scale pyrolysis system, as well as preliminary experimental results.

Electrokinetic Treatment of Mercury Contaminated Soil at the Mercury Refining Company Superfund Site

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Lusk R., Bricka R.M.

Mercury contamination due to leakage from industrial processes can result in serious environmental, health, and safety concerns. Traditional methods for the remediation of elemental mercury from contaminated sites include a dig and haul approach (retorting) and/or an isolation approach. However, these methods can be very costly and ineffective with regards to removing the mercury from the contaminated soil. Therefore, a new Electrokinetic Remediation method is proposed in which mercury can be cost effectively removed from a contaminated site in order to be recycled or disposed of properly. This method includes the use of anodes and cathodes installed in the ground throughout the contaminated site to produce an electric field which forces the contaminant to migrate to a specific position in which it can be efficiently removed. The use of several amendments to increase the solubility (and electrokinetic potential) of the mercury in the soil is also researched to determine a most effective and efficient mercury removal scheme. It was determined in batch and continuous electrokinetic cells that a 0.1 M Potassium Iodide, .01 M EDTA was effective in solubilizing and removing mercury below the EPA’s regulatory limit of 31mg/kg.

Evaluation of Phosphate Treatment Methods to Reduce Lead Mobility at Military Small Arms Training Ranges

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Bricka R.M., Blakely J.

The primary goal of the United States Military is to train and equip troops to maintain military readiness to defend the United States and its interests. Small arms range (SAR) training represents a major element in keeping the military ready to accomplish this mission.

Projectiles utilized as part of SAR training have accumulated in the soil at the SARs as a result of many years of use. These projectiles are composed of toxic metals. The projectiles, with weathering, change form allowing the metals to migrate to surface and ground water sources. Due to the toxicity associated with the metals, the SAR may pose a threat to humans and the environment. Current lead remediation techniques are costly and inefficient thus new cost effective remediation techniques must be developed and implemented.

Studies show that the treatment of the soil with phosphate-based binders may react with the metals, which results in lowering the solubility of the lead and other metals. The phosphate based-binders react with the metal ions, such as lead, to form insoluble metal phosphate complexes called pyromorphites as shown in equation 1.

10M²⁺ + 6H₂PO₄^-  + 2OH^-  > M₁₀(PO₄)₆(OH₂) + 12H+   Eq (1).

Several types of phosphate binders can be used to form the desired pyromorphites, however, the kinetics of the reaction depend on the phosphate complex. This may be due to the ability of the specific binder to mix efficiently in the contaminated soil or due to the reactive nature of the specific form of phosphate applied to the site.

This paper presents the results of a study to investigate the effect of phosphates on the lead contained in soils collected at military SAR training areas. Laboratory evaluations consisted of adding various phosphates at different dosages to SAR samples. After treatment the soils were subjected to a series of leaching tests. The result of laboratory effort as well as the planned field activities will be presented.

Possible Correlations Among Simple Visual Disturbance Estimates and Hydrologic and Edaphic Parameters in Forested Headwaters of Mississippi

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Dewey J.C., Ezell A.W., Palmer J.O., Choi B.

Silvicultural BMPs are designed to provide guidelines for maintaining the overall integrity of surface waters by minimizing non-point source inputs of sediment, nutrients and pesticides. Mississippi Forestry Commission guidelines for management of perennial and intermittent stream channels are specific; however guidance recommendations for ephemeral-flow channels are minimal albeit these flow channels are often incipient streams. Measuring the effects of disturbance due to silvicultural activities within and around ephemeral-flow channels on hydrology and soil quality is often time-consuming and cost-prohibitive. This project expands the scope of ongoing research that is currently characterizing the relationships among surface- and subsurface-hydrology, soil physical properties, vegetative communities, and sediment movement in ephemeral-flow and intermittent portions of incipient headwaters in Webster County, Mississippi. Hydrologic and edaphic monitoring began in January of 2007; timber harvesting was conducted in the 4th quarter of 2007; and the site was replanted with loblolly pine in the fourth quarter of 2008. The objective of this study is to characterize disturbance at multiple levels in hydrologically fluid headwater ephemeral areas using a simple visual classification scheme and determine whether correlations exist among observed disturbance levels, surface- and subsurface-hydrology, and selected soil properties.

Use of Borehole Geophysics to Determine Zones of Radium Production in Northern Arkansas

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Hart R.M., Kresse T.M.

Borehole geophysics can be used to identify zones of radium production and can aide in design of new well construction so that radium levels in new wells are minimized. Elevated radium levels in water from deep wells (average depth of approximately 2,000 feet) drilled into the Roubidoux Formation or Gunter Sandstone in northern Arkansas are an ongoing issue. Some wells drilled for public supply use have been abandoned because radium levels exceed the maximum contaminant level set by the U.S. Environmental Protection Agency. The U.S. Environmental Protection Agency has established a maximum contaminant level for combined Ra-226 and Ra-228 in public water supplies of 5 picocuries per liter. Radium levels (of about 6-7 picocuries per liter) in water samples from a public supply well near Hasty, Arkansas, exceed the maximum contaminant level.

Borehole geophysical methods are useful in determining physical and chemical properties of formations and groundwater in and around the well, in addition to aquifer hydraulic characteristics. A suite of geophysical logs that included flowmeter and natural gamma were recently completed by the U.S. Geological Survey Arkansas Water Science Center for a well near Hasty, Arkansas. These data were used to determine zones of flow into and out of the well, as well as the lithology near the flow zones. This information, combined with water-quality data, could provide insight needed to correlate specific lithology or fracture sets with radium levels.

Other wells in northern Arkansas contain elevated radium levels according to the Arkansas Department of Health. Zones of radium production will be evaluated in 3-5 of these identified wells to further correlate elevated radium with specific lithology or fracture sets. The identified lithology and fracture sets associated with the elevated radium can then be avoided or plugged in future well construction to minimize radium levels in those wells.

Using Human Specific Molecular Markers to Monitor Water Quality Along the Mississippi Gulf Coast

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Flood C., Carr M., Ellender R.D.

Our research examines the efficacy of using library independent methods and human specific marker to monitor the water quality of the Mississippi Gulf Coast. The two markers currently employed are Methanobrevibacter smithii and Bacteroides sp. M. smithii represents a methanogen that is commonly found in human feces and sewage. Bacteroides sp. are a major component of the intestinal flora in humans. Our goal is to examine the dynamic relationship of the physical and climatological variables that may influence the presence or absence of these markers in the natural environment. In the future, the inherent survivability of these markers will also be examined with relationship to water temperature, salinity, and turbidity. Temporal spatial relationships of the two markers are considered with respect to the presence or absence at certain collection sites. The collection sites mirror the sites monitored by MDEQ and represent an area of the coast that is commonly used for recreational purposes, but is also frequently closed due to high indicator counts.

An analysis of 12 months of coastal sampling contrasting the average enteroccoccal count at each sampling site, the percentage of times that the M. smithii marker appeared in each coastal sample, and the percentage of times that the Bacteroides marker appeared indicated that there was no statistical difference between the EN count and the percentages of either marker. In addition, there was a significant correlation between the percentage of Bacteroides and the percentage of M. smithii when all samples were grouped (0.9503). An analysis of the enteroccocal counts in creeks which drain into the beech environment revealed a significant difference between those coastal sites influenced by creek water versus those not influenced by creek water (P=0.0531). However, both the M.smithii and Bacteroides markers showed a positive correlation (0.7923) between creek versus non creek sites, demonstrating an apparent influence of the creek water on the presence or absence of the markers in coastal waters.

Water Quality of Least-Impaired Lakes in Eastern and Southern Arkansas

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Justus B.G.

A three-phased study identified one least-impaired (reference) lake for each of four Arkansas lake classifications; three classifications in the Mississippi Alluvial Plain (MAP) ecoregion and a fourth classification in the South Central Plains (SCP) ecoregion. Water quality at three of the least-impaired lakes generally was comparable and also was comparable to water quality from Kansas and Missouri reference lakes and Texas least-impaired lakes. Water quality of one least-impaired lake in the MAP ecoregion was not as good as water quality in other least-impaired lakes in Arkansas or in the three other States; a probable consequence of all lakes in that classification having a designated use as a source of irrigation water. Chemical and physical conditions for all four lake classifications were at times naturally harsh as limnological characteristics changed temporally. As a consequence of allochthonous organic material, oxbow lakes isolated within watersheds comprised of swamps were susceptible to low dissolved-oxygen concentrations to the extent that conditions would be limiting to some aquatic biota. Also, pH in lakes in the SCP ecoregion was < 6.0, a level exceeding current Arkansas water-quality standards but typical of black water systems. Water quality of the deepest lakes exceeded that of shallow lakes. N:P ratios and trophic state indices may be less effective for assessing water quality for shallow lakes (<2m) than for deep lakes because there is an increased exposure of sediment (and associated phosphorus) to disturbance and light in the former.

Evaluating the Role of Groundwater and Surface-Water Interaction on the Transport of Agricultural Nutrients to the Shallow Alluvial Aquifer Underlying

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Barlow J.R., Dalton M.S., Coupe R.H.

Between April 2007 and November 2008, the U.S. Geological Survey (USGS) has collected various hydrogeologic and water-quality data to evaluate the role of groundwater and surface-water interaction on the transport of agriculturally applied nutrients to the shallow (less than 25 feet deep) sand and gravel aquifer underlying the Mississippi Alluvial Plain in northwestern Mississippi. Despite stringent best management practices, agricultural activities seemingly contribute to nutrient and pesticide loads in the region’s groundwater and surface waters. A pervasive, near-surface, semi-impermeable clay layer appears to substantially inhibit movement of nutrients into the shallow alluvial aquifer. However, many streams and ditches are incised below the clay layer into more permeable material, thus suggesting another, more direct route for nutrient transport into the underlying alluvial aquifer. Such transport would be further enhanced by declining water levels in the aquifer. Previous investigations by the USGS showed that during periods of high surface-water flow, groundwater flow reverses direction, and the stream changes from a gaining stream (groundwater flow into the stream) to a losing stream (surface-water flow into the streambed sediments and potentially into the shallow alluvial aquifer). A one-dimensional model developed for the investigations considered only the movement of water in the vertical direction (into and out of the streambed). The present investigation expands on the previous model by evaluating both the vertical and horizontal flow components and couples this information with water-chemistry data.

Management of an Abandoned River Channel Wetland for Mitigation of Nonpoint Source Pollution

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Shields Jr. F.D., Wilson C.N., Bryant C.T., Testa III S.

Reduction of nonpoint source pollutants, principally sediment and nutrients moving from cultivated fields to surface waters, is a major challenge. Remnants of once-extensive natural wetlands occur across the agricultural landscape, and some workers have suggested that these areas might be managed to yield improved wetland function in terms of trapping and retention of nonpoint source pollutants. An existing wetland in a severed meander bend cut off in the 1940s from the Coldwater River in Tunica County, MS was modified by the construction of weirs equipped with water control structures. The wetland was a segment of old river channel about 500 m long and 14 m wide. Inputs to the wetland cell included sporadic flows due to runoff events from about 350 ha of cultivated fields and less frequent but larger flood events from the river. This type of flood event occurred only once during the study.

Weir drainage structures were operated to retain water during March—November, and were opened to allow flow to and from the Coldwater River during December, January and February. Weir elevation during March—November corresponded to a mean water depth of ~ 0.15 m. Volumes of water entering and leaving the wetland cell were estimated for 18 months using measurements made at weirs and at a culvert. Estimates of loads entering and leaving the wetland cell were computed based on concentrations of grab samples collected at the wetland cell inflow and outflow locations.

Water concentrations of sediment and nutrients were generally lower at the downstream end of the wetland cell than in the major inflow, an ephemeral slough. Mean values of turbidity, suspended sediment concentration, and concentrations of filterable and total phosphorus were 25% to 40% lower at the wetland cell discharge weir than in the slough. Mean concentrations of ammonia were 38% lower, but mean nitrate and nitrite concentrations were essentially unchanged by the wetland cell. Comparison of estimated input and output loads during periods when the wetland cell was not flooded by the river indicated that the wetland cell retained about 18% of input suspended sediment, 24% of phosphorus, and 29% of nitrogen input from cultivated fields. Wetland cell sediment and nutrient retention efficiency was greater for drier months, and declined during wetter periods with frequent runoff events.

Methyl Mercury in Water and Fish Tissue in the Lower Yazoo Basin

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Myers K.

Mercury is a leading cause of fish consumption advisories in the United States and is the only metal with a fish consumption advisory in Mississippi. While none of the affected water bodies are within the Mississippi Delta, a 2001 ambient water quality criterion established by the EPA would lower Mississippi’s fish tissue threshold from 1 mg mercury per kg of fish tissue to 0.3 mg methyl mercury per kg of fish tissue. Since studies have shown that nearly 100 percent of the mercury that bioaccumulates in predator fish tissue is methyl mercury, the new fish tissue criterion would become 0.3 mg/kg mercury in fish tissue. The State of Mississippi is expected to implement this new fish tissue mercury criterion within the next year. Implementation will increase the number of water bodies with fish tissue consumption advisories within the State and the Mississippi Delta in particular. Recently the USACE Vicksburg District analyzed the potential for increases in methyl mercury concentrations in surface water and fish tissue based upon completion of the Yazoo Backwater Project’s reforestation component. The analysis used a simplified linear model that compared the potential for changes in methyl mercury production based upon changes in land use, flooded acres, and flood duration. The model predicted that completion of the Yazoo Backwater Project recommended plan and reforestation of up to 55,600 acres of currently farmed agricultural land could have increased methyl mercury production by 3 percent over base conditions. The Vicksburg District’s mercury database includes surface water samples for methyl mercury collected between 2003 and 2008 and mercury in fish tissue samples collected between 1993 and 2008. Surface water samples were collected during flooded conditions in Delta National Forest greentree reservoirs, during flood and non-flood conditions in Delta Nation Forest wetlands, and during summer, non-flood conditions in streams and lakes in the lower Yazoo Backwater Area. The data show that methyl mercury production is highest in areas rich in easily accessible organic matter that undergo extended flooding. Fish tissue mercury concentrations appear to be related to flood duration and the number of acres flooded.

Effects of Transgenic Glyphosate-Resistant Crops on Water Quality

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Cerdeira A.L., Duke S.O.

Glyphosate (N-[phosphonomethyl] glycine) is a highly effective, non-selective herbicide. Herbicide-resistant crop (HRC) has been the most successful trait used in transgenic crops throughout the world. Transgenic glyphosate-resistant crops (GRCs) have been commercialized and grown extensively in the Western Hemisphere and, to a lesser extent, elsewhere. GRCs have generally become dominant in those countries where they have been approved for use, greatly increasing the utilization of glyphosate. Potential effects of glyphosate on ground and surface water are lower than the effects of the most herbicides that are replaced when GRCs are adopted. Perhaps the most positive indirect effect is that GRCs crops promote the adoption of reduced- or no-tillage agriculture, resulting in a significant reduction in soil erosion and water contamination. Glyphosate and its degradation product, aminomethylphosphonate (AMPA), residues are not usually detected in high levels in ground or surface water in areas where glyphosate is used extensively. There are some concerns about AMPA in water since it has higher mobility and persistence in the environment than glyphosate. However, neither glyphosate nor AMPA are considered to be significantly toxic. Of greater concern are the formulation ingredients, which can vary from country to country, from product to product, and even over time with the same product. There is some published evidence that formulation ingredients might adversely affect amphibians in some situations.

A Study of Seagrass, Ruppia maritima and Halodule wrightii, at Grand Bay National Estuarine Research Reserve

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Nica C., Cho H.J.

Seagrass beds provide nursery and foraging habitats for marine life, help improve water clarity, help reduce coastal erosion, and buffer wave energy. Therefore, temporal changes in their distribution and abundance indirectly reflect changes in the habitat quality and environmental health status. Ruppia maritima, the most abundant and common species in the Mississippi seagrass beds, is an opportunistic, pioneer species that is highly dependent on sexual reproduction. In order to provide information needed to identify areas that can support seagrass growth and to understand the temporal variations in the seagrass structures within the areas, we conducted biannual surveys at Ruppia maritima and Halodule wrightii beds in Grand Bay National Estuarine Research Reserve (NERR), Mississippi. We hypothesized that there were significant spatial and short-term fluctuations in the coverage of Ruppia/Halodule beds. Three-way ANOVA was used to analyze seagrass depth distribution and abundance, which we surveyed along water depth gradients and shoreline orientation. Other pertinent water quality parameters - turbidity, [chlorophyll a], dissolved color, dissolved oxygen, pH, salinity, temperature, sediment, nutrients, and water level were monitored in-situ or obtained from the NERR monitoring data. The coverage and distribution of the beds dominated by R. maritima and the Ruppia—Halodule mixed beds of the tidal bay area (the estuarine area) in the reserve vary substantially primarily due to changes in R. maritima abundance between summer and fall. Our results on site variation in SAV coverage suggest that shore orientation and wind-driven energy within the estuarine system might be contributing factors to the spatial difference in the shallow estuary. The estuarine Ruppia population that grows in the shallow, high wave energy environment has an annual growth pattern: seedling growth in early spring, rapid vertical growth in April, producing abundant inflorescence and seeds in May and June, and senescence in the fall. On the other hand, R. maritima that occurs in the bayous and marsh in the reserve area, where tides and wind-driven wave actions are less severe, rarely flowers and sets seeds. Our results also suggest that consistent SAV survey efforts are needed to reduce errors in assessments of disturbance/restoration impacts and long-term trend, which will provide a useful tool for management and research.

Influences of Land Surface Characteristics on Precipitation over the Lower Mississippi River Alluvial Plain

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Dyer J.

The lower Mississippi River alluvial valley, covering sections of Mississippi, Arkansas, and Louisiana, is well recognized as a major agricultural center of the US. The region is characterized by extremely fertile soils deposited through repeated flooding of the Mississippi River; therefore, a large portion of the area is cultivated. Since roughly 1940, land use, vegetation, and soil characteristics have remained relatively consistent over the area, with irrigation levels increasing in association with crop density. Research has shown that agriculture can have an influence on regional weather variability through land use, soil type, and vegetation patterns by influencing energy and moisture transport into the atmospheric boundary layer. Due to the relatively sharp contrasts in these surface characteristics between the alluvial valley and surrounding regions, it is suspected that anthropogenic weather modification may be occurring in the form of enhanced mesoscale convective circulations. These circulations are most evident during the warm season when radiational surface heating is greatest and synoptic-scale forcings are minimal, and can have a direct influence on agriculture by varying the intensity and distribution of convective precipitation. The purpose of this project is to define and quantify the location and intensity of convective boundaries and associated precipitation over the lower Mississippi River alluvial valley. This will aid water resource managers and meteorological forecasters in recognizing the relative climatological patterns of rainfall during the growing season, and will provide information on the influence of anthropogenic land use and soil moisture boundaries on precipitation distribution. Initial results from the study indicate an eastward shift in warm-season precipitation relative to predominantly agricultural areas, such that rainfall is minimized over the lower Mississippi River alluvial valley and maximized directly eastward along the Hwy. 45 corridor. Although there are a number of factors that combine to generate this pattern, it is expected that enhanced soil moisture and latent heat flux due to heavy irrigation over the alluvial plain may play an important role in generating more intense convective boundaries over the region, leading to increased downstream transport of atmospheric moisture and subsequent precipitation.

Simulated Solute Transport and Shallow Subsurface Flow in Northwestern Mississippi

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Rose C.E., Nimmo J.R., Perkins K.S., Coupe R.H.

Solute transport and subsurface flow through a Sharkey Clay soil typical of a soybean field in the alluvial plain of northwestern Mississippi were simulated using the two-dimensional, variably-saturated flow model of solute transport (VS2DTI) developed by the U.S. Geological Survey. The model was developed and validated using data collected from a 2-m ring infiltration test, which include: calcium bromide (CaBr) concentrations at depth, water flux, and soil moisture content. Local and State agencies are attempting to develop a plan for sustainable use of the Mississippi River Valley alluvial aquifer, which is heavily pumped for irrigation and has documented water-level declines of tens of feet in some areas over time. A critical component to determining the sustainable yield of the aquifer is recharge, both the amount and source. The most recent groundwater model simulation by the U.S. Geological Survey in 2001 estimated that about 5 percent of precipitation recharges the alluvial aquifer annually; more localized studies found that number is as high as 17 percent. Due to the complexity of recharge processes, a tool for local estimation of recharge is necessary. In this study, simulated results, using VS2DTI, were compared to observed infiltration rates along with flow direction and extent of the CaBr tracer. Observed tracer concentrations and flow were found to be more spatially variable than simulated solute transport and subsurface flow. This suggests flow in the vadose zone is not only dependent on the medium of soil and its physical properties, but also on anisotropic anomalies, such as capillary or layer barriers, or mudcracks and large organic particles, which can produce preferential flow pathways.

Protecting Water Quality in Your Community

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Roberts C.D.

Most of us would prefer to ignore sewage. Rarely do we discuss what happens to water after it exits our homes through toilets, sinks, and showers. Yet, it has important ramifications for the rivers and streams that we love. Fresh, clean water is a human right and serves as the lifeline of the earth’s ecosystems. Not only do we drink water, we use it for cooking, cleaning, recreation, fishing, transportation, and commerce. All those uses are jeopardized when surface water is polluted by sewage.

In order to help Gulf residents recognize and address sewage pollution problems in their streams, bayous, and lakes, the Gulf Restoration Network produced Our Water Our Health, A Citizen’s Guide to Sewage Pollution manual and training seminar. The basics of the training include sewage 101, documenting a problem, commenting on permits, how to run a public campaign for clean water, messaging techniques, how to set up a press conference, and many other skills and knowledge based modules. The manual reviews topics such as: how sewage treatment works, law and policy of wastewater, what types of pollution come from sewage treatment plants, how to identify problems in your local water supply, and the basics of how states grant permits to sewage treatment plants. After attending this training, participants will be able to successfully advocate for better wastewater treatment, utilizing tools such as coalition building, media, and the Clean Water Act!

The Mississippi Embayment Regional Aquifer Study (MERAS)—Model Construction, Simulation of Groundwater Flow, and Potential Uses of a Regional Fl

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Clark B.R., Hart R.M.

The U.S. Geological Survey (USGS) Groundwater Resources Program supports projects to determine groundwater availability in multiple areas across the United States. One project is the Mississippi Embayment Regional Aquifer Study (MERAS). The primary tool used to evaluate groundwater availability in the embayment is the MERAS groundwater flow model. The construction of the MERAS model, using the USGS MODFLOW-2005 modeling software, included 2,700 geophysical logs for hydrogeologic framework development; 137 years of groundwater withdrawal information; 70,000 groundwater withdrawal locations; 39 rivers comprising 6,900 river miles; and precipitation, land use, surficial geology, and aquifer properties covering 78,000 square miles. Model calibration data include 55,000 ground-water level observations and streamflows at 14 stream-gage locations.

The MERAS model simulates groundwater flow from 1870 to 2007 and has been used to project impacts of climate variability on groundwater flow to the year 2037. Values of root mean square error between simulated and observed hydraulic heads of all observations up to 2007 ranged from 12.23 ft in 1919 to 48.19 ft in 1951. The MERAS model has been used to simulate climatic effects on the groundwater flow system by changing precipitation and streamflow input values based on projections of historic climate data analysis. Preliminary results of the groundwater flow model indicate deepening cones of depression over the next 30 years in the Mississippi River Valley alluvial aquifer in the northern part of the embayment.

Local stakeholders may also benefit from the use of additional MODFLOW-2005 methods and processes in conjunction with the MERAS model; the Local Grid Refinement (LGR) method and the Groundwater Management (GWM) process can provide excellent information for the local water manager. Potential use of the LGR method allows for more finely discretized local-scale areas to be simulated within the embayment while using the MERAS model as a boundary which contributes or receives flow. The GWM process allows for the optimization of groundwater pumpage given constraints such as drawdown, water level, and streamflow. These types of analyses with LGR and GWM can be particularly useful in areas where intense pumping stresses the groundwater- surface water system by lowering groundwater levels, reducing base flow, and ultimately inducing leakage from surface water bodies to the groundwater system. In a broader sense, the GWM process might be used in a regional application to evaluate issues related to resource sustainability on an intrastate or interstate scale.

Water quality in the Coldwater River Basin: Comparing traditional measures of water and habitat quality to index of biotic integrity findings.

Final Project Report, Project 2007MS62B

Year: 2009 Authors: Tietjen T., Ervin G.N.

The US Army Corps of Engineers in conjunction with the Mississippi Department of Environmental Quality has worked to determine the quality of water in the streams of the Mississippi Delta region using an Index of Biotic Integrity (lBI) approach. This approach to water quality monitoring seeks to use information extracted from fish community composition and habitat parameters to provide an integrated and comprehensive picture of water quality that is reported to be superior to traditional grab samples analyzed for chemical water quality parameters. We have been working to collect water samples from a subset of these sampling sites and analyzing this water using traditional measures of water quality. These samples have been analyzed for a variety of chemical (Nitrite+Nitrate-Nitrogen, Ammonium-Nitrogen, Soluble Reactive Phosphorus, Oxygen, pH), biological measures (Total Coliform bacteria, Fecal Coliform bacteria, Chemical Oxygen Demand), and physical measures (suspended sediments, temperature). We compared these data sets by examining correlations between IBI scores and quantitative measures ofwater quality. This approach did not help substantiate the value ofthe IBI approach or provide guidance for mitigation and restoration activities that likely would benefit these streams.

Multi-scale evaluation and analysis of precipitation patterns over the Mississippi Delta

Final Project Report, Project 2008MS73B

Year: 2009 Authors: Dyer J.

The Mississippi River floodplain in northwestern Mississippi, often referred to as the Mississippi Delta, is extremely important for regional economic stability and growth due to the widespread agriculture in the area. The region is unique in that there are currently three sources of precipitation measurements available: (l) radar-derived precipitation estimates from National Weather Service (NWS) NEXRAD network, surface observations from NWS recording stations, and surface observations from US Department of Agriculture (USDA) Soil Climate Analysis Network (SCAN) recording stations. In terms of water resource management and climatological precipitation research, quantitatively defining the biases associated with available precipitation data sources is critical in choosing which source to use for a given application. Additionally, due to the importance of precipitation in agriculture along with recent drought in the Mississippi Delta region, precipitation patterns should be reevaluated in terms of duration frequency, and extent. The inclusion of long-term data from surface gages along with shorter-term but higher resolution radar-derived rainfall estimates allow for a detailed analysis of past and current precipitation trends. This will lead to a better understanding of rainfall trends and patterns and potentially better prediction of future rainfall.

A continuation of climatological and cultural influences on annual groundwater decline in the Mississippi Delta shallow alluvial aquifer: Modeling p

Final Project Report, Project 2008MS72B

Year: 2009 Authors: Wax C.L., Pote J., Massey J.

Water use from the delta aquiter, contributed as in-kind contribution to the project by the Yazoo-Mississippi Delta Joint Water Management District, has been quantified by crop, acreage, and irrigation method. A relationship between growing season rainfall and irrigation water use has been developed to link interannual variations in water use to variations in climate (rainfall). Water use coefficients have been developed to link each specific type of irrigation on each crop type with a water use amount in acre feet per acre. A complete prototype water use model has been completed using acreages, irrigation methods, and management strategies in place during 2006 in Sunflower County to predict annual water demand for cotton, rice, soybeans, corn, and catfish. Figure 1 shows the inputs and the resulting estimate of annual water use for Sunflower County. The model is constructed in an Excel spreadsheet. The interactive model file is sent as a separate file along with this report.

Water Quality Trading: Is it Realistic for the Mississippi River?

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Showalter S.

Although significant progress has been made since passage of the Clean Water Act in 1972, the stated Congressional goal of assuring that all waters are "fishable/swimmable" remains elusive. Traditional "end-of-pipe"pollution-control measures must be supplemented with new policies to diffuse sources of pollution such as stormwater and agricultural runoff. One such innovative policy is water quality trading. In December 2006, the State of Pennsylvania joined ten states that currently have some form of a water quality trading program by approving a state administrative policy to allow point sources to offset pollution discharges by purchasing "credits" from other facilities or farmers. Similarly, in August 2008, the Florida Department of Environmental Protection proposed regulations to establish procedures for water quality trading, and. trading programs also are in development in Minnesota, West Virginia and Maryland. In selecting ten finalists for its "Targeted Watershed Grants" on water quality trading this past December, the U.S. Environmental Protection Agency (EPA) is encouraging states along the Mississippi River to consider implementing trading programs to address the hypoxia, or low oxygen levels, in the Gulf of Mexico. Nonetheless, the courts have not reached consensus on whether the Clean Water Act allows point sources to offset discharges into impaired waterbodies, or waters failing to meet state water quality standards. For example, in Friends of Pinto Creek v. EPA, 504 F.3d 1007 (9th Cir. 2007), the Ninth Circuit sided with an environmental group claiming that the EPA’s authorization of upstream remediation to offset a company’s copper discharges into the impaired Pinto Creek violated the Clean Water Act. This presentation will analyze the existing state water quality trading programs in light of the legal and scientific issues that may arise as states in the Mississippi River Basin consider implementing such programs.

Watershed Assessment and Education

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Silitonga M., Johnson A.

The Coles Creek Watershed, located in the southwestern quadrant of the state of Mississippi, is listed under the US EPA impaired water section 303(d). Degradation of the ponds/lakes and streams/creeks in this watershed is caused mostly by biological impairment, followed by nutrients, organic enrichment or Low Dissolved Oxygen, sediment/ siltation, pesticides, and pathogens (US EPA, 2007). Water samples will be collected from waterbodies in the Coles Creek watershed for physical, chemical, and biological analysis. Sampling will be conducted every month over a 12- month period to evaluate the spatial and temporal variability of water quality. Positions of sample locations will be geo-referenced to be displayed on a map using ArcView. In addition, soil and rainfall data will be used to study the correlation between land-use and water quality. The analysis of the results will help us to better understand the quality of water in the watershed. Results will also help us to determine the best alternative management practice(s) to be adopted and implemented in the community. Based on the results and findings, educational materials will be developed and disseminated to the communities. This effort will help increase the community awareness of their environment and encourage them to adopt and implement BMPs on their land which will lead to promoting environmental health and its sustainability, thereby, having good water quality to support the economic development in the area.

The Oklahoma Water Bank Project

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Hurt K.

The Arbuckle Simpson aquifer is located in south central Oklahoma. Although it is a highly productive karst aquifer that provides a crystal clear supply of groundwater to a multitude of springs and streams in the area, it has relatively limited storage. As such, frequent recharge events are necessary to maintain spring flows, base flows in area streams and water levels in area wells. Development of the local area and reliance on groundwater and spring water for municipal supplies has resulted in increased depletion rates during drought periods such as the extreme 2005 –2006 period. However, during 2007, the area experienced multiple flood events that caused millions of dollars of damage to homes, property and businesses.

This back to back occurrence of damaging droughts and floods set the stage for local leaders, scientists and regulators to write legislation supporting the Arbuckle Simpson Water Bank project. The project is designed to divert surface water captured by upstream flood control structures (i.e., NRCS watershed lakes) to the subsurface during flood events. This management approach allows the refilling of aquifers with damaging floodwater that downstream users do not desire. In a sense it turns flood lemons into drought lemonade. The partners on the project include the City of Ada, OK, the Chickasaw Nation, the Oklahoma State Climatologist, the Oklahoma Water Resources Board, the Oklahoma State Legislature, the National Weather Center, the National Severe Storms Lab, the Oklahoma Department of Environmental Quality, the Oklahoma Conservation Commission, the Bureau of Reclamation, University of Oklahoma and Oklahoma State University. The project was recently selected as the winner of the 2009 Secretary of the Interior’s "Partners in Conservation" award.

This presentation will include information on cutting edge technology used to predict, measure, manage and recharge water, including:

• Advanced radar systems,
• Mesonet meteorological stations,
• Passive filtration systems,
• Engineered recharge zones,
• Computer modeling of predicted water supply inventories,
• Web based information sharing.

Molecular Identification of Pentachlorophenol (PCP) Tolerant Bacterial Communities in Contaminated Groundwater

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Stokes C.E., Prewitt M.L., Borazjani H.

Pentachlorophenol (PCP), a highly toxic and recalcitrant wood preservative, contaminates groundwater aquifers in many areas of United States. Improper handling, storage, and disposal practices in the past have led to the contamination of groundwater at many wood treatment facilities. Biosparging, the injection of clean air and nutrients under pressure into the groundwater system, has emerged as a viable in-situ treatment option for removal of this type of contamination. Previous studies in this area have relied on growth media cultures for isolation and identification of the bacterial community that is responsible for the degradation of the pollutant. However, molecular identification of DNA extracted from the contaminated groundwater will provide a more accurate description of the microbial community. Seven biosparging wells located at a wood treatment facility with a PCP groundwater contamination in central Mississippi have been monitored since 2001. Groundwater samples from these existing wells were taken quarterly and examined for total PCP concentration. DNA was extracted from these water samples using a WaterMaster DNA purification kit. The 16s region from this DNA was also amplified using bacterial specific primers and then cloned into E. coli cells. Cloned E. coli cells were extracted and sequenced for identification. The goals of this research were to identify the most PCP-tolerant bacterial communities and to determine the PCP tolerance limits of these bacterial communities.

Composition and Size Distribution of Colored Dissolved Organic Matter in River Waters as Characterized Using Fluorescence EEM and Flow Field-Flow Frac

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Zhou Z., Stolpe B., Guo L.

Colored dissolved organic matter (CDOM) is an active organic component in natural waters, and can have an effect on environmental and water quality in aquatic systems. In order to examine the composition and size-distribution of CDOM in the Mississippi and Pearl rivers and the effect of flooding, monthly water samples and flood samples were collected from the lower Mississippi River at Baton Rouge and the Pearl River at Stennis Space Center, followed by size fractionation using ultrafiltration and flow field-flow fractionation (FlFFF) and measurements of dissolved organic carbon (DOC), specific UV absorbance (SUVA) and fluorescence excitation emission matrix (EEM). Concentration of DOC varied from 2.8 to 3.9 mg-C/L in the Mississippi River, but was much higher in the Pearl River, ranging from 3.9 mg-C/L in Mar-2009 to 13.6 mg-C/L during the Apr-2009 flood event. Average value of SUVA (254 nm) was 0.035±0.003 L/mg-C/cm in the Mississippi River and 0.045±0.006 in the Pearl River. In the Mississippi River the SUVA₂₅₄ was fairly constant, indicating similar DOM sources between seasons, while the SUVA₂₅₄ in the Pearl River varied with DOC concentration and discharge, indicating variable DOM composition. Colloidal organic matter (1-450 nm) from the Pearl River had a SUVA₂₅₄ value of 0.889 compared to 0.0029 for the <1 nm dissolved fraction, showing that CDOM is mostly present in the colloidal fraction and enriched in microbially-derived humic substances (SUVA at 370 nm). The colloidal size spectra of CDOM determined by FlFF with UV absorbance detection show that the majority of CDOM is found in a population of small (1-4 nm hydrodynamic diameter) colloids in both rivers although the relative proportions of CDOM in the range of 1- 4 nm, 4-20 nm, and >20 nm varied between samples. Fluorescence index (FI), which is the ratio of the emission intensity at 450 nm to that at 500 nm under excitation of 370 nm, shows a more terrestrially derived CDOM in the Pearl River (1.29-1.36), but more microbially derived CDOM in the Mississippi River (1.47-1.49). Based on the integration of fluorescence intensity in the FlFFF fractograms, the ratio of DOC-normalized protein-type fluorophores (Ex/Em 276/340 nm) (proFL/DOC) and humic-type fluorophores (Ex/Em 350/450 nm) (humFL/DOC) exhibits more amino-acids and humic-substance components of CDOM in the Pearl River (7.7-16 and 1.0-3.6) than in the Mississippi River (6.5-9.4 and 0.2-1.3). Moreover, the humFL/DOC value during flooding in the Pearl River was three times higher than normal sample values, suggesting more humic substances during the flooding event. In the EEM measurements, the Ex/Em wavelength at maximum fluorescence intensity shifted from 330/445 nm in normal samples to 338/451nm in flood samples, suggesting an increased input of humic substances that are less transformed by photochemical or microbial processes during the flooding event in the Pearl River. The SUVA and fluorescence EEM coupled with FlFFF and ultrafiltration can be used to effectively investigate the source and composition of CDOM in natural waters.

Ground Water-Surface Water Interaction in the West-Central Delta (Washington County)

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Parrish P.C.

From the end of the 2008 irrigation season to the beginning of the 2009 irrigation season, measurements were made at eleven Mississippi Delta irrigation wells. The measurements were made along a profile in Washington County. This profile extended from the Longview community to just west of Hollandale, MS. All of the wells lie on a general West to East trend.

The purpose of this study was to evaluate the interaction between surface water of the Mississippi River and ground water of the Mississippi River Valley Alluvial Aquifer (MRVA) along a specific profile. The study also allowed for pinpointing of the localized ground water divide. Data from 2008-2009 was then compared to data from a 1992-1993 study along the same profile. The question that must be asked is whether the ground water divide and the Mississippi River’s influence shifted over the last 15-16 years. If the answer is yes, then more study will be needed to determine if this is localized and to determine what factors may have contributed to the shift.

Development of Water Correction Algorithm for Underwater Vegetation Signals

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Cho H.J., Lu D., Washington M.

The unique spectral characteristics of green vegetation, low reflectance in red and high reflectance in Near-Infrared (NIR), have been used to develop vegetation indices, such as Normalized Difference Vegetation Index (NDVI). Our preliminary studies suggest that NDVI was not a useful indicator for submerged aquatic vegetation (SAV), even in clear water, due to energy absorption by water in the NIR region. In order to improve the use of the vegetation indices, we modeled the depth-induced water absorption and scattering through a controlled indoor experiment. We used a GER 1500 spectroradiometer to collect spectral data over an experimental water tank (70cm tall, 50cm wide) that was deployed with a black panel or a white panel at a time; the panels were cut to fit the bottom of the tank. Our assumptions were: (1) the black bottom panel absorbs 100% incoming light; (2) the white bottom panel reflects 100% incoming light; and (3) the water volume scattering and absorption remains the same for the two conditions (black and white bottoms) at a given depth. The measured upwelling radiance was converted to % reflectance. We developed correctional algorithms for water scattering and absorption using the reflectance data. After finding the contribution of these features, we were able to remove the water effects from the measured data. The SAV reflectance that was corrected using the algorithm produced a spectral signature more closely resembling those of terrestrial vegetation. The application of the algorithm significantly improved the vegetation signals, especially in the NIR region. Our results suggest the conventional NDVI: (1) is not a good indicator for submerged plants even at shallow waters (0.3 m); and (2) the index values can significantly improve once the water effects are modeled and removed.

Sequence Stratigraphy, Depositional Systems and Ground-Water Supply

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Dockery III D.T.

Ground-water supplies in the state’s Tertiary, Late Cretaceous, and even Paleozoic aquifers are not all evenly distributed. Many (and some of the most prolific) are concentrated in valley-fill deposits created during times of low sea level and in the channels of fluvial and deltaic systems that formed during sea-level lowstands and sea-level highstand-regressive intervals. Examples of such linear and lenticular water-supply sands include: (1) valley-fill sands in the Tuscaloosa Formation, (2) valley-fill sands in the basal Clayton Formation, (3) valley-fill sands in the Coal Bluff Member of the Naheola Formation (lower Wilcox aquifer), (4) valley fill sands in the Gravel Creek Sand Member of the Nanafalia Formation (lower Wilcox aquifer), (5) valley-fill sands in the basal Tuscahoma Formation (middle Wilcox aquifer), (6) highstand-regressive channel sands in the lower Hatchetigbee Formation (upper Wilcox aquifer), (7) valley-fill sands in the Meridian Sand (upper Wilcox aquifer), (8) highstand-regressive channel sands in the Kosciusko Formation (Sparta Aquifer), (9) highstand-regressive channel sands in the Cockfield Formation, (10) valley-fill sands in the Forest Hill Formation, (10) valley-fill sands in the Waynesboro Sand, (11) valley fill sands in the basal Catahoula Formation, (12) valley-fill sands in the Citronelle Formation and other high-level terrace deposits, and (13) valley-fill sands in the Mississippi River Alluvium (Alluvial aquifer).

There are two major drainage systems responsible for most of the valley-fill and fluvial/deltaic-channel deposits, which serve as aquifers for ground-water supplies in Mississippi. The first is an ancient drainage basin with an Appalachian source, which is often referred to as the ancestral Tennessee River. This ancient river system is responsible for valley-fill gravels and sands of the Tuscaloosa Formation in northeastern Mississippi and for the vein-quartz and heavy minerals in the state’s Tertiary and Quaternary gravels and sands. The second drainage basin drained a portion of the North American mid-continent and is referred to as the ancestral Mississippi River. This river system has been credited for fluvial sands as old as the Late Jurassic sandstones in the Smackover Formation in west-central Mississippi. It is certainly responsible for those Late Cretaceous and Tertiary formations that thicken along the axis of the Mississippi Embayment as well as the Pliocene gravels of the Citronelle Formation in west-central Mississippi and the perched Early Pleistocene pre-loess gravel deposits below the loess along the eastern Mississippi River valley wall, extending from Tennessee to Louisiana.

Monitoring and Statistical Analysis of Fecal Indicator Bacteria in Lower Sardis Lake, Mississippi

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Surbeck C.

The quality of a recreational water body is usually assessed by quantifying fecal indicator bacteria (FIB) in the water. FIB are groups of bacteria that together may indicate the presence of pathogens and have been strongly correlated with diseases contracted by swimmers in recreational waters. A two-week monitoring event was conducted in the summer of 2008 at 10 locations in the Lower Sardis Lake in northern Mississippi. Samples at selected beaches and embayments were collected and analyzed for total coliforms, E. coli, temperature, dissolved oxygen, nitrate, phosphate, and phenols. Concentrations of the FIB E. coli were generally below the U.S. Environmental Protection Agency (EPA) criterion of 126 per 100 mL for swimming freshwaters, which is consistent with previous research that attributes high FIB concentrations to large urban centers and not rural areas, such as the field location of this study. However, higher concentrations than the EPA criterion were found in lake water near a residential area and at an embayment with presence of wildlife. Further, results from creek sampling at a nearby town indicate consistently high E. coli concentrations at a geometric mean of 424 per 100 mL. Given the incidences of higher than standard FIB concentrations, statistical analyses were conducted to relate FIB concentrations to days of high-swimmer visits, presence of nutrients, and location.

Anthropogenic Chemicals in the Source and Finished Water From Three Mississippi Communities That Use Surface Water as Their Drinking-Water Supply

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Rose C.E., Coupe R.H., Smith C.M.

The U.S. Geological Survey, in cooperation with the Mississippi Department of Environmental Quality, began a sampling program in the fall of 2007 to analyze water samples for a suite of wastewater indicator compounds and pesticides for the three drinking-water facilities in Mississippi that use surface water from the Pearl, Tombigbee, and Tennessee Rivers as their source water. Three samples, from both source water and finished water, were collected from each facility in October 2007, and January and May 2008. Few wastewater indicator chemicals were detected in source water; however, low concentrations of some commonly used herbicides were detected in the source and finished water from all three facilities. None of these compounds were detected in finished water at or above established drinking-water standards. Modern society depends upon chemicals to prevent and combat disease, cleanse and soften skin, smell better, reduce wrinkles, influence moods, and control weeds and insects for safety and aesthetic reasons. These compounds, which can be found in any drug or hardware store, enter the environment through runoff from agricultural fields, urban lawns, highway rights of way, parks and recreational areas, domestic sewage, and other sources. Some of these compounds have been shown to be stable in the environment, and also have been shown to survive the conventional drinking-water treatment process and be detected in the finished drinking-water supply. Little is known about the abundance and persistence of these compounds in surface waters of Mississippi; hence, there is little information on what effect further development in basins upstream of source-water intakes will have on downstream communities that rely on surface water as their source for drinking water.

The Use of Microcosm Studies to Determine the Effect of Sediments and Nutrients on Fecal Indicator Bacteria in Lake Water

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Kinnaman A., Surbeck C.Q.

Field and laboratory experiments were conducted to determine the effects of sediments and nutrients on the persistence of the fecal indicator bacteria (FIB) groups total coliforms and Escherichia coli (E. coli) in lake water using samples collected in the field and laboratory-based microcosms. Samples were collected at a discharge point of Thompson Creek into Lower Sardis Lake in northern Mississippi. Samples were tested for total coliforms, E. coli, dissolved oxygen, temperature, dissolved organic carbon, nitrate, phosphate, and phenols. Following initial sample testing, seven microcosms were created in the laboratory: (1) lake water, (2) lake water and sediment, (3) lake water and sterilized sediment, (4) sterilized lake water and sediment, (5) sterilized deionized water and sediment, (6) sterilized lake water (control),and (7) sterilized deionized water and sterilized sediment (control). Each microcosm had a function to test a different hypothesis related to whether sediment affected FIB concentrations in water and vice-versa. Samples from each microcosm were collected approximately every 12 hours for two days and 24 hours for the subsequent five days. FIB concentrations from the microcosms were plotted against time, and first-order decay constants were obtained. In addition, correlations were run between FIB decay constants and water quality parameters to assess the dependence of FIB die-off on nutrients. Preliminary results show that FIB decay rates were lower when sediment was present and that high dissolved organic carbon concentrations were associated with a temporary increase in FIB concentrations. The data found on die-off rates and on FIB dependence on nutrients is useful to determine parameters for numerical modeling in lakes.

Drinking Water Systems in Mississippi: Public Owned or Government Owned?

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Barrett J.

Mississippi (MS) contains approximately 1300 water systems (system). Currently, there has been no issue raised in an effort to make systems more efficient or more economical for the customers. Also, there has been no effort to determine if a system is efficient or economical. The Mississippi State Department of Health (MSDH) completes a capacity development assessment annually for every system and the scores encompass technical, managerial, and financial, ranging in value from 0 (zero/worst) to 5 (five/best). Approximately forty percent of systems with a population below 501 consistently score below 3.0 on the capacity assessment. There are contradictory mindsets in MS as to the future direction of systems: (1) all systems should take whatever actions possible to provide safe drinking water to their customers at an affordable price and (2) this water system has been in my family for generations or this water system holds this community together. I will use the MSDH assessment scores to view the viability of specific systems by population ranges. This will set a basis to current status and possible future action in relation to systems by asking: does the system remain apathetic and ask for assistance once the system is in disrepair, does the state of MS take over, or will water related agencies promote continuing education in an effort for the systems to increase viability themselves. With each of these three options, I will look at the agencies and individuals involved and delineate how they will be affected and why it matters to them. The results should show how economies of scale affect systems in the matter that smaller systems tend not to be as economical or efficient for its customers.

Laboratory-Scale Treatment of CCA-Contaminated Wood Waste

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Bricka R.M., Broussard J.

Since the early 1970’s, the most widely used preservative in the wood preservation industry has been chromated copper arsenate (CCA) treatment. Current estimations suggest that there may be as much as 240 million tons of CCA wood waste available for Disposal by the year 2020.

Until recently, landfilling the out of service materials was a generally accepted method of disposal. Recently, problems with soil and groundwater contamination have arisen, and the role of CCA impregnated wood waste in the matter has been confirmed. As a result, the need for an efficient and effective method of heavy metal separation form wood waste has become eminent.

In this research, electrokinetic treatment of CCA impregnated wood fines was examined. Out of service CCA wood waste was subjected to electrokinetic treatment in a batch reactor under pH controlled conditions. The ionic nature of the metal oxides contained in the CCA impregnated wood will allow for the metals to be mobilized and metal concentrations are expected to decrease in the waste wood while increasing the proximity of the electrodes. In addition to this base case study, chemical extractions with electrode amendments were examined under controlled conditions before they were subjected to electrokinetic treatment, and final overall metal removal. Mass balances were performed using ICP-AES equipment. In the extended research plan, the more effective reactions sequences will be subjected to further testing where the roles of independent variables such as reactor solution pH, particle size, current density, Oxidation/Reduction potential, and treatment time will be examined. The ultimate goal of this research will be to evaluate the feasibly of Electrokinetic pretreatment for CCA impregnated wood.

Oceanic-Atmospheric Modes of Variability and Their Effects on River Flow in the North Central Gulf of Mexico

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Sanchez-Rubio G., Perry H.M., Biesio P.M.

The present study examined the individual and combined influences of four oceanic-atmospheric modes of variability on Mississippi River and Pascagoula River flows. Mississippi River and Pascagoula River mean flows, within long-term climatic phases, were compared using a parametric t-test. While the combination of Pacific Decadal Oscillation (PDO), Atlantic Multidecadal Oscillation (AMO), and North Atlantic Oscillation (NAO) phases determined long-term Mississippi River regimes, the coupling of AMO and NAO phases determined long-lasting Pascagoula River flow regimes. Mississippi River mean flow was higher during the PDO warm (PDOw), AMO cold (AMOc), and NAO positive (NAOp) phases than during the PDO cold (PDOc), AMO warm (AMOw), and NAO negative (NAOn) phases. Pascagoula River mean flow was higher during AMOc and NAOp phases than during AMOw and NAOn phases. During a long-term drought regime in the Pascagoula River basin, interannual fluctuations in the Pascagoula River flow were associated with the El Niñ o Southern Oscillation (ENSO) events. During the AMOw/NAOn phase, Pascagoula River flow showed a significantly steady reduction from ENSO warm to ENSO neutral to ENSO cold events. In the northcentral Gulf of Mexico, more than 90% of the freshwater is discharged by the highly correlated Mississippi, Atchafalaya, Pascagoula, and Pearl Rivers. Climate-related hydrological regimes have been associated with fisheries resources availability and the economic and social wealth of coastal communities.

Modeling Fluid Mud

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Hall C.L.

Fluid mud is defined as a high concentration aqueous suspension of fine-grained sediment in which settling is substantially hindered. Fluid mud occurs in many ports and channels around the world. It can severely affect navigation due to the sharp increase in sediment concentration returning a false bottom to sonar systems, and the fluid mud can fill in channels faster than it can be dredged, restricting port access. Fluid mud can also suffocate benthic organisms or contribute to eutrophication. This study is designed to further advance the field of fluid mud modeling to aid in the prediction of fluid mud formation and movement. Most available hydrodynamic models do not include a fluid mud routine. The addition of fluid mud equations to these existing models could greatly enhance sediment process modeling in areas that experience fluid mud. These equations calculate formation, dissipation, flow, and consolidation to adequately describe the physical processes affecting fluid mud. Modeling results using these equations compared with field data as well as laboratory experiments will determine their usefulness. Laboratory experiments include measuring the flow of fluid mud under shear stress and on a slope. With accurate prediction of the physical processes governing fluid mud, dredging alternatives could be developed to reduce dredging requirements and improve port access.

Occurrence of Nitrate in the Mississippi River Valley Alluvial Aquifer at a Site in Bolivar County, Mississippi

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Welch H.L., Coupe R.H., Green C.T.

Annually in the United States, about 12 million tons of nitrogen are applied as commercial fertilizer causing contamination of surface and groundwater resources. In the Mississippi Delta, large amounts of agricultural chemicals are applied to crops on an annual basis, but are rarely detected in groundwater. Previous studies have indicated that the shallow alluvial aquifer in the Delta is unaffected by anthropogenic activities at the surface because of an overlying impervious clay layer. However, model simulations have indicated that the alluvial aquifer is recharged by a small percentage (5%) of rainfall. In 2005, the U.S. Geological Survey National Water-Quality Assessment (NAWQA) Program began a study in the Bogue Phalia basin to assess how environmental factors and agricultural practices affect the source and transport of agricultural chemicals. Two wells located in a cotton field (surveyed as very fine sandy loam and silty clay) in Bolivar County, Mississippi were sampled for inorganic compounds, nutrients, and field parameters from June 2006 to November 2008. Nitrate was detected at concentrations ranging from 7.2 to 13 mg/L in a shallow well screened near the water table from 27 to 32 feet, but was not detected in a deeper well screened from 70 to 120 feet located approximately one-quarter mile from the shallow well. In June 2008, depth interval sampling was conducted in test holes drilled adjacent to the shallow well to better define the occurrence of nitrate at five depths ranging from 32.5 to 60 feet–between the depths of the shallow and deep wells. Nitrate concentrations decreased with depth in the water column, and there were no detections below a depth of 36 feet. Data indicate that some nitrate is being transported through the unsaturated zone into the alluvial aquifer, but it is being converted fairly quickly into ammonia and nitrogen gas under strong, reducing conditions in the aquifer. The data imply that the aquifer may not be as invulnerable to anthropogenic activities as previously thought.

Exploring Biologically Relevant Buffer Zones for Aquatic and Wetland Ecosystems in Northern Mississippi

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Ervin G.N.

Intact natural buffers surrounding streams and wetlands can reduce nutrient runoff into the water column, reduce sedimentation, and maintain or enhance general habitat quality for wildlife. However, a major obstacle in efforts at water quality improvement relates to the appropriate definition of what constitutes a sufficient buffer, in terms of buffer width or type of land cover within the buffer. The present studies evaluated patterns of correlation between land cover and wetland vegetation or aquatic biota to investigate optimal buffer widths associated with ecological integrity of inland freshwater streams and wetlands in northern Mississippi. Results indicated that the presence of a forested buffer (i.e., natural forest, silvicultural plantings, or a combination) of 70 to 100m in width was associated with an increase in ecological quality. Here, quality was represented as either the presence of species of high ecological conservation value, presence of plant species adapted to wetland conditions, or the absence of non-native plant species. On the other hand, landscape-scale disturbances were correlated with decreased ecological quality. For example, at proximities of 50m and beyond, there was a consistent association of agricultural land cover with the presence of non-native plant species in northern Mississippi wetlands. The conclusion is that intact, undisturbed buffers help to minimize negative impacts of land use on wetland and aquatic assemblages in the study area, but biological evidence of human activities remains, even where buffers are present.

Flooding or Precipitation: What is the Dominant Source of Moisture Sustaining a Backwater Bottomland Hardwood Forest?

Proceedings of the 39th Annual Mississippi Water Resources Conference

Year: 2009 Authors: Johnson D.R.

When modeling the potential impact of the Yazoo Backwater Pump Project on the Bottomland Hardwood Wetlands, the Corps assumed the precipitation played an insignificant role in the sustenance of these wetlands. That assumption will be examined through the use of a water budget equation and groundwater monitoring wells.

The dominant water demand in forested areas is from evapotranspiration. It is generally presented that a forested area will be a wetland if precipitation exceeds evapotranspiration. A wetland water budget is actually much more complicated than that. Forested wetlands have four potential sources of moisture: precipitation, surface water, groundwater, and tidal, and four potential methods to lose water: evapotranspiration, surface runoff, infiltration into groundwater and tidal. Yazoo Basin wetlands are not affected by tides and are disconnected from the alluvial aquifer by a confining clay layer. Thus there are only two remaining sources of moisture: precipitation and surface water (riverine flooding). This presentation will compare the relative roles of these two sources of moisture to the forested wetlands in the Yazoo Backwater Area.