This thesis examines the history of groundwater management through the development of groundwater conservation districts in Texas. Political, economic, ideological, and scientific understandings of groundwater and its regulation varied across the state, as did the natural resource types and quantities, which created a diverse and complicated position for lawmakers and landowners. Groundwater was consistently interpreted as a private property right and case law protected unrestricted use for the majority of the twentieth-century even as groundwater resources crossed property and political boundaries, and water tables declined particularly during the second-half of the century. The case study of the Brazos Valley Groundwater Conservation District describes the complicated history of groundwater in Texas as the state attempted to balance natural resource legislation and private property rights and illuminate groundwater’s importance for the future.

Management of groundwater as a common pool resource relies heavily on an institutional design that is fitted to the aquifers to be managed and is scaled to provide efficient and effective governance. Texas has committed to a decentralized system of groundwater management through Groundwater Conservation Districts (GCDs) that offers a high level of local control and area-specific adaptability. However, increasing pressures on the state’s groundwater resources coupled with a strong local aversion to outsider interference has resulted in a proliferation of small single-county GCDs that are neither well fitted to the aquifer systems nor sufficiently scaled to be efficient or effective. In recognition of these challenges, the persistent response has been a slow transition towards larger-scale management. Although a full transition to centralization via state control is not likely to be politically feasible, it would also be limited in its effectiveness, recognizing the wide diversity of climate conditions, water use patterns, growth projections, and aquifer characteristics that exist across the state. Regionalization is offered as a policy proposal for an institutional arrangement and scale of groundwater governance that provides a balance between centralization and decentralization, using institutions that are better fitted to the aquifer systems and appropriately scaled to provide sufficient funding and resources. The merits and logic of regionalized groundwater management have been recognized as demonstrated by the establishment of the joint regional-planning process within aquifer-based Groundwater Management Areas (GMAs), using GCD representatives as the de facto regional groundwater planners. However, the new unfunded mandates for which the already underfunded GCDs are now responsible and the extraordinary planning process complexity that has developed may prove to be unworkable. This realization compels consideration of management through regional authorities designed using the ready-made framework of the GMAs and principles gleaned from successful models of regionalization from other states and within Texas. Such regional authorities, if provided with sufficient resources and authority, would respect the logic of fit and scale and would be better equipped to address the current and future groundwater management challenges in Texas. / text

Ninety-eight percent of water taken from the Mississippi River Shallow Alluvial Aquifer, hereafter referred to as “the aquifer” or “MRVA,” is used by the agricultural industry for irrigation. Mississippi Delta agriculture is increasingly using more water from the MRVA and the aquifer has been losing about 300,000 acreeet per year. This research expands on previous work in which a model was developed that simulates the effects of climatic variability, crop acreage changes, and specific irrigation methods on consequent variations in the water volume of the MRVA. This study corrects an identified problem by replacing total growing season precipitation with an irrigation demand driver based on evaporation and crop coefficients and changing the time scale from the entire growing season to a daily resolution. The calculated irrigation demand, as a climatological driver for the model, captures effective precipitation more precisely than the initial growing season precipitation driver. Predictive equations resulting from regression analyses of measured versus calculated irrigation water use showed R2 and correlations of 0.33 and 0.57, 0.77 and 0.88, 0.71 and 0.84, and 0.68 and 0.82 for cotton, corn, soybeans and rice, respectively. Ninetyive percent of the predicted values fall within a range of + or - about 23,000 acreeet, an error of about 10-percent. The study also adds an additional conservation strategy through the use of surface water from onarm reservoirs in lieu of groundwater. Analyses show that climate could provide the entire water need of the plants in 70-percent of the years for corn, 65-percent of the years for soybeans and cotton, and even 5-percent of the years for rice. Storing precipitation in onarm structures is an effective way to reduce reliance of Delta producers on groundwater. If producers adopted, at a minimum, the 97.5:2.5 ratio suggested management practice, this minimal management strategy could potentially conserve 48-percent, 35-percent and 42-percent of groundwater for cotton, corn and soybeans, respectively. Even in extreme drought years such as 2007, cotton, corn and soybeans produced under the 97.5:2.5 management strategy could conserve 32-percent, 46-percent and 38-percent of groundwater, respectively.

With increasing population comes the concern for waste disposal. The absence of sanitary disposal methods has left most city residents with open landfills as their only source of waste disposal. The resulting leachate formed from the decomposition of these waste materials is highly polluting and finds its way to the underground water supply. The study investigated the effects of open landfill sites on the underground water quality by examining the physical and chemical properties of underground water in hand-dug wells around the Solous landfill sites in Igando, Alimosho Local Government Area of Lagos State. Solous landfill is the second largest landfill by landmass and volume of waste in Lagos State. Systematic random sampling was used for data gathering. Eighteen hand-dug wells were sampled at increasing distances from the landfill site. Physical, chemical and microbiological parameters were analysed at the Lagos State Environmental Protection Agency (LASEPA). Soil samples were also taken from both the A (0 – 30cm) and B (30 – 60cm) horizons of the water sampling points to determine the soil texture (silt, clay and loamy composition) and to show the impact of soil texture on ground water quality within the sampled area. The level of contamination of groundwater was also determined using the Contamination Index method. The results showed high degree of conformance with W.H.O standard with respect to the microbiological properties of the sampled groundwater. However, coliform tests indicated the potential presence of pathogens. Of the seven (7) physical parameters tested, conductivity was higher in one sample. The study of chemical properties from the eighteen wells showed five (5) parameters (dissolved oxygen, total alkalinity, iron, lead, nitrates and copper) above W.H.O limits in some samples. The water may therefore not be safe for human consumption and there is a serious need to monitor the groundwater quality in the area. The level of contamination of groundwater was also determined using the Contamination Index method. Areas of high and medium contamination were discovered. There was no area with low contamination level in the area sampled. Contamination levels were mapped to show the exact levels of contamination in the study area. The results of the soil analysis showed that the study area had soil that was mostly sandy in nature which may suggest an increase in parameters over time with significant health implications for the people who depend on surrounding wells for domestic use. The study also showed no significant variation in water quality with increasing distance from the dump site. Findings also indicated that the water around Solous 1 was of better quality for domestic use than groundwater around Solous 2 and 3 due to temporal reduction of contaminant concentration. There is therefore a need for adequate and proper planning, design and construction, and strategic management disposal of waste, as well as the implementation of a better sustainable environmental sanitation practice. / Environmental Sciences / M. Sc. (Environmental Science)

With increasing population comes the concern for waste disposal. The absence of sanitary disposal methods has left most city residents with open landfills as their only source of waste disposal. The resulting leachate formed from the decomposition of these waste materials is highly polluting and finds its way to the underground water supply. The study investigated the effects of open landfill sites on the underground water quality by examining the physical and chemical properties of underground water in hand-dug wells around the Solous landfill sites in Igando, Alimosho Local Government Area of Lagos State. Solous landfill is the second largest landfill by landmass and volume of waste in Lagos State. Systematic random sampling was used for data gathering. Eighteen hand-dug wells were sampled at increasing distances from the landfill site. Physical, chemical and microbiological parameters were analysed at the Lagos State Environmental Protection Agency (LASEPA). Soil samples were also taken from both the A (0 – 30cm) and B (30 – 60cm) horizons of the water sampling points to determine the soil texture (silt, clay and loamy composition) and to show the impact of soil texture on ground water quality within the sampled area. The level of contamination of groundwater was also determined using the Contamination Index method. The results showed high degree of conformance with W.H.O standard with respect to the microbiological properties of the sampled groundwater. However, coliform tests indicated the potential presence of pathogens. Of the seven (7) physical parameters tested, conductivity was higher in one sample. The study of chemical properties from the eighteen wells showed five (5) parameters (dissolved oxygen, total alkalinity, iron, lead, nitrates and copper) above W.H.O limits in some samples. The water may therefore not be safe for human consumption and there is a serious need to monitor the groundwater quality in the area. The level of contamination of groundwater was also determined using the Contamination Index method. Areas of high and medium contamination were discovered. There was no area with low contamination level in the area sampled. Contamination levels were mapped to show the exact levels of contamination in the study area. The results of the soil analysis showed that the study area had soil that was mostly sandy in nature which may suggest an increase in parameters over time with significant health implications for the people who depend on surrounding wells for domestic use. The study also showed no significant variation in water quality with increasing distance from the dump site. Findings also indicated that the water around Solous 1 was of better quality for domestic use than groundwater around Solous 2 and 3 due to temporal reduction of contaminant concentration. There is therefore a need for adequate and proper planning, design and construction, and strategic management disposal of waste, as well as the implementation of a better sustainable environmental sanitation practice. / Environmental Sciences / M. Sc. (Environmental Science)