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Modeling Effects Of Climatological Variability And Management Practices On Conservation Of Groundwater From The Mississippi River Valley Shallow Alluvial Aquifer In The Mississippi Delta Region
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Book Synopsis Modeling Effects of Climatological Variability and Management Practices on Conservation of Groundwater from the Mississippi River Valley Shallow Alluvial Aquifer in the Mississippi Delta Region by :
Download or read book Modeling Effects of Climatological Variability and Management Practices on Conservation of Groundwater from the Mississippi River Valley Shallow Alluvial Aquifer in the Mississippi Delta Region written by and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: 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 acre-feet 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. Ninety-five percent of the predicted values fall within a range of + or - about 23,000 acre-feet, an error of about 10-percent. The study also adds an additional conservation strategy through the use of surface water from on-farm 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 on-farm 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.
Book Synopsis Development of an Interactive Model Predicting Climatological and Cultural Influences on Annual Groundwater Volume in the Mississippi Delta Shallow Alluvial Aquifer by : Tia Lení Merrell
Download or read book Development of an Interactive Model Predicting Climatological and Cultural Influences on Annual Groundwater Volume in the Mississippi Delta Shallow Alluvial Aquifer written by Tia Lení Merrell and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Water volume in the shallow alluvial aquifer in the Mississippi Delta region is subject to seasonal declines and annual fluctuations caused by both climatological variability 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, MS are used to evaluate the climate-groundwater interactions in the Mississippi Delta region. This research produced 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 is accounted for in the model by predicative equations that relate annual measured plant water use (irrigation) to growing season precipitation amounts. This derived relationship allows the application of a long-term climatological record to simulate the cumulative impact of climate on groundwater used for irrigation.
Book Synopsis DEVELOPMENT OF AN INTERACTIVE MODEL PREDICTING CLIMATOLOGICAL AND CULTURAL INFLUENCES ON ANNUAL GROUNDWATER VOLUME IN THE MISSISSIPPI DELTA SHALLOW ALLUVIAL AQUIFER. by :
Download or read book DEVELOPMENT OF AN INTERACTIVE MODEL PREDICTING CLIMATOLOGICAL AND CULTURAL INFLUENCES ON ANNUAL GROUNDWATER VOLUME IN THE MISSISSIPPI DELTA SHALLOW ALLUVIAL AQUIFER. written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Water volume in the shallow alluvial aquifer in the Mississippi Delta region is subject to seasonal declines and annual fluctuations caused by both climatological variability 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, MS are used to evaluate the climate-groundwater interactions in the Mississippi Delta region. This research produced 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 is accounted for in the model by predicative equations that relate annual measured plant water use (irrigation) to growing season precipitation amounts. This derived relationship allows the application of a long-term climatological record to simulate the cumulative impact of climate on groundwater used for irrigation.
Book Synopsis The Effect of Groundwater Withdrawals from the Mississippi River Valley Alluvial Aquifer on Water Quantity and Quality in the Mississippi Delta by : Jeannie R. B. Barlow
Download or read book The Effect of Groundwater Withdrawals from the Mississippi River Valley Alluvial Aquifer on Water Quantity and Quality in the Mississippi Delta written by Jeannie R. B. Barlow and published by . This book was released on 2013 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt: Watersheds within northwestern Mississippi, a productive agricultural region referred to as the Delta, were recently identified as contributors of total nitrogen and phosphorus fluxes to the Gulf of Mexico. Water withdrawals for irrigation in the Delta have altered flow paths between surface-water and groundwater systems, allowing for more surface-water losses to the underlying alluvial aquifer. In order to understand how to manage nitrogen in a watershed, it is necessary to identify and quantify hydrologic flow paths and biogeochemical conditions along these flow paths, which ultimately combine to determine transport and fate. In order to evaluate the extent and role of surface-water losses to the alluvial aquifer on the transport of nitrate, a two-dimensional groundwater/surface-water exchange model was developed for a site within the Delta. Results from this model determined that groundwater/surface-water exchange at the site occurred regularly and recharge was laterally extensive into the alluvial aquifer. Nitrate was consistently reported in surface-water samples (n= 52, median concentration = 39.8 micromole/L), although never detected in samples collected from instream or near stream piezometers )n=46). Coupled model and water-quality results support the case for denitrification/ nitrate loss from surface water moving through an anoxic streambed. At larger scale, recent results from two Spatially Referenced Regressions on Watershed attributes (SPARROW) models imply that nitrogen is transported relatively conservatively once it enters the main channel of the Big Sunflower River Basin, which contributes much of the water discharging from the Yazoo River Basin to the Mississippi River. Net loss of nitrogen was assessed by comparing total nitrogen data from Lagrangian sampling events to chloride, drainage area, and predicted total nitrogen flux results from the SPARROW models. Results indicated relatively conservative instream transport of nitrogen at the scale of the Big Sunflower River Basin; however, two potential nitrogen loss mechanisms were identified: (1) transport and transformation of nitrogen through the streambed, and (2) sequestration and transformation of nitrogen above the drainage control structures downstream of Anguilla.
Book Synopsis Summary of Results of an Investigation to Define the Geohydrology and Simulate the Effects of Large Ground-water Withdrawals on the Mississippi River Alluvial Aquifer in Northwestern Mississippi by : D. M. Sumner
Download or read book Summary of Results of an Investigation to Define the Geohydrology and Simulate the Effects of Large Ground-water Withdrawals on the Mississippi River Alluvial Aquifer in Northwestern Mississippi written by D. M. Sumner and published by . This book was released on 1984 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Effects of Soil Management Practices on Water Infiltration and Maize Yield to Improve Mississippi River Valley Alluvial Aquifer Sustainability by : Jacob Rix
Download or read book Effects of Soil Management Practices on Water Infiltration and Maize Yield to Improve Mississippi River Valley Alluvial Aquifer Sustainability written by Jacob Rix and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Surface sealing and hardpans in loam soils are problematic in the Mid-South U.S. because of intense tillage. Two experiments quantified the effects of soil management practices on infiltration and maize yield in loam soils. The first study measured the impacts of in-row subsoiling frequency × furrow irrigation frequency. In-row subsoiling significantly improved the infiltration of irrigation but not the infiltration of precipitation. In-row subsoiling with low irrigation frequency is optimal to achieve profitable maize yields while encouraging groundwater conservation. In the second study, six soil management treatments were imposed. For single-ring infiltrometer tests, infiltration rates were different between the two measurement dates but not between measured treatments. In 2022, neutron attenuation data indicated no differences in soil water content between measured treatments. Based on both studies, in-row subsoiling was proven to be an economically viable option in comparison to other Mississippi Delta on-farm conservation practices in the short term.
Book Synopsis Impact of Climate Oscillations/indices on Hydrological Variables in the Mississippi River Valley Alluvial Aquifer by : Meena Raju
Download or read book Impact of Climate Oscillations/indices on Hydrological Variables in the Mississippi River Valley Alluvial Aquifer written by Meena Raju and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Mississippi River Valley Alluvial Aquifer (MRVAA) is one of the most productive agricultural regions in the United States. The main objectives of this research are to identify long term trends and change points in hydrological variables (streamflow and rainfall), to assess the relationship between hydrological variables, and to evaluate the influence of global climate indices on hydrological variables. Non-parametric tests, MMK and Pettitt’s tests were used to analyze trend and change points. PCC and Streamflow elasticity analysis were used to analyze the relationship between streamflow and rainfall and the sensitivity of streamflow to rainfall changes. PCC and MLR analysis were used to evaluate the relationship between climate indices and hydrological variables and the combined effect of climate indices with hydrological variables. The results of the trend analysis indicated spatial variability within the aquifer, increase in streamflow and rainfall in the Northern region of the aquifer, while a decrease was observed in the southern region of the aquifer. Change point analysis of annual maximum, annual mean streamflow and annual precipitation revealed that statistically decreasing shifts occurred in 2001, 1998 and 1995, respectively. Results of PCC analysis indicated that streamflow and rainfall has a strong positive relationship between them with PCC values more than 0.6 in most of the locations within the basin. Results of the streamflow elasticity for the locations ranged from 0.987 to 2.33 for the various locations in the basin. Results of the PCC analysis for monthly maximum and mean streamflow showed significant maximum positive correlation coefficient for Nino 3.4. Monthly maximum rainfall showed a maximum significant positive correlation coefficient for PNA and Nino3.4 and the monthly mean rainfall showed a maximum significant positive correlation coefficient of 0.18 for Nino3.4. Results of the MLR analysis showed a maximum significant positive correlation coefficient of 0.31 for monthly maximum and mean streamflow of 0.21 and 0.23 for monthly maximum and mean rainfall, respectively. Overall, results from this research will help in understanding the impacts of global climate indices on rainfall and subsequently on streamflow discharge, so as to mitigate and manage water resource availability in the MRVAA underlying the LMRB.
Book Synopsis Characterizing Spatial and Temporal Changes and Driving Factors of Groundwater and Surface-water Interactions Within the Mississippi Portion of the Mississippi Alluvial Plain by : Courtney Killian
Download or read book Characterizing Spatial and Temporal Changes and Driving Factors of Groundwater and Surface-water Interactions Within the Mississippi Portion of the Mississippi Alluvial Plain written by Courtney Killian and published by . This book was released on 2018 with total page 89 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Mississippi Alluvial Plain, a robust agricultural region in the South-Central United States, provides commodities across the United States and around the world. Water for irrigation, which is necessary due to irregular rainfall patterns during the growing season, is withdrawn largely from the Mississippi River Valley Alluvial aquifer, one of the most intensely used aquifers in the United States. The groundwater-dependent region has observed recent declines in groundwater and streamflow levels, raising concerns about the availability and use of fresh-water resources. Declining water levels have prompted investigation into the current understanding of groundwater and surface water interaction. Previous research does not adequately quantify the unobservable exchange of water between surface-water bodies and the underlying aquifer. This research was designed to advance the current understanding of the interaction between groundwater and surface water through the quantification of spatial and temporal trends in streamflow and groundwater level changes and the use of high-resolution spatial estimates of streambed hydraulic conductivity. Changes in streamflow and groundwater levels were quantified with the use of hydrograph-separation techniques and trend analyses. High-resolution estimates of streambed hydraulic conductivity were found through the correlation of waterborne continuous resistivity profiling data to hydraulic conductivity and streambed hydraulic conductivity estimates were incorporated into the existing Mississippi Embayment Regional Aquifer Study (MERAS) groundwater-flow model. Site-specific empirical relationships between resistivity and hydraulic conductivity were developed with near-stream borehole geophysical logs to improve model estimates of streambed hydraulic conductivity. Results of the quantification of changes in streamflow and groundwater levels suggested agricultural groundwater withdrawals for irrigation to be the primary source of groundwater-level declines. Results from the incorporation of high-resolution estimates of streambed hydraulic conductivity showed that the existing groundwater-flow model is sensitive to changes in streambed hydraulic conductivity, which may impact model accuracy. The incorporation of streambed hydraulic conductivity estimates derived from site-specific empirical relationships impacted MERAS model water-budget estimates. Information gained from this research will be used to improve the existing groundwater-flow model, which acts as a decision-support tool for water-resource managers at state and local levels to make informed water-use decisions for the conservation of fresh-water resources for sustainable agricultural irrigation practices.
Book Synopsis Changes in the Volume of Water in the Mississippi River Alluvial Aquifer in the Delta, Northwestern Mississippi, 1980-94 by : J. Kerry Arthur
Download or read book Changes in the Volume of Water in the Mississippi River Alluvial Aquifer in the Delta, Northwestern Mississippi, 1980-94 written by J. Kerry Arthur and published by . This book was released on 1995 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Characterizing Spatial and Temporal Changes and Driving Factors of Groundwater and Surface-water Interactions Within the Mississippi Portion of the Mississippi Alluvial Plain by :
Download or read book Characterizing Spatial and Temporal Changes and Driving Factors of Groundwater and Surface-water Interactions Within the Mississippi Portion of the Mississippi Alluvial Plain written by and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Mississippi Alluvial Plain, a robust agricultural region in the South-Central United States, provides commodities across the United States and around the world. Water for irrigation, which is necessary due to irregular rainfall patterns during the growing season, is withdrawn largely from the Mississippi River Valley Alluvial aquifer, one of the most intensely used aquifers in the United States. The groundwater-dependent region has observed recent declines in groundwater and streamflow levels, raising concerns about the availability and use of fresh-water resources. Declining water levels have prompted investigation into the current understanding of groundwater and surface-water interaction. Previous research does not adequately quantify the unobservable exchange of water between surface-water bodies and the underlying aquifer. This research was designed to advance the current understanding of the interaction between groundwater and surface water through the quantification of spatial and temporal trends in streamflow and groundwater level changes and the use of high-resolution spatial estimates of streambed hydraulic conductivity. Changes in streamflow and groundwater levels were quantified with the use of hydrograph-separation techniques and trend analyses. High-resolution estimates of streambed hydraulic conductivity were found through the correlation of waterborne continuous resistivity profiling data to hydraulic conductivity and streambed hydraulic conductivity estimates were incorporated into the existing Mississippi Embayment Regional Aquifer Study (MERAS) groundwater-flow model. Site-specific empirical relationships between resistivity and hydraulic conductivity were developed with near-stream borehole geophysical logs to improve model estimates of streambed hydraulic conductivity. Results of the quantification of changes in streamflow and groundwater levels suggested agricultural groundwater withdrawals for irrigation to be the primary source of grou
Book Synopsis A GIS Approach to Modeling Groundwater Levels in the Mississippi River Valley Alluvial Aquifer by : Josef Orion Lilly
Download or read book A GIS Approach to Modeling Groundwater Levels in the Mississippi River Valley Alluvial Aquifer written by Josef Orion Lilly and published by . This book was released on 2016 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Climate Change Effects on Groundwater Resources by : Holger Treidel
Download or read book Climate Change Effects on Groundwater Resources written by Holger Treidel and published by CRC Press. This book was released on 2011-12-02 with total page 422 pages. Available in PDF, EPUB and Kindle. Book excerpt: Climate change is expected to modify the hydrological cycle and affect freshwater resources. Groundwater is a critical source of fresh drinking water for almost half of the world’s population and it also supplies irrigated agriculture. Groundwater is also important in sustaining streams, lakes, wetlands, and associated ecosystems. But despite this, knowledge about the impact of climate change on groundwater quantity and quality is limited. Direct impacts of climate change on natural processes (groundwater recharge, discharge, storage, saltwater intrusion, biogeochemical reactions, chemical fate and transport) may be exacerbated by human activities (indirect impacts). Increased groundwater abstraction, for example, may be needed in areas with unsustainable or contaminated surface water resources caused by droughts and floods. Climate change effects on groundwater resources are, therefore, closely linked to other global change drivers, including population growth, urbanization and land-use change, coupled with other socio-economic and political trends. Groundwater response to global changes is a complex function that depends on climate change and variability, topography, aquifer characteristics, vegetation dynamics, and human activities. This volume contains case studies from diverse aquifer systems, scientific methods, and climatic settings that have been conducted globally under the framework of the UNESCO-IHP project Groundwater Resources Assessment under the Pressures of Humanity and Climate Change (GRAPHIC). This book presents a current and global synthesis of scientific findings and policy recommendations for scientists, water managers and policy makers towards adaptive management of groundwater sustainability under future climate change and variability.
Book Synopsis Streamflow depletion by wells by : Paul M. Barlow
Download or read book Streamflow depletion by wells written by Paul M. Barlow and published by . This book was released on 2012 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Groundwater Modeling for Mississippi River Alluvial Aquifer of Northeastern Louisiana by : Ramazan Karakullukcu
Download or read book Groundwater Modeling for Mississippi River Alluvial Aquifer of Northeastern Louisiana written by Ramazan Karakullukcu and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Climate Change and Groundwater: Planning and Adaptations for a Changing and Uncertain Future by : Robert Maliva
Download or read book Climate Change and Groundwater: Planning and Adaptations for a Changing and Uncertain Future written by Robert Maliva and published by Springer Nature. This book was released on 2021-01-26 with total page 357 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book attempts to bridge the gap between the climate change research and decision-making communities by exploring the impacts of climate change on groundwater from a more applied perspective. Global climate change will impact groundwater demands, quality, and available supplies, and rising sea level may cause water tables to rise, inundating low-lying coastal areas. Groundwater will increasingly be needed to perform a stabilization role in mitigating fluctuations in the supply of surface waters, serving as a buffer against droughts. Climate change has become a frequent subject in the mass media, and the academic literature on the subject is now enormous. An impediment to climate change adaptation with respect to water is a poor link between the climate change research community and the actual decision-makers responsible for water supply planning. Key issues explored are methods for evaluating potential impacts on climate change on local groundwater systems, the adaptation of decision-making process, and how climate change adaptation can be mainstreamed into the water supply planning.
Book Synopsis Selected Water Resources Abstracts by :
Download or read book Selected Water Resources Abstracts written by and published by . This book was released on 1991-04 with total page 1200 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Hydrologic Models and Analysis of Water Availability in Cuyama Valley, California by :
Download or read book Hydrologic Models and Analysis of Water Availability in Cuyama Valley, California written by and published by . This book was released on 2014 with total page 166 pages. Available in PDF, EPUB and Kindle. Book excerpt: Changes in population, agricultural development practices (including shifts to more water-intensive crops), and climate variability are placing increasingly larger demands on available water resources, particularly groundwater, in the Cuyama Valley, one of the most productive agricultural regions in Santa Barbara County. The goal of this study was to produce a model capable of being accurate at scales relevant to water management decisions that could be considered in the evaluation of the sustainable water supply. The Cuyama Valley Hydrologic Model (CUVHM) was designed to simulate the most important natural and human components of the hydrologic system, including components dependent on variations in climate, thereby providing a reliable assessment of groundwater conditions and processes that can inform water users and help to improve planning for future conditions. Model development included a revision of the conceptual model of the flow system, construction of a precipitation-runoff model using the Basin Characterization Model (BCM), and construction of an integrated hydrologic flow model with MODFLOW-One-Water Hydrologic Flow Model (MF-OWHM). The hydrologic models were calibrated to historical conditions of water and land use and, then, used to assess the use and movement of water throughout the Valley. These tools provide a means to understand the evolution of water use in the Valley, its availability, and the limits of sustainability. The conceptual model identified inflows and outflows that include the movement and use of water in both natural and anthropogenic systems. The groundwater flow system is characterized by a layered geologic sedimentary sequence that--in combination with the effects of groundwater pumping, natural recharge, and the application of irrigation water at the land surface--displays vertical hydraulic-head gradients. Overall, most of the agricultural demand for water in the Cuyama Valley in the initial part of the growing season is supplied by groundwater, which is augmented by precipitation during wet winter and spring seasons. In addition, the amount of groundwater used for irrigation varies from year to year in response to climate variation and can increase dramatically in dry years. Model simulation results, however, also indicated that irrigation may have been less efficient during wet years. Agricultural pumpage is a major component to simulated outflow that is often poorly recorded. Therefore, an integrated, coupled farm-process model is used to estimate historical pumpage for water-balance subregions that evolved with the development of groundwater in the Valley from 1949 through 2010. The integrated hydrologic model includes these water-balance subregions and delineates natural, municipal, and agricultural land use; streamflow networks; and groundwater flow systems. The redefinition of the geohydrologic framework (including the internal architecture of the sedimentary units) and incorporation of these units into the simulation of the regional groundwater flow system indicated that faults have compartmentalized the alluvial deposits into subregions, which have responded differently to regional groundwater flow, locations of recharge, and the effects of development. The Cuyama Valley comprises nine subregions grouped into three regional zones, the Main, Ventucopa Uplands, and Sierra Madre Foothills, which are fault bounded, represent different proportions of the three alluvial aquifers, and have different water quality. The CUVHM uses MF-OWHM to simulate and assess the use and movement of water, including the evolution of land use and related water-balance regions. The model is capable of being accurate at annual to interannual time frames and at subregional to valley-wide spatial scales, which allows for analysis of the groundwater hydrologic budget for the water years 1950-2010, as well as potential assessment of the sustainable use of groundwater. Simulated changes in storage over time showed that significant withdrawals from storage generally occurred not only during drought years (1976-77 and 1988-92) but also during the early stages of industrial agriculture, which was initially dominated by alfalfa production. Since the 1990s, agriculture has shifted to more water-intensive crops. Measured and simulated groundwater levels indicated substantial declines in selected subregions, mining of groundwater that is thousands to tens of thousands of years old, increased groundwater storage depletion, and land subsidence. Most of the recharge occurs in the upland regions of Ventucopa and Sierra Madre Foothills, and the largest fractions of pumpage and storage depletion occur in the Main subregion. The long-term imbalance between inflows and outflows resulted in simulated overdraft (groundwater withdrawals in excess of natural recharge) of the groundwater basin over the 61-year period of 1949-2010. Changes in storage varied considerably from year to year, depending on land use, pumpage, and climate conditions. Climatically driven factors can greatly affect inflows, outflows, and water use by more than a factor of two between wet and dry years. Although precipitation during inter-decadal wet years previously replenished the basin, the water use and storage depletion have lessened the effects of these major recharge events. Simulated and measured water-level altitudes indicated the presence of large areas where depressed water levels have resulted in large desaturated zones in the younger and Older Alluvium layers in the Main-zone subregions. The results of modeled projection of the base-case scenario 61 years into the future indicated that current supply-and-demand are unsustainable and will result in additional groundwater-level declines and related storage depletion and land subsidence. The reduced-supply and reduced-demand projections reduced groundwater storage depletion but may not allow for sustainable agriculture under current demands, agricultural practices, and land use.
