Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons™

Open Access. Powered by Scholars. Published by Universities.®

Groundwater

Discipline
Institution
Publication Year
Publication
Publication Type
File Type

Articles 361 - 390 of 979

Full-Text Articles in Physical Sciences and Mathematics

An Inter-Watershed Comparison Study Of Bedrock Controls On Shallow Subsurface Flow And Streamflow Response, Robert Livesay Jan 2018

An Inter-Watershed Comparison Study Of Bedrock Controls On Shallow Subsurface Flow And Streamflow Response, Robert Livesay

Graduate Student Theses, Dissertations, & Professional Papers

Bedrock controls on watershed response have been actively studied in recent years, however, most conclusions are based on surface water analysis leaving unresolved questions about the nature of bedrock flow paths and ultimately their control on watershed response. In this study, we investigated bedrock controls on watershed response by simultaneously monitoring the hydrology of two adjacent watersheds underlain by dissimilar geologic formations (monzonite vs. meta-sandstone) and by characterizing subsurface conditions through bedrock drilling and fracture mapping. We hypothesized, when soils saturate, the underlying bedrock geology may influence the partitioning of shallow subsurface flow (SSF) between soil and bedrock flow paths, …

Go to article

Using Multiple Environmental Tracers To Investigate The Relative Role Of Soil And Deep Groundwater In Stream Water Generation For A Snow-Dominated Headwater Catchment, Isabellah V. Von Trapp Jan 2018

Using Multiple Environmental Tracers To Investigate The Relative Role Of Soil And Deep Groundwater In Stream Water Generation For A Snow-Dominated Headwater Catchment, Isabellah V. Von Trapp

Graduate Student Theses, Dissertations, & Professional Papers

In this study, seasonal fluctuation of environmental tracers in stream flow, soil water, and deep bedrock groundwater were used to constrain the role of deep bedrock groundwater in streamflow generation for a mountainous headwater catchment. Synoptic measurements of stream discharge, 222Rn, specific conductivity and major ion concentrations were measured throughout the water year over a 5 km reach of Cap Wallace Creek in the Lubrecht Experimental Forest, Montana, U.S.A. with the intention of understanding groundwater – surface water interactions across spatial and temporal scales. Stage measurements were continually recorded at seven stilling well locations along the reach. Discharge measurements …

Go to article

Estimating Groundwater Inflow And Age Characteristics In An Alluvial Aquifer Along The Little Wind River, Wyoming, Derek Goble Jan 2018

Estimating Groundwater Inflow And Age Characteristics In An Alluvial Aquifer Along The Little Wind River, Wyoming, Derek Goble

Graduate Student Theses, Dissertations, & Professional Papers

We synoptically sampled a 2 km gaining reach of the Little Wind River in central Wyoming for 222Rn, CFCs and SF6 to determine the distributed volumes and locations of discharge and estimate alluvial groundwater age characteristics. 222Rn was sampled in the stream, shallow in-stream piezometers and nearby alluvial groundwater wells to determine the volume and spatial distribution of groundwater discharge to the river. Age tracers, CFC and SF6, sampled in the stream, shallow in-stream piezometers and in alluvial groundwater wells were then used to determine whether in-stream samples are capable of constraining the residence time distribution …

Go to article

An Lntegrated Approach (Remote Sensing, Hydrogeology, Geotechnical, And Geoinformatics) To Assess And Monitor Fossil Aquifers And Associated Land Deformation Over The Arabian Peninsula, Abdullah Ghurmullah Saeed Othman Dec 2017

An Lntegrated Approach (Remote Sensing, Hydrogeology, Geotechnical, And Geoinformatics) To Assess And Monitor Fossil Aquifers And Associated Land Deformation Over The Arabian Peninsula, Abdullah Ghurmullah Saeed Othman

Dissertations

Deformational features such as subsidence, sinkholes, fissures, settling and cracks in buildings and structures, and earthquakes are being reported from many of the world’s arid lands, in areas where fossil aquifers are being excessively exploited. Using the Lower Mega Aquifer System (LMAS) in Arabia as a test site, I applied an integrated approach (remote sensing, geodesy, GIS, geology, hydrogeology, and geotechnical) to identify nature, intensity, spatial distribution, and factors controlling the observed deformation in the central (Al-Qassim and Ha'il regions; area: 16×10⁴ km²) and the northern (Wadi As-Sirhan Basin; area: ~10.9×10⁴ km²) Arabia. A four -fold approach was adopted to …

Go to article

Ncer Assistance Agreement Annual Progress Report For Grant #83582401 - Assessment Of Stormwater Harvesting Via Manage Aquifer Recharge (Mar) To Develop New Water Supplies In The Arid West: The Salt Lake Valley Example, Ryan Dupont, Joan E. Mclean, Richard C. Peralta, Sarah E. Null, Douglas B. Jackson-Smith Nov 2017

Ncer Assistance Agreement Annual Progress Report For Grant #83582401 - Assessment Of Stormwater Harvesting Via Manage Aquifer Recharge (Mar) To Develop New Water Supplies In The Arid West: The Salt Lake Valley Example, Ryan Dupont, Joan E. Mclean, Richard C. Peralta, Sarah E. Null, Douglas B. Jackson-Smith

Civil and Environmental Engineering Faculty Publications

The aims of the original proposed project remain the same, that is, to test the hypothesis that Managed Aquifer Recharge (MAR) for stormwater harvesting is a technically feasible, socially and environmentally acceptable, economically viable, and legally feasible option for developing new water supplies for arid Western urban ecosystems experiencing increasing population, and climate change pressures on existing water resources. The project is being carried out via three distinct but integrated components that include: 1) Monitoring of existing distributed MAR harvesting schemes involving a growing number of demonstration Green Infrastructure (GI) test sites; 2) Integrated stormwater/vadose zone/groundwater/ ecosystem services modeling; and …

Go to article

Econometric Estimation Of Groundwater Depth Change For The High Plains Aquifer, Jonathan R. Sims Nov 2017

Econometric Estimation Of Groundwater Depth Change For The High Plains Aquifer, Jonathan R. Sims

Department of Agricultural Economics: Dissertations, Theses, and Student Research

This article presents a new method for estimating changes in depth to groundwater at a yearly, county level and incorporates these estimates as the dependent variable of econometric models for the High Plains aquifer. The High Plains (Ogallala) aquifer underlies eight states in the central United States and is the primary source of irrigation water for this large food producing region. The stock of groundwater is a finite, non-renewable resource with minimal recharge in most areas. Many fields of study, including hydrology and agricultural economics, are interested in depth to groundwater changes because they serve as a proxy for estimating …

Go to article

Groundwater And Subsurface Water In A Landscape With Shallow Bedrock: Implications For Agricultural Nutrient Export, Laura Kelley, Hunter R. Evans, Reid E. Buskirk, Jonathan M. Malzone, Walter S. Borowski Nov 2017

Groundwater And Subsurface Water In A Landscape With Shallow Bedrock: Implications For Agricultural Nutrient Export, Laura Kelley, Hunter R. Evans, Reid E. Buskirk, Jonathan M. Malzone, Walter S. Borowski

EKU Faculty and Staff Scholarship

Controls on nutrient export from agricultural landscapes include regional hydrological and geological conditions. In many central Kentucky basins shallow fractured bedrock produces focused groundwater discharge and flashy runoff events. Eastern Kentucky University’s Meadowbrook Farm is currently experimenting with nutrient sequestration techniques; however the effectiveness of these techniques given the local hydrogeology needs to be quantified. Our objective was to determine the potential pathways for nutrient export by mapping key hydrologic features and using a watershed approach. The key features mapped were springs, tile drains, runoff channels, land use and the underlying geology. We chose a 0.46 km2 watershed to …

Go to article

2017, October - Recommendations To Address The Expansion Of Seawater Intrusion In The Salinas Valley Groundwater Basin Oct 2017

2017, October - Recommendations To Address The Expansion Of Seawater Intrusion In The Salinas Valley Groundwater Basin

Monterey County Water Resources Agency Engineering Reports

This report provides a discussion of the current knowledge and related background information surrounding seawater intrusion pathways and potential impacts thereof on the Salinas Valley Groundwater Basin. The report also serves as a body of evidence to catalogue the findings used to support the six recommendations presented. Each recommendation can be implemented on its own or in concert with the others, and the relative importance of each is discussed individually in this report. However, the recommendations are conceptualized as a comprehensive solution that, along with continued operation of projects that have been constructed for the same purpose, have the strongest …

Go to article

Diurnal And Seasonal Variation In Groundwater Nitrate -N Concentration In A Saturated Buffer Zone, Joseph Miller Oct 2017

Diurnal And Seasonal Variation In Groundwater Nitrate -N Concentration In A Saturated Buffer Zone, Joseph Miller

Theses and Dissertations

Surface water pollution by nitrate (NO3-) is identified as a critical problem in agricultural land-use areas. Excess NO3- loading causes eutrophication and hypoxia in near-shore marine waters such as the Gulf of Mexico. Diversion of agricultural runoff into saturated buffer zones reduces NO3- loading. Although the mechanisms responsible for NO3- reduction in saturated buffer zones are well characterized, little is known about how NO3- concentrations vary temporally and what factors control those changes. The objective of this study is to understand NO3- concentration and environmental factor variability in a saturated buffer zone on a diurnal scale within and among the …

Go to article

2017, October - Recommendations To Address The Expansion Of Seawater Intrusion In The Salinas Valley Groundwater Basin Sep 2017

2017, October - Recommendations To Address The Expansion Of Seawater Intrusion In The Salinas Valley Groundwater Basin

Monterey County Water Resources Agency Water Reports

This report provides a discussion of the current knowledge and related background information surrounding seawater intrusion pathways and potential impacts thereof on the Salinas Valley Groundwater Basin. The report also serves as a body of evidence to catalogue the findings used to support the six recommendations presented. Each recommendation can be implemented on its own or in concert with the others, and the relative importance of each is discussed individually in this report. However, the recommendations are conceptualized as a comprehensive solution that, along with continued operation of projects that have been constructed for the same purpose, have the strongest …

Go to article

Vulnerability Assessment Of Groundwater To No3 Contamination Using Gis, Drastic Model And Geostatistical Analysis, Adela Beauty Adu Agyemang Aug 2017

Vulnerability Assessment Of Groundwater To No3 Contamination Using Gis, Drastic Model And Geostatistical Analysis, Adela Beauty Adu Agyemang

Electronic Theses and Dissertations

The study employed Geographical Information System (GIS) technology to investigate the vulnerability of groundwater to NO3 content in Buncombe County, North Carolina in two different approaches. In the first study, the spatial distribution of NO3 contamination was analyzed in a GIS environment using Kriging Interpolation. Cokriging interpolation was used to establish how NO3 relates to land cover types and depth to water table of wells in the county. The second study used DRASTIC model to assess the vulnerability of groundwater in Buncombe County to NO3 contamination. To get an accurate vulnerability index, the DRASTIC parameters were …

Go to article

Groundwater Flow Tracing In Carter Saltpeter Cave And Toll Branch, Carter County, Tn, Aaron G. Doyka Aug 2017

Groundwater Flow Tracing In Carter Saltpeter Cave And Toll Branch, Carter County, Tn, Aaron G. Doyka

Electronic Theses and Dissertations

Groundwater tracing studies have shown a well-developed conduit system in the karst aquifer beneath the Buffalo Creek Watershed of Carter County, TN. Groundwater can quickly travel beneath topographic divides, transporting contaminants. Using GIS and field reconnaissance, two sites were selected for a two phase dye trace study. In May-June 2016 groundwater resurgences were located using activated carbon samplers, and in October-December 2016 flow velocities were measured using ISCO automatic water samplers. In study 1, a stream sinking in the back of Carter Saltpeter Cave was traced to its resurgence at Cave Springs Cave. In study 2, the dye mass centroid …

Go to article

2015 – Project Justification – Addressing An Urgent Water Supply Need For A Disadvantaged Community In The Greater Monterey County Irwm Region Jul 2017

2015 – Project Justification – Addressing An Urgent Water Supply Need For A Disadvantaged Community In The Greater Monterey County Irwm Region

Miscellaneous Monterey and San Luis Obispo County Documents and Reports

One hundred percent of Castroville’s water supply comes from the 400-foot aquifer of the Pressure sub-basin of the Salinas Valley Groundwater Basin. Groundwater levels in the aquifer dropped more than 100 feet below the seal level as of July 2015 at static conditions. Water levels dropped to more than 190 feet below the mean sea level during operation of the water well. The dramatic drop combined with the close proximity of the Pacific Ocean (less than 4 miles) and to existing seawater intrusion (less than ¼ mile) raised significant alarm that the existing water supply system to Castroville was imminently …

Go to article

2015, November - Salinas River Salt Modeling Report , Tetra Tech For California Central Coast Regional Water Quality Control Board And Us Environmental Protection Agency, Region Ix Jul 2017

2015, November - Salinas River Salt Modeling Report , Tetra Tech For California Central Coast Regional Water Quality Control Board And Us Environmental Protection Agency, Region Ix

State and Federal Documents Relating to Monterey and San Luis Obispo Counties

Report prepared by Tetra Tech on behalf of California Central Coast Regional Water Quality Control Board and US Environmental Protection Agency, Region IX with a view of development of salt-related TMDLs and a salt and nutrient management plan for the Salinas Valley aquifers. The report provides data analysis and a literature review, development of a water and salt mass balance tool, and salt sources assessment. Recommendations regarding improved representation of cropland locations, rotations, and irrigation practices are provided.

Go to article

1999 - Salinas River Watershed Management Action Plan, Central Coast Regional Water Quality Control Board Jul 2017

1999 - Salinas River Watershed Management Action Plan, Central Coast Regional Water Quality Control Board

Miscellaneous Monterey and San Luis Obispo County Documents and Reports

To more effectively protect and improve water resources, the Action Plan attempts to develop local solutions to local problems. Many significant identified water quality impacts in the Salinas River Watershed, such as erosion and sedimentation, nitrates in the groundwater and surface water, and older, discontinued pesticides in sediments and animal tissues, are primarily associated with nonpoint pollution sources. Also, widespread groundwater pumping contributes significantly to seawater intrusion into the coastal aquifers. The Action Plan approach includes: 1. devoting additional Regional Board resources to watershed activities, 2. increasing the Regional Board presence by developing partnerships with landowners, local governments, resource agencies …

Go to article

1999 - Water Resources And Land Use Change In Salinas Valley, Watershed Institute Report No. Wi-1999-01 Jul 2017

1999 - Water Resources And Land Use Change In Salinas Valley, Watershed Institute Report No. Wi-1999-01

Miscellaneous Monterey and San Luis Obispo County Documents and Reports

The 1999 report prepared by Fred Watson, Lars Pierce, Mel Mulitsch, Wendi Newman, Adrian Rocha, Mark Fain and Jodiah Nelson of the Watershed Institute, describes the progress made toward the use of computer modeling to provide both understanding and predictive capability. The Salinas River watershed of over 11,000 square kilometers supports large areas of intensive agriculture production, including large areas of intensive crop production, and extensive cattle ranches supporting annual grasslands. Mainly a dry climate with limited surface water resources, the valley has a finite groundwater system. Agriculture accounts for 93.5% of the groundwater extractions that exceed recharge by 40,000-50,000 …

Go to article

2015, Aug. 20 - Groundwater Recharge On East Side Soils Of The Salinas Valley Jul 2017

2015, Aug. 20 - Groundwater Recharge On East Side Soils Of The Salinas Valley

Miscellaneous Monterey and San Luis Obispo County Documents and Reports

Discussion of the historically low groundwater levels in the Salinas Valley, noting that the shallower wells have become unreliable. As the groundwater levels drop below sea level, the seawater intrusion in the coastal aquifers will worsen. Because of the fast-declining groundwater levels on the east side of the Salinas Valley, the potential for seawater moving inland increases. Enhancing recharge in these areas would be beneficial in reducing seawater intrusion while lowering flood risk and erosion damage. The article reviews potential strategies to increase infiltration of rainwater during winter storms thereby recharging the underlying aquifer.

Go to article

Tracking Potential Leakage Of Tailings-Lake Water Into Background Groundwater In Butte, Montana, Using Geochemical And Stable Isotope Tracers, Matthew Berzel Jul 2017

Tracking Potential Leakage Of Tailings-Lake Water Into Background Groundwater In Butte, Montana, Using Geochemical And Stable Isotope Tracers, Matthew Berzel

Graduate Theses & Non-Theses

This study was conducted to identify environmental tracers using water chemistry and stable isotopes in the Moulton Road area adjacent to the Yankee Doodle tailings impoundment north of Butte, Montana. The water level of the tailings lake is being raised as tailings slurry is pumped up to the impoundment, and numerous residential wells are located in close proximity. Although it has an alkaline pH (> 9), the water in the tailings lake is much higher in some chemical constituents than the wells and some of these constituents could be used as tracers to determine if lake water is migrating out …

Go to article

2013-2014, August - Integrated Regional Water Management Plan For The Greater Monterey County Region Jun 2017

2013-2014, August - Integrated Regional Water Management Plan For The Greater Monterey County Region

Miscellaneous Monterey and San Luis Obispo County Documents and Reports

An Integrated Regional Water Management Plan (IRWM Plan) developed by 18 member entities that include government agencies, nonprofit organizations, educational organizations, water service districts, private water companies, and organizations representing agricultural, environmental, and community interests. The IRWM Plan is an expansion and modification of a previous plan – the May 2006 Salinas Valley Integrated Regional Water Management Functionally Equivalent Plan developed by Monterey County Water Resources Agency. While the traditional approach to water resource management has typically involved separate and distinct agencies managing different aspects of the water system, i.e., water supply, water quality, flood management, and natural resources, integrated …

Go to article

Evaluation Of A Filtration Sorbent For Remediation Of Arsenic In Groundwater, Clement Do Jun 2017

Evaluation Of A Filtration Sorbent For Remediation Of Arsenic In Groundwater, Clement Do

Electronic Theses, Projects, and Dissertations

A commercially available product, PURA PhosLock, was identified and evaluated for use as a sorbent to remove dissolved arsenic (As) from drinking water. Although marketed as a product to remove phosphate in aquaria, it is composed of iron oxide hydroxide (i.e., FeO(OH)), which is also known to adsorb dissolved As species from water. Arsenic was measured using standard methods and Graphite Furnace Atomic Absorption Spectroscopy. A first rough filtration test was performed to see if the PhosLock adsorbed As well. About 50 g of PhosLock was used to filter 10 L of tap water containing 100 ppb As. No detectable …

Go to article

Groundwater Vulnerability Assessment For Nitrate Pollution In The Salinas Valley Using A Modified Drastic Model, Bernadette Boyle May 2017

Groundwater Vulnerability Assessment For Nitrate Pollution In The Salinas Valley Using A Modified Drastic Model, Bernadette Boyle

Master's Projects and Capstones

Groundwater is an integral piece of California’s groundwater resources. One of the most common contaminants present in groundwater is nitrate. Nitrate contamination is often a result of agricultural land use activities on the ground surface. The study area for this analysis is the Salinas Valley Groundwater Basin, an agriculturally dominated basin in coastal California. The Salinas Valley Basin is both one of the most agriculturally productive areas of the state, as well as one of the most nitrate-contaminated basins in the state. The purpose of this research was to develop a groundwater vulnerability map for nitrate pollution in the Salinas …

Go to article

A Global Synthesis Of Managing Groundwater Dependent Ecosystems Under Sustainable Groundwater Policy, Melissa M. Rohde, Raymond H. Froend, Jeanette Howard May 2017

A Global Synthesis Of Managing Groundwater Dependent Ecosystems Under Sustainable Groundwater Policy, Melissa M. Rohde, Raymond H. Froend, Jeanette Howard

Research outputs 2014 to 2021

Groundwater is a vital water supply worldwide for people and nature. However, species and ecosystems that depend on groundwater for some or all of their water needs, known as groundwater dependent ecosystems (GDEs), are increasingly becoming threatened worldwide due to growing human water demands. Over the past two decades, the protection and management of GDEs have been incorporated into several water management policy initiatives worldwide including jurisdictions within Australia, the European Union, South Africa, and the United States. Among these, Australia has implemented the most comprehensive framework to manage and protect GDEs through its water policy initiatives. Using a science-based …

Go to article

Characterizing Subsurface Void Spaces And Water Distribution And Flow Patterns In Cave Hill Karst Using Resistivity, Jacob A. Gochenour May 2017

Characterizing Subsurface Void Spaces And Water Distribution And Flow Patterns In Cave Hill Karst Using Resistivity, Jacob A. Gochenour

Senior Honors Projects, 2010-2019

Describing the distribution of groundwater is essential in understanding the evolution of geomorphologic features in karst topography. Electrical resistivity allows us to find a model of subsurface distribution of resistivity that enables the visual recognition of groundwater and void spaces. The purpose of this research is to implement electrical resistivity to describe the spatial relationship of groundwater and karstic features at Grand Caverns National Natural Landmark, Grottoes, Virginia. Two locations of interest, a karstic swale and sinkhole area, were identified for the deployment of electrical resistivity. Both, dipole-dipole and Schlumberger arrays were collected for each deployment. A total of ten …

Go to article

The Groundwater Atlas Of Richardson County, Nebraska, Dana P. Divine, Leslie M. Howard May 2017

The Groundwater Atlas Of Richardson County, Nebraska, Dana P. Divine, Leslie M. Howard

Conservation and Survey Division: Faculty and Staff Publications

The purpose of this groundwater atlas is to synthesize a wealth of hydrogeologic data for Richardson County that has not been published in readily accessible formats previously. Many of the maps presented herein are based on data from registered well logs and test hole logs that are publicly available on-line, which become more valuable when compiled, analyzed, and discussed as a whole. The focus of the maps presented in this report is the accessibility of groundwater for pumping.

Go to article

An Analysis Of The Relationship Between Snowpack And Groundwater Across Utah Watersheds., Samuel Wright May 2017

An Analysis Of The Relationship Between Snowpack And Groundwater Across Utah Watersheds., Samuel Wright

Electronic Theses and Dissertations

This thesis examined what type of relationship existed between snow water equivalence (SWE) volume and groundwater elevation within six sub-watersheds in Utah. Data was gathered on SWE from seventeen SNOTEL sites and groundwater elevation data was gathered from six continuously monitored groundwater wells. This data was gathered for January through May for 2011, 2013, and 2014 in order to represent the water conditions that were above average, below average, and average respectively. Using MLR formulas the total SWE for each sub-watershed was determined for each year/month. Afterwards a correlation analysis was performed to determine if any association existed between SWE …

Go to article

Groundwater And Tidal Controls On Wetland Hydrology, Julie J. Metz Wetland Mitigation Bank, Woodbridge, Virginia, Benjamin Stuart Hiza Apr 2017

Groundwater And Tidal Controls On Wetland Hydrology, Julie J. Metz Wetland Mitigation Bank, Woodbridge, Virginia, Benjamin Stuart Hiza

OES Theses and Dissertations

Julie J. Metz Wetlands Mitigation Bank, a 92-hectare freshwater wetland located in Woodbridge, Virginia, borders the tidally-influenced Neabsco Creek. Seven pods separated by earthen berms were built by Wetland Studies and Solutions Inc. (WSSI) in 1995 and 1997 by removing the toe of small sandy alluvial fans and covering the underlying coarse gravel bed with a low permeability cap. The basal Quaternary gravels were deposited in a creek valley incised into a thick sand-and-clay Cretaceous delta. The alluvial-fan apron developed at the base of steep slopes along the sides of the valley. Pressure transducer data from five monitoring wells along …

Go to article

Modeling The Movement Of Septic Water Chloride Through A Soil Profile, Shawkat Kochary, Tom Byl, Bahzad Noori Mar 2017

Modeling The Movement Of Septic Water Chloride Through A Soil Profile, Shawkat Kochary, Tom Byl, Bahzad Noori

Civil and Architectural Engineering Faculty Research

The purpose of this study was to investigate the movement of chloride through a vadose zone located under failed and non-regulated septic tanks of Duhok city, Kurdistan of Iraq, potentially contaminating its groundwater. A physical vadose model (PVM) of a vertical flow direction was built in the laboratory to represent the city soil profile. The size of the PVM was 210 × 122 × 9.7 cm (height, width, and depth). Preliminary soil tests were conducted to better represent the lithology of study area. The PVM was then packed with regional silt clay soil, after modifying its texture, using an innovative …

Go to article

Using Remote Sensing To Evaluate Wetland Recovery In The Northern Tampa Bay Area Following Reduction In Groundwater Withdrawals, Amor Elder Mar 2017

Using Remote Sensing To Evaluate Wetland Recovery In The Northern Tampa Bay Area Following Reduction In Groundwater Withdrawals, Amor Elder

USF Tampa Graduate Theses and Dissertations

In the past, the Northern Tampa Bay Area (NTBA) wetlands saw severe declines in hydrologic conditions due to excessive groundwater withdrawal rates. Eventually these rates were reduced to allow the wetlands to recover. To monitor this recovery, the Southwest Florida Water Management district (SWFWMD) set up a fieldwork based scoring methodology, called the Wetlands Assessment Procedure (WAP). WAP has been used in many studies of the area since groundwater withdrawal reductions; with many of those studies finding the recovery to be mixed at best. However, these studies were very limited in the number of wetlands they could assess due to …

Go to article

Estimating The Permanent Loss Of Groundwater Storage In The Southern San Joaquin Valley, California, Ryan G. Smith, Rosemary Knight, J. Chen, J. A. Reeves, H. A. Zebker, T. Farr, Z. Liu Mar 2017

Estimating The Permanent Loss Of Groundwater Storage In The Southern San Joaquin Valley, California, Ryan G. Smith, Rosemary Knight, J. Chen, J. A. Reeves, H. A. Zebker, T. Farr, Z. Liu

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

In the San Joaquin Valley, California, recent droughts starting in 2007 have increased the pumping of groundwater, leading to widespread subsidence. In the southern portion of the San Joaquin Valley, vertical subsidence as high as 85 cm has been observed between June 2007 and December 2010 using Interferometric Synthetic Aperture Radar (InSAR). This study seeks to map regions where inelastic (not recoverable) deformation occurred during the study period, resulting in permanent compaction and loss of groundwater storage. We estimated the amount of permanent compaction by incorporating multiple data sets: the total deformation derived from InSAR, estimated skeletal-specific storage and hydraulic …

Go to article

A Self-Calibrating Runoff And Streamflow Remote Sensing Model For Ungauged Basins Using Open-Access Earth Observation Data, A Poortinga, W Bastiaanssen, G Simons, David Saah, G Senay, M Fenn, B Bean, J Kadyszewski Jan 2017

A Self-Calibrating Runoff And Streamflow Remote Sensing Model For Ungauged Basins Using Open-Access Earth Observation Data, A Poortinga, W Bastiaanssen, G Simons, David Saah, G Senay, M Fenn, B Bean, J Kadyszewski

Environmental Science

Due to increasing pressures on water resources, there is a need to monitor regional water resource availability in a spatially and temporally explicit manner. However, for many parts of the world, there is insufficient data to quantify stream flow or ground water infiltration rates. We present the results of a pixel-based water balance formulation to partition rainfall into evapotranspiration, surface water runoff and potential ground water infiltration. The method leverages remote sensing derived estimates of precipitation, evapotranspiration, soil moisture, Leaf Area Index, and a single F coefficient to distinguish between runoff and storage changes. The study produced significant correlations between …

Go to article

First Prev Next Last