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This report gives an overview of U.S. Geological Survey, Illinois District, Water Resources Division activities related to the water resources of the State of Illinois. The report includes sections describing District organization, programs, water conditions, data collection activities, and project summaries. Also included is a complete listing of District and Illinois-related USGS publications.
This report gives an overview of U.S. Geological Survey, Illinois District, Water Resources Division activities related to the water resources of the State of Illinois. The report includes sections describing District organization, programs, water conditions, data collection activities, and project summaries. Also included is a complete listing of District and Illinois-related USGS publications.
This report gives an overview of U.S. Geological Survey, Illinois District, Water Resources Division activities related to the water resources of the State of Illinois. The report includes sections describing District organization, programs, water conditions, data collection activities, and project summaries. Also included is a complete listing of District and Illinois-related USGS publications.
Regional aquifers in the Mississippi embayment are the principal sources of water used for public and domestic supply, irrigation, and industrial uses throughout the region. An understanding of how water quality varies spatially, temporally, and with depth are critical aspects to ensuring long-term sustainable use of these resources. A boosted regression tree (BRT) model was used by the U.S. Geological Survey (USGS) to map water quality in the three regional aquifers with the largest groundwater withdrawals in the embayment: the Mississippi River Valley alluvial (MRVA) aquifer, middle Claiborne aquifer (MCAQ), and lower Claiborne aquifer (LCAQ). The BRT model was used to predict pH to 1-kilometer raster grid cells for seven aquifer layers (one MRVA, four MCAQ, two LCAQ) following the hydrogeologic framework of the Mississippi embayment aquifer system regional MODFLOW model. The methods and approach used for pH predictions are the same as those used recently by the USGS to predict specific conductance and chloride in the aquifers. Explanatory variables for the BRT models included variables describing well location and construction, surficial variables such as soil properties and land use, and variables extracted from the groundwater flow model, such as groundwater levels and ages. The primary source of pH data was the USGS National Water Information System database. Additional data from State ambient groundwater monitoring programs and the Safe Drinking Water Information System also were used. For wells sampled multiple times, the most recent sample was used. Because groundwater residence times are long (greater than 100 years) throughout much of the study area, the possible effects of changes in water quality over time were considered small compared to the improvement in overall model accuracy by using available historical data. Values of pH from 3,362 wells for samples collected between 1960 and 2018 were used as training data for the BRT model. An additional 839 samples were used as holdout data to evaluate model performance. The predictive performance of the pH model is lower than for the training dataset, as indicated by an r-squared value of 0.89 for the training data and an r-squared of 0.71 for the holdout data. The root mean squared errors for the training and holdout data are 0.32 and 0.50 standard pH units, respectively. Data generated during this study and the model output are available from the companion data release.
The potential for anthropogenic effects on ground water is becoming of increasing concern as land throughout the Nation becomes more urbanized. The possible contamination of water resources by volatile organic compounds (VOCs), pesticides (including transformation products), and nitrate, from current urban land use and past agricultural land use, is of particular concern. As part of the U.S. Geological Survey's National Water-Quality Assessment program, water samples for analysis of VOCs, pesticides, and nitrate were collected from 43 wells in shallow (175 feet deep or less) ground water in glacial deposits overlying a major bedrock aquifer in recently urbanized areas in the Chicago, Ill. and Milwaukee, Wis. metropolitan counties.Constituents were reported using two reporting levels. For the laboratory reporting level, the risk of a false positive or false negative detection is less than or equal to 1 percent. For the information-rich method level, estimated concentrations are identified positively and are qualified to be present on the basis of quality-control criteria, but have a higher risk of false positive detections.VOCs were detected in 32 percent (12 of 38) of the well samples with 15 detections of 7 VOCs, based on laboratory reporting levels. Concentrations ranged from 0.03 (estimated) to 4.6 micrograms per liter (?g/L), with a median concentration of 0.13 ?g/L. Methyl tert-butyl ether (MTBE) and trichloromethane (chloroform) were the most common with detections in 10 percent (4 of 38) of the well samples. Using information-rich method reporting levels, VOCs were detected in 74 percent of the wells with 37 detections of 15 VOCs. Chloroform was most common with detections in 24 percent (9 of 38) of the well samples.Pesticides were detected in 62 percent (26 of 42) of the well samples with 83 detections of 20 pesticides, based on laboratory reporting levels for the respective constituent. Concentrations ranged from 0.003 (estimated) to 3.6 (estimated) ?g/L, with a median concentration of 0.06 ?g/L. Deethylatrazine was most common with detections in 43 percent (18 of 42) of the well samples. Using information-rich method reporting levels, pesticides were detected in 74 percent (31 of 42) of the well samples with 134 detections of 29 pesticides. Deethylatrazine was most common with detections in 45 percent (19 of 42) of the well samples.Nitrate concentrations ranged from less than 0.047 to 12.5 milligrams per liter (mg/L) with a median concentration of 0.068 mg/L. Nitrate concentrations were greater than 2 mg/L in 30 percent (13 of 43) of the wells sampled. Total VOC detections did not correlate well (less than Spearman Rank correlation value of plus or minus 0.10) with well depth, age, or dissolved oxygen. Total pesticide detections did correlate with dissolved oxygen and negatively correlated with well depth. Nitrate concentrations correlated with dissolved oxygen and apparent recharge date.No VOC or pesticide concentrations exceeded U.S. Environmental Protection Agency drinking-water standards and only one nitrate 2 Anthropogenic Constituents in Shallow Ground Water in the Upper Illinois River Basin detection exceeded the standards. However, of the 43 wells sampled for VOCs or pesticides using information-rich methods, or nitrate at laboratory reporting levels, 40 of 43 (93 percent) well samples had at least one detection of a VOC or pesticide, or a detection of nitrate above 2.0 mg/L. This result indicates that most of these wells are anthropogenically affected, but presently not at U.S. Environmental Protection Agency drinking-water regulation levels of concern. The wells sampled were not public drinking-water supplies; therefore, these wells were not subject to U.S. Environmental Protection Agency drinking-water regulations.
Groundwater quality in the approximately 1,000-square-mile (2,590-square-kilometer) Upper Santa Ana Watershed (USAW) study unit was investigated as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The study unit is located in southern California in Riverside and San Bernardino Counties. The GAMA Priority Basin Project is being conducted by the California State Water Resources Control Board in collaboration with the U.S. Geological Survey and the Lawrence Livermore National Laboratory. The GAMA USAW study was designed to provide a spatially unbiased assessment of untreated groundwater quality within the primary aquifer systems in the study unit. The primary aquifer systems (hereinafter, primary aquifers) are defined as the perforation interval of wells listed in the California Department of Public Health (CDPH) database for the USAW study unit. The quality of groundwater in shallower or deeper water-bearing zones may differ from that in the primary aquifers; shallower groundwater may be more vulnerable to surficial contamination. The assessment is based on water-quality and ancillary data collected by the U.S. Geological Survey (USGS) from 90 wells during November 2006 through March 2007, and water-quality data from the CDPH database. The status of the current quality of the groundwater resource was assessed based on data from samples analyzed for volatile organic compounds (VOCs), pesticides, and naturally occurring inorganic constituents, such as major ions and trace elements. The status assessment is intended to characterize the quality of groundwater resources within the primary aquifers of the USAW study unit, not the treated drinking water delivered to consumers by water purveyors. Relative-concentrations (sample concentration divided by the health- or aesthetic-based benchmark concentration) were used for evaluating groundwater quality for those constituents that have Federal or California regulatory or non-regulatory benchmarks for drinking-water quality. A relative-concentration greater than (>) 1.0 indicates a concentration above a benchmark, and a relative-concentration less than or equal to (≤) 1.0 indicates a concentration equal to or less than a benchmark. Organic and special-interest constituent relative-concentrations were classified as "high" (> 1.0), "moderate" (0.1 < relative-concentration ≤ 1.0), or "low" (≤ 0.1). Inorganic constituent relative-concentrations were classified as "high" (> 1.0), "moderate" (0.5 < relative-concentration ≤ 1.0), or "low" ( ≤ 0.5). Aquifer-scale proportion was used as the primary metric in the status assessment for evaluating regional-scale groundwater quality. Aquifer-scale proportions are defined as the percentage of the area of the primary aquifer system with concentrations above or below specified thresholds relative to regulatory or aesthetic benchmarks. High aquifer-scale proportion is defined as the percentage of the area of the primary aquifers with a relative-concentration greater than 1.0 for a particular constituent or class of constituents; percentage is based on an areal, rather than a volumetric basis. Moderate and low aquifer-scale proportions were defined as the percentage of the primary aquifers with moderate and low relative-concentrations, respectively. Two statistical approaches—grid-based and spatially weighted—were used to evaluate aquifer-scale proportions for individual constituents and classes of constituents. Grid-based and spatially weighted estimates were comparable in the USAW study unit (within 90-percent confidence intervals). Inorganic constituents with human-health benchmarks had relative-concentrations that were high in 32.9 percent of the primary aquifers, moderate in 29.3 percent, and low in 37.8 percent. The high aquifer-scale proportion of these inorganic constituents primarily reflected high aquifer-scale proportions of nitrate (high relative-concentration in 25.3 percent of the aquifer), although seven other inorganic constituents with human-health benchmarks also were detected at high relative-concentrations in some percentage of the aquifer: arsenic, boron, fluoride, gross alpha activity, molybdenum, uranium, and vanadium. Perchlorate, as a constituent of special interest, was evaluated separately from other inorganic constituents, and had high relative-concentrations in 11.1 percent, moderate in 53.3 percent, and low or not detected in 35.6 percent of the primary aquifers. In contrast to the inorganic constituents, relative-concentrations of organic constituents (one or more) were high in 6.7 percent, moderate in 11.1 percent, and low or not detected in 82.2 percent of the primary aquifers. Of the 237 organic and special-interest constituents analyzed for, 39 constituents were detected (21 VOCs, 13 pesticides, 3 pharmaceuticals, and 2 constituents of special interest). All of the detected VOCs had health-based benchmarks, and five of these—1,1-dichloroethene, 1,2-dibromo-3-chloropropane (DBCP), tetrachloroethene (PCE), carbon tetrachloride, and trichloroethene (TCE)—were detected in at least one sample at a concentration above a benchmark (high relative-concentration). Seven of the 13 pesticides had health-based benchmarks, and none were detected above these benchmarks (no high relative-concentrations). Pharmaceuticals do not have health-based benchmarks. Thirteen organic constituents were frequently detected (detected in at least 10 percent of samples without regard to relative-concentrations): bromodichloromethane, chloroform, cis-1,2-dichloroethene, 1,1-dichloroethene, dichlorodifluoromethane (CFC-12), methyl tert-butyl ether (MTBE), PCE, TCE, trichlorofluoromethane (CFC-11), atrazine, bromacil, diuron, and simazine.
Product Information “Critter Tales: Adventures in Restoration Activity Book” is an interactive educational resource designed for children ages 5–9, produced by the U.S. Geological Survey in cooperation with the U.S. Department of the Interior, Office of Restoration and Damage Assessment. Through the journey of Lulu the loon and a cast of animal friends, young readers explore the importance of ecological restoration across diverse habitats—from sand dunes and wetlands to prairies and streams. The activity book blends storytelling, science, and hands-on activities to teach children how restoration efforts help wildlife thrive. Readers learn about native plants, animal life cycles, and the role of restoration in protecting habitats for birds, turtles, butterflies, mussels, and more. Engaging puzzles, coloring pages, and interactive challenges encourage kids to become nature’s helpers, fostering environmental stewardship and awareness. With vibrant illustrations and accessible language, the publication highlights practical actions—such as planting native milkweed, using lead-free fishing tackle, and supporting mussel restoration—that empower children to make a positive change in their own communities. The book also introduces basic ecological concepts and celebrates the interconnectedness of living things, making it an ideal resource for families, educators, and anyone interested in environmental education.
Elevation data are essential to a broad range of applications, including forest resources management, wildlife and habitat management, national security, recreation, and many others. For the State of Idaho, elevation data are critical for agriculture and precision farming, natural resources conservation, infrastructure and construction management, geologic resource assessment and hazard mitigation, flood risk management, forest resources management, and other business uses. Today, high-quality light detection and ranging (lidar) data are the sources for creating elevation models and other elevation datasets. Federal, State, and local agencies work in partnership to (1) replace data, on a national basis, that are (on average) 30 years old and of lower quality and (2) provide coverage where publicly accessible data do not exist. A joint goal of State and Federal partners is to acquire consistent, statewide coverage to support existing and emerging applications enabled by lidar data. The new 3D Elevation Program (3DEP) initiative, managed by the U.S. Geological Survey (USGS), responds to the growing need for high-quality topographic data and a wide range of other three-dimensional representations of the Nation’s natural and constructed features. The Idaho LiDAR Consortium provides statewide collaboration and data sharing mechanisms that can be used as a resource by State and Federal partners implementing the 3DEP initiative.
The investigation of the ground-water resources of Santa Barbara County was continued (luring 1954 in cooperation with the Santa Barbara County Wallet Agency. Monthly water-level measurements were made in 182 wells in 6 of which automatic water-level recorders were operated. Earlier measurements covering the period 1941 through 1952 have been published in U. S. Geological Survey water-supply papers; those for 1953 are in press and have already been released locally in duplicated form. Water-Supply Paper 1068 contains tabulated descriptions for 2,246 wells in existence in 1942 in the various ground-water basins of the county. The same publication contains also many water-level measurements made prior to 1942 by the city of Santa Barbara, Santa Maria Valley Water Conservation District, San Joaquin Power Division of the Pacific GAB and Electric Co., Union Sugar Co., Union Oil Co., and other organizations and individuals. Comprehensive reports on the geology and ground-water resources of the Santa Time River basin (Upson and Thomasson, 1951), the south-coast basins (Upson, 1951), the Santa Maria Valley area (Worts, 1951), and the Cuyama Valley (Upson and Worts, 1951) have been published as Water-Supply Papers 1107, 1108 100U. and 1110-B respectively. In October 1952 "Reports on stream runoff and ground-water storage capacity, Santa Ynez River, Santa Barbara Count, Calif.," prepared respectively by Messrs. H. C. Troxell of the Surface Water Branch and H. D. Wilson, Jr., of the Ground hater Branch, U. S. Geological Survey, were released (Troxell and Wilson, 1952). In 1954 water-level measurements were made by the city of Santa Maria and the Santa Maria Valley Water Conservation District, in addition to those made by the Geological Survey, and are included in this report.
This report details the findings of the Bureau of Land Management–U.S. Geological Survey Ecosystem Services Valuation Pilot Study. This project evaluated alternative methods and tools that quantify and value ecosystem services, and it assessed the tools’ readiness for use in the Bureau of Land Management decisionmaking process. We tested these tools on the San Pedro River watershed in northern Sonora, Mexico, and southeast Arizona. The study area includes the San Pedro Riparian National Conservation Area (managed by the Bureau of Land Management), which has been a focal point for conservation activities and scientific research in recent decades. We applied past site-specific primary valuation studies, value transfer, the Wildlife Habitat Benefits Estimation Toolkit, and the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) and Artificial Intelligence for Ecosystem Services (ARIES) models to value locally important ecosystem services for the San Pedro River watershed—water, carbon, biodiversity, and cultural values. We tested these approaches on a series of scenarios to evaluate ecosystem service changes and the ability of the tools to accommodate scenarios. A suite of additional tools were either at too early a stage of development to run, were proprietary, or were place-specific tools inappropriate for application to the San Pedro River watershed. We described the strengths and weaknesses of these additional ecosystem service tools against a series of evaluative criteria related to their usefulness for Bureau of Land Management decisionmaking. Using these tools, we quantified gains or losses of ecosystem services under three categories of scenarios: urban growth, mesquite management, and water augmentation. These results quantify tradeoffs and could be useful for decisionmaking within Bureau of Land Management district or field offices. Results are accompanied by a relatively high level of uncertainty associated with model outputs, valuation methods, and discount rates applied. Further guidance on representing uncertainty and applying uncertain results in decisionmaking would benefit both tool developers and those offices in using ecosystem services to compare management tradeoffs. Decisionmakers and Bureau of Land Management managers at the State-, district-, and field-office level would also benefit from continuing model improvements, training, and guidance on tool use that can be provided by the U.S. Geological Survey, the Bureau of Land Management, and the Department of the Interior. Tradeoffs were identified in the level of effort needed to parameterize and run tools and the amount and quality of information they provide to the decision process. We found the Wildlife Habitat Benefits Estimation Toolkit, Ecosystem Services Review, and United Nations Environment Programme–World Conservation Monitoring Centre Ecosystem Services Toolkit to be immediately feasible for application by the Bureau of Land Management, given proper guidance on their use. It is also feasible for the Bureau of Land Management to use the InVEST model, but in early 2012 the process of parameterizing the model required resources and expertise that are unlikely to be available in most Bureau of Land Management district or field offices. Application of past primary valuation is feasible, but developing new primary-valuation studies is too time consuming for regular application. Value transfer approaches (aside from the Wildlife Habitat Benefits Estimation Toolkit) are best applied carefully on the basis of guidelines described in this report, to reduce transfer error. The ARIES model can provide useful information in regions modeled in the past (Arizona, California, Colorado, and Washington), but it lacks some features that will improve its usability, such as a generalized model that could be applied anywhere in the United States. Eleven other tools described in this report could become useful as the tools more fully develop, in high-profile cases for which additional resources are available for tool application or in case-study regions where place-specific models have already been developed. To improve the value of these tools in decisionmaking, we suggest scientific needs that agencies such as U.S. Geological Survey can help meet—for instance, development and support of data archives. Such archives could greatly reduce resource needs and improve the reliability and consistency of results. Given the rapid state of evolution in the field, periodic follow-up studies on ecosystem services tools would help to ensure that the Bureau of Land Management and other public land management agencies are kept up to date on new tools and features that bring ecosystem services closer to readiness for use in regular decisionmaking.
Groundwater quality in the approximately 860-square-mile (2,227-square-kilometer) Coastal Los Angeles Basin study unit (CLAB) was investigated as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The study area is located in southern California in Los Angeles and Orange Counties. The GAMA Priority Basin Project is being conducted by the California State Water Resources Control Board in collaboration with the U.S. Geological Survey (USGS) and the Lawrence Livermore National Laboratory. The GAMA CLAB study was designed to provide a spatially unbiased assessment of the quality of untreated (raw) groundwater in the primary aquifer system. The assessment is based on water-quality and ancillary data collected in 2006 by the USGS from 69 wells and on water-quality data from the California Department of Public Health (CDPH) database. The primary aquifer system was defined by the depth interval of the wells listed in the CDPH database for the CLAB study unit. The quality of groundwater in the primary aquifer system may be different from that in the shallower or deeper water-bearing zones; shallow groundwater may be more vulnerable to surficial contamination. This study assesses the status of the current quality of the groundwater resource by using data from samples analyzed for volatile organic compounds (VOCs), pesticides, and naturally occurring inorganic constituents, such as major ions and trace elements. This status assessment is intended to characterize the quality of groundwater resources in the primary aquifer system of the CLAB study unit, not the treated drinking water delivered to consumers by water purveyors. Relative-concentrations (sample concentration divided by the health- or aesthetic-based benchmark concentration) were used for evaluating groundwater quality for those constituents that have Federal and (or) California regulatory or non-regulatory benchmarks for drinking-water quality. A relative-concentration greater than (>) 1.0 indicates a concentration greater than a benchmark, and a relative-concentration less than or equal to (≤) 1.0 indicates a concentration equal to or less than a benchmark. Relative-concentrations of organic and special-interest constituents [perchlorate, N -nitrosodimethylamine (NDMA), 1,2,3-trichloropropane (1,2,3-TCP), and 1,4-dioxane] were classified as "high" (relative-concentration>1.0), "moderate" (0.5 status assessment for evaluating regional-scale groundwater quality. High aquifer-scale proportion is defined as the percentage of the area of the primary aquifer system with a relative-concentration greater than 1.0 for a particular constituent or class of constituents; percentage is based on an areal rather than a volumetric basis. Moderate and low aquifer-scale proportions were defined as the percentage of the primary aquifer system with moderate and low relative-concentrations, respectively. Two statistical approaches-grid-based and spatially weighted-were used to evaluate aquifer-scale proportions for individual constituents and classes of constituents. Grid-based and spatially weighted estimates were comparable in the CLAB study unit (within 90-percent confidence intervals). Inorganic constituents with human-health benchmarks were detected at high relative-concentrations in 5.6 percent of the primary aquifer system and moderate in 26 percent. High aquifer-scale proportion of inorganic constituents primarily reflected high aquifer-scale proportions of arsenic (1.9 percent), nitrate (1.9 percent), and uranium (1.2 percent). Inorganic constituents with secondary maximum contaminant levels (SMCL) were detected at high relative-concentrations in 18 percent of the primary aquifer system and moderate in 47 percent. The constituents present at high relative-concentrations included total dissolved solids (1.9 percent), manganese (15 percent), and iron (9.4 percent). Relative-concentrations of organic constituents (one or more) were high in 3.7 percent, and moderate in 13 percent, of the primary aquifer system. The high aquifer-scale proportion of organic constituents primarily reflected high aquifer-scale proportions of solvents, including trichloroethene (TCE; 1.7 percent), perchloroethene (PCE; 1.1 percent), and carbon tetrachloride (1.0 percent). Of the 204 organic constituents analyzed, 44 constituents were detected. Eleven organic constituents had detection frequencies of greater than 10 percent: the trihalomethanes chloroform and bromodichloromethane, the solvents TCE, PCE, cis -1,2-dichloroethene, and 1,1-dichloroethene, the herbicides atrazine, simazine, prometon, and tebuthiuron, and the gasoline additive methyl tert -butyl ether (MTBE). Most detections were at low relative-concentrations. The special-interest constituent perchlorate was detected at high relative-concentrations in 0.5 percent of the primary aquifer system, and at moderate relative-concentrations in 35 percent. The special-interest constituent 1,4-dioxane was detected at high relative-concentrations, but an insufficient number of samples was analyzed to provide a representative estimate of aquifer-scale proportion.
This fact sheet highlights findings from the vulnerability study of a public-supply well field in San Antonio, Texas. The well field consists of six production wells that tap the Edwards aquifer. Typically, one or two wells are pumped at a time, yielding an average total of 20-21 million gallons per day. Water samples were collected from public-supply wells in the well field and from monitoring wells installed along general directions of flow to the well field. Samples from the well field contained some constituents of concern for drinking-water quality, including nitrate; the pesticide compounds atrazine, deethylatrazine, and simazine; and the volatile organic compounds tetrachloroethene (also called perchloroethene, or PCE), chloroform, bromoform, and dibromochloromethane. These constituents were detected in untreated water at concentrations much less than established drinking-water standards, where such standards exist. Overall, the study findings point to four primary factors that affect the movement and fate of contaminants and the vulnerability of the public-supply well field in San Antonio, Texas: (1) groundwater age (how long ago water entered, or recharged, the aquifer), (2) fast pathways for flow of groundwater through features formed or enlarged by dissolution of bedrock, (3) recharge characteristics of the aquifer, and (4) natural geochemical processes within the aquifer. A computer-model simulation of groundwater flow and transport was used to estimate the traveltime (or age) of water particles entering public-supply well W4 in the well field. Modeled findings show that almost half of the water reaching the public-supply well is less than 2 years old. Such a large percentage of very young water indicates that (1) contaminants entering the aquifer may be transported rapidly to the well, (2) there is limited time for chemical reactions to occur in the aquifer that may attenuate contaminants, and (3) should recharge water become contaminated with pathogenic microorganisms (which have limited survival times in aquifers), the microorganisms may be able to persist to the well. Features formed or enlarged by dissolution of bedrock allow most of the water reaching the well field to travel rapidly from the recharge zone to the supply wells along fast pathways rather than through the aquifer matrix. Supporting evidence includes (1) geophysical logging and flowmeter measurements in public-supply well W4 and in nearby monitoring wells showing that most of the flow volume into and out of the wells occurs in three horizontal zones, thought to be dissolution-enlarged bedding planes; and (2) fluctuations in groundwater chemistry that can be correlated to individual precipitation events. Analysis of water samples collected from shallow, intermediate, and deep zones of the Edwards aquifer at public-supply well W4 and from nearby monitoring wells reveal that water in the vicinity of the selected well field is notably well mixed throughout the sampled thickness of the Edwards aquifer, showing little of the chemical variation with depth that is commonly seen in other aquifers. Contaminants were found at all depths, and they did not enter the well through a specific horizon. The well-mixed nature of the Edwards aquifer is caused by the recharge characteristics of the area combined with fast flow paths through karst features. Constituents of concern in the Edwards aquifer for the long-term sustainability of the groundwater resource include the nutrient nitrate and anthropogenic contaminants such as atrazine, PCE, and chloroform. A scenario of hypothetical contaminant loading in the aquifer recharge zone was evaluated by using results from groundwater-flow-model particle tracking to assess the response of the aquifer to potential contamination. Results indicate that the concentrations at public-supply well W4 would begin to respond to contaminant loading in the recharge zone within 1 year because of short traveltimes through fast flow paths. Within 10 years, contaminant concentrations in the public-supply well would be equal to 90 percent of the input concentration for a contaminant (such as nitrate) that does not degrade in the oxic conditions of the Edwards aquifer.
Investigation of the ground-water resources of Santa Barbara County was continued during 1958 by the U. S. Geological Survey in cooperation with the Santa Barbara County Water Agency. Monthly water-level measurements were made in 201 wells, in 11 of which automatic water-level recorders were operated. Earlier measurements, covering the period 1941 through 1955, have been published in Geological Survey Water-Supply Papers; those for 1956 and 1957 have been released locally in duplicated form. Water-Supply Paper 1068 contains tabulated descriptions of 2,246 wells in existence in 1942 in the various ground-water basins of the county. The same publication also contains many water-level measurements made prior to 1942 by the city of Santa Barbara, Santa Maria Valley Water Conservation District, San Joaquin Power Division of the Pacific Gas and Electric Co., Union Sugar Co., Union Oil Co., and other organizations and individuals. Comprehensive reports on the geology and ground-water resources of the Santa Ynez River basin (Upson and Thomasson, 1951), the south-coast basins (Upson, 1951), the Santa Maria Valley area (Worts, 1951), and the Cuyama Valley (Upson and Worts, 1951) have been published as Water-Supply Papers 1107, 1108, 1000, and 1110-B, respectively. A report on stream runoff and ground-water storage capacity of the Santa Ynez River valley (Troxell and Wilson, 1952) was released to the open file in October 1952. A report appraising the ground-water resources of the Santa Ynez River valley (Wilson, 1957) has been mimeographed and released locally. In addition to the water-level measurements made by the Geological Survey in 1958, measurements made by the Santa Maria Valley Water Conservation District are included in this report. Not included in this report are miscellaneous measurements made by the Geological Survey in wells along the middle reach of the Santa Ynez River between Cachuma Dam and Rucker Crossing.
The quality of water accessed by domestic wells (here referred to as domestic groundwater resources) in the San Joaquin Valley Kern County subbasin (basin number 5-022.14) was assessed as part of the California Groundwater Ambient Monitoring and Assessment (GAMA) Program Priority Basin Project (GAMA-PBP), in cooperation with the California State Water Resources Control Board. Kern County is at the southern end of the San Joaquin Valley in California, and about 30,000 residents are estimated to use privately owned domestic wells for drinking water. Domestic wells typically draw from shallower parts of the aquifer system than public-supply wells and can be more vulnerable to effects from surface activities. Kern County is host to a highly productive agricultural industry, with Bakersfield as the main urban center. The Kern River runs through Bakersfield from the southern Sierra Nevada and intersects the Kern Water Bank, one of the largest groundwater banking operations in California, at the Kern River Intertie. The section of the Kern River running through the Kern Water Bank is dry most years. Kern County also encompasses some of the most productive oil and gas basins in California, with extensive underground and surface disposal of oil-field wastewater. This study was based on data collected from 33 sites sampled by the U.S. Geological Survey for the GAMA-PBP in 2022. To provide context for the water quality assessment, measured concentrations were compared to regulatory and non-regulatory health-based and aesthetic benchmarks. A grid-based method was used to estimate the proportions of the groundwater resources used for domestic-supply wells that have water-quality constituents below (low relative concentration), approaching (moderate relative concentration), or above (high relative concentration) benchmark concentrations. At least one measured constituent with a regulatory benchmark was categorized as having a high relative concentration in 72 percent of the aquifer area used for domestic groundwater resources. Inorganic constituents were detected at high concentrations in 45 percent of the domestic groundwater resources, and the constituents detected above regulatory benchmarks were arsenic, nitrate, and uranium. At least one organic constituent was detected at high concentrations in 41 percent of the domestic groundwater resources, and the constituents exceeding regulatory benchmarks were the fumigants 1,2,3-trichloropropane (1,2,3-TCP), 1,2-dibromo-3-chloropropane (dibromochloropropane [DBCP]), 1,2-dibromoethane (EDB), and the per-and polyfluoroalkyl substance (PFAS) perfluorooctanesulfonate. The disinfection by-product chloroform, the fumigant 1,2-dichloropropane, the herbicides atrazine and hexazinone, and the herbicide degradates 2-chloro-6-ethylamino-4-amino-s-triazine, 2-chloro-4,6-diamino-s-triazine, 4-hydroxychlorothalonil, and metolachlor sulfonic acid were detected in more than 10 percent of domestic groundwater resources, but concentrations did not exceed regulatory benchmarks. Land use, groundwater age (fraction of modern water and mean age), and geochemical environment (oxic or anoxic conditions, pH, alkalinity) were associated with the distribution of high relative concentrations of inorganic and organic constituents. Young, oxygenated water is recharged along the Kern River and adjacent recharge ponds, or as irrigation water in the agricultural areas. High concentrations of nitrate and volatile organic compounds occurred in the oxic water in urban and agricultural areas. The fumigants 1,2,3-TCP, DBCP, and EDB were reported throughout the agricultural areas, whereas chloroform, tetrachloroethene, and PFAS were associated with urban land use. High uranium concentrations were associated with young, modern groundwater in agricultural areas with low pH and high bicarbonate. Total dissolved solids increased with distance from the Kern River, as the contributions of fresh, oxic water decreased. High concentrations of arsenic were present in older anoxic or alkaline groundwater away from areas of recharge. Overall, groundwater age, redox conditions, and the source of recharge as a result of different land uses contribute to large aquifer-scale portions of domestic groundwater resources that exceed health-based benchmarks for nitrate, uranium, and fumigant concentrations.
Investigation of the ground-water resources of Santa Barbara County was continued during 1959 by the U. S. Geological Survey in cooperation with the Santa Barbara County Water Agency. Monthly water-level measurements were made in 203 wells, in 8 of which automatic water-level recorders were operated. Earlier measurements, covering the period 1941 through 1955, have been published in Geological Survey Water-Supply Papers; those for 1956, 1957, and 1958 have been released locally in duplicated form. Water-Supply Paper 1068 contains tabulated descriptions of 2,246 wells in existence in 1942 in the various ground-water basins of the county. The same publication also contains many water-level measurements made prior to 1942 by the city of Santa Barbara, Santa Maria Valley Water Conservation District, San Joaquin Power Division of the Pacific Gas and Electric Co., Union Sugar Co., Union Oil Co., and other organizations and individuals. Comprehensive reports on the geology and ground-water resources of the Santa Ynez River basin (Upson and Thomasson, 1951, and Wilson, 1959), the south-coast basins (Upson, 1951), the Santa Maria Valley area (Worts, 1951), and the Cuyama Valley (Upson and Worts, 1951) have been published as Water-Supply Papers 1107, 1467, 1108, 1000, and 1110-B, respectively. A report on stream runoff and ground-water storage capacity of the Santa Ynez River valley (Troxell and Wilson, 1952) was released to the open file in October 1952. In addition to the water-level measurements made by the Geological Survey in 1959, measurements made by the Santa Maria Valley Water Conservation District are included in this report. Not included in this report are miscellaneous measurements made by the Geological Survey in wells along the middle reach of the Santa Ynez River between Cachuma Dam and Rucker Crossing.
Malaria is a major global public health problem, particularly in Sub-Saharan Africa. The spatial heterogeneity of malaria can be affected by factors such as hydrological processes, physiography, and land cover patterns. Tropical wetlands, for example, are important hydrological features that can serve as mosquito breeding habitats. Mapping and monitoring of wetlands using satellite remote sensing can thus help to target interventions aimed at reducing malaria transmission. The objective of this study was to map wetlands and other major land cover types in the Amhara region of Ethiopia and to analyze district-level associations of malaria and wetlands across the region. We evaluated three random forests classification models using remotely sensed topographic and spectral data based on Shuttle Radar Topographic Mission (SRTM) and Landsat TM/ETM+ imagery, respectively. The model that integrated data from both sensors yielded more accurate land cover classification than single-sensor models. The resulting map of wetlands and other major land cover classes had an overall accuracy of 93.5%. Topographic indices and subpixel level fractional cover indices contributed most strongly to the land cover classification. Further, we found strong spatial associations of percent area of wetlands with malaria cases at the district level across the dry, wet, and fall seasons. Overall, our study provided the most extensive map of wetlands for the Amhara region and documented spatiotemporal associations of wetlands and malaria risk at a broad regional level. These findings can assist public health personnel in developing strategies to effectively control and eliminate malaria in the region.
Expert forecasts of worldwide water scarcity depict conditions that call for proactive, preventive, coordinated water governance, but they have not been matched by public agendas of commensurate scope and urgency in the United States. This disconnect can not be adequately explained without some attention to attributes of forecasts themselves. I propose that the institutional fragmentation of water expertise and prevailing patterns of communication about water scarcity militate against the formulation of a common public definition of the problem and encourage reliance on unambiguous crises to stimulate social and policy agenda setting. I do not argue that expert forecasts should drive public agendas deterministically, but if their purpose is to help prevent water crises (not just predict them), then a greater effort is needed to overcome the barriers to meaningful public scrutiny of expert claims and evaluation of water strategies presently in place. Copyright ?? 2006 Taylor & Francis Group, LLC.
Recent advances in atmospheric sciences and hydrology have identified the key role of atmo-spheric rivers (ARs) in determining the distribution of strong precipitation events in the midlatitudes. The growth of the subject is evident in the increase in scientific publications that discuss ARs (Fig. 1a). Combined with related phenomena, that is, warm conveyor belts (WCBs) and tropical moisture exports (TMEs), the frequency, position, and strength of ARs determine the occurrence of floods, droughts, and water resources in many parts of the world. A conference at the Scripps Institution of Oceanography in La Jolla, California, recently gathered over 100 experts in atmospheric, hydrologic, oceanic, and polar science; ecology; water management; and civil engineering to assess the state of AR science and to explore the need for new information. This first International Atmospheric Rivers Conference (IARC) allowed for much needed introductions and interactions across fields and regions, for example, participants came from five continents, and studies covered ARs in six continents and Greenland (Fig. 1b). IARC also fostered discussions of the status and future of AR science, and attendees strongly supported the idea of holding another IARC at the Scripps Institution of Oceanography in the summer of 2018.