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At least 1,045 records · Page 58Linked to original sources
USGS2007

Evaluation of Approaches for Managing Nitrate Loading from On-Site Wastewater Systems near La Pine, Oregon

This report presents the results of a study by the U.S. Geological Survey, done in cooperation with the Oregon Department of Environmental Quality and Deschutes County, to develop a better understanding of the effects of nitrogen from on-site wastewater disposal systems on the quality of ground water near La Pine in southern Deschutes County and northern Klamath County, Oregon. Simulation models were used to test the conceptual understanding of the system and were coupled with optimization methods to develop the Nitrate Loading Management Model, a decision-support tool that can be used to efficiently evaluate alternative approaches for managing nitrate loading from on-site wastewater systems. The conceptual model of the system is based on geologic, hydrologic, and geochemical data collected for this study, as well as previous hydrogeologic and water quality studies and field testing of on-site wastewater systems in the area by other agencies. On-site wastewater systems are the only significant source of anthropogenic nitrogen to shallow ground water in the study area. Between 1960 and 2005 estimated nitrate loading from on-site wastewater systems increased from 3,900 to 91,000 pounds of nitrogen per year. When all remaining lots are developed (in 2019 at current building rates), nitrate loading is projected to reach nearly 150,000 pounds of nitrogen per year. Low recharge rates (2-3 inches per year) and ground-water flow velocities generally have limited the extent of nitrate occurrence to discrete plumes within 20-30 feet of the water table; however, hydraulic-gradient and age data indicate that, given sufficient time and additional loading, nitrate will migrate to depths where many domestic wells currently obtain water. In 2000, nitrate concentrations greater than 4 milligrams nitrogen per liter (mg N/L) were detected in 10 percent of domestic wells sampled by Oregon Department of Environmental Quality. Numerical simulation models were constructed at transect (2.4 square miles) and study-area (247 square miles) scales to test the conceptual model and evaluate processes controlling nitrate concentrations in ground water and potential ground-water discharge of nitrate to streams. Simulation of water-quality conditions for a projected future build-out (base) scenario in which all existing lots are developed using conventional on-site wastewater systems indicates that, at equilibrium, average nitrate concentrations near the water table will exceed 10 mg N/L over areas totaling 9,400 acres. Other scenarios were simulated where future nitrate loading was reduced using advanced treatment on-site systems and a development transfer program. Seven other scenarios were simulated with total nitrate loading reductions ranging from 15 to 94 percent; simulated reductions in the area where average nitrate concentrations near the water table exceed 10 mg N/L range from 22 to 99 percent at equilibrium. Simulations also show that the ground-water system responds slowly to changes in nitrate loading due to low recharge rates and ground-water flow velocity. Consequently, reductions in nitrate loading will not immediately reduce average nitrate concentrations and the average concentration in the aquifer will continue to increase for 25-50 years depending on the level and timing of loading reduction. The capacity of the ground-water system to receive on-site wastewater system effluent, which is related to the density of homes, presence of upgradient residential development, ground-water recharge rate, ground-water flow velocity, and thickness of the oxic part of the aquifer, varies within the study area. Optimization capability was added to the study-area simulation model and the combined simulation-optimization model was used to evaluate alternative approaches to management of nitrate loading from on-site wastewater systems to the shallow alluvial aquifer. The Nitrate Loading Management Model (NLMM) was formulated to find the minimum red

Scientific Investigations Report↗
USGS2007

Environmental geochemical study of Red Mountain--an undisturbed volcanogenic massive sulfide deposit in the Bonnifield District, Alaska range, east-central Alaska: Chapter I in Recent U.S. Geological Survey studies in the Tintina Gold Province, Alaska, United States, and Yukon, Canada--results of a 5-year project

The Red Mountain volcanogenic massive sulfide (VMS) deposit exhibits well-constrained examples of acid-generating, metal-leaching, metal-precipitation, and self-mitigation (via co-precipitation, dilution, and neutralization) processes that occur in an undisturbed natural setting, a rare occurrence in North America. The unmined pyrite-rich deposit displays a remarkable environmental footprint of natural acid generation, high metal concentrations, and exceedingly high rare-earth-element (REE) concentrations in surface waters. Dissolution of pyrite and associated secondary reactions under near-surface, oxidizing conditions are the primary causes for the acid generation and metal leaching. The deposit is hosted in Devonian to Mississippian felsic metavolcanic rocks of the Mystic Creek Member of the Totatlanika Schist. Water samples with the lowest pH values, highest specific conductances, and highest major- and trace-element concentrations are from springs and streams within the quartz-sericite-pyrite alteration zone. Aluminum, As, Cd, Co, Cu, Fe, Mn, Ni, Pb, Y, and particularly Zn and the REEs are all found in high concentrations, ranging across four orders of magnitude. Waters collected upstream from the alteration zone have near-neutral pH values, lower specific conductances, lower metal concentrations, and measurable alkalinities. Water samples collected downstream of the alteration zone have pH values and metal concentrations intermediate between these two extremes. Stream sediments are anomalous in Zn, Pb, S, Fe, Cu, As, Co, Sb, and Cd relative to local and regional background abundances. Red Mountain Creek and its tributaries do not support, and probably never have supported, significant megascopic faunal aquatic life.

Alaska;Yukon↗
USGS2012

A new basaltic glass microanalytical reference material for multiple techniques

The U.S. Geological Survey (USGS) has been producing reference materials since the 1950s. Over 50 materials have been developed to cover bulk rock, sediment, and soils for the geological community. These materials are used globally in geochemistry, environmental, and analytical laboratories that perform bulk chemistry and/or microanalysis for instrument calibration and quality assurance testing. To answer the growing demand for higher spatial resolution and sensitivity, there is a need to create a new generation of microanalytical reference materials suitable for a variety of techniques, such as scanning electron microscopy/X-ray spectrometry (SEM/EDS), electron probe microanalysis (EPMA), laser ablation inductively coupled mass spectrometry (LA-ICP-MS), and secondary ion mass spectrometry (SIMS). As such, the microanalytical reference material (MRM) needs to be stable under the beam, be homogeneous at scales of better than 10–25 micrometers for the major to ultra-trace element level, and contain all of the analytes (elements or isotopes) of interest. Previous development of basaltic glasses intended for LA-ICP-MS has resulted in a synthetic basaltic matrix series of glasses (USGS GS-series) and a natural basalt series of glasses (BCR-1G, BHVO-2G, and NKT-1G). These materials have been useful for the LA-ICP-MS community but were not originally intended for use by the electron or ion beam community. A material developed from start to finish with intended use in multiple microanalytical instruments would be useful for inter-laboratory and inter-instrument platform comparisons. This article summarizes the experiments undertaken to produce a basalt glass reference material suitable for distribution as a multiple-technique round robin material. The goal of the analytical work presented here is to demonstrate that the elemental homogeneity of the new glass is acceptable for its use as a reference material. Because the round robin exercise is still underway, only nominal compositional ranges for each element are given in the article.

Microscopy Today↗
USGS2014

Integrating disparate lidar data at the national scale to assess the relationships between height above ground, land cover and ecoregions

With the acquisition of lidar data for over 30 percent of the US, it is now possible to assess the three-dimensional distribution of features at the national scale. This paper integrates over 350 billion lidar points from 28 disparate datasets into a national-scale database and evaluates if height above ground is an important variable in the context of other nationalscale layers, such as the US Geological Survey National Land Cover Database and the US Environmental Protection Agency ecoregions maps. While the results were not homoscedastic and the available data did not allow for a complete height census in any of the classes, it does appear that where lidar data were used, there were detectable differences in heights among many of these national classification schemes. This study supports the hypothesis that there were real, detectable differences in heights in certain national-scale classification schemes, despite height not being a variable used in any of the classification routines.

Photogrammetric Engineering and Remote Sensing↗
USGS2025

Assessment of natural gas pipeline construction on stream temperature and turbidity in southwestern Virginia, 2017—25

The natural gas pipeline network in the United States is extensive and often intersects streams and other sensitive habitats, yet there are limited case studies utilizing a comparative upstream-downstream approach to evaluate potential short- and long-term effects of pipeline stream crossing construction from pre-construction to post-site restoration. In 2017, the U.S. Geological Survey, in cooperation with the Virginia Department of Environmental Quality (DEQ), deployed real-time continuous stream monitoring stations upstream and downstream of six proposed Mountain Valley Pipeline (MVP) stream crossings in southwestern Virginia. Water temperature and turbidity data collected at the upstream and downstream sites were compared across three periods – before crossing construction, during crossing construction, and after crossing construction – to elucidate potential impacts from the stream crossing construction. Additionally, the monitoring network was utilized to notify regulators of potentially anomalous conditions throughout the entire monitoring period. Results of this study indicate (1) at all six monitored streams, pipeline stream crossing construction did not affect long-term or short-term upstream-to-downstream water temperature conditions; (2) pipeline stream crossing construction did not affect long-term upstream-to-downstream turbidity conditions in all six monitored streams. Some short-term anomalously elevated turbidity conditions were observed and attributable to pipeline stream crossing construction; however, the duration and magnitude were not sufficient to alter the long-term turbidity regime of the streams in which they were observed; and (3) the application of the monitoring network as a real-time alert system successfully alerted regulators to potentially anomalous conditions.

EarthArXiv↗
USGS2007

Characterization of flood sediments from Hurricanes Katrina and Rita and potential implications for human health and the environment

The flooding in the greater New Orleans, La., area that resulted from Hurricanes Katrina and Rita in August and September 2005 left behind accumulations of sediments up to many centimeters thick on streets, lawns, parking lots, and other flat surfaces (fig. 1). During the flood dewatering and subsequent cleanup, there were concerns that these sediments might contain pathogens and chemical contaminants that would pose a health risk to emergency responders, cleanup workers, and local residents who came into contact with the wet sediments or inhaled dusts generated from dried sediments. In response to these concerns, U.S. Geological Survey (USGS) scientists and colleagues characterized the potential environmental and health hazards of hurricane flood sediments from the greater New Orleans and Slidell, La., area.

Louisiana↗
USGS1981

Assessment of impacts of proposed coal-resource and related economic development on water resources, Yampa River basin, Colorado and Wyoming: A summary

Expanded mining and use of coal resources in the Rocky Mountain region of the western United States will have substantial impacts on water resources, environmental amenities, and social and economic conditions. The U.S. Geological Survey has completed a 3-year assessment of the Yampa River basin, Colorado and Wyoming, where increased coal-resource development has begun to affect the environment and quality of life. Economic projections of the overall effects of coal-resource development were used to estimate water use and the types and amounts of waste residuals that need to be assimilated into the environment. Based in part upon these projections, several physical-based models and other semiquantitative assessment methods were used to determine possible effects upon the basin's water resources. Depending on the magnitude of mining and use of coal resources in the basin, an estimated 0.7 to 2.7 million tons (0.6 to 2.4 million metric tons) of waste residuals may be discharged annually into the environment by coal-resource development and associated economic activities. If the assumed development of coal resources in the basin occurs, annual consumptive use of water, which was approximately 142,000 acre-feet (175 million cubic meters) during 1975, may almost double by 1990. In a related analysis of alternative cooling systems for coal-conversion facilities, four to five times as much water may be used consumptively in a wet-tower, cooling-pond recycling system as in once-through cooling. An equivalent amount of coal transported by slurry pipeline would require about one-third the water used consumptively by once-through cooling for in-basin conversion. Current conditions and a variety of possible changes in the water resources of the basin resulting from coal-resource development were assessed. Basin population may increase by as much as threefold between 1975 and 1990. Volumes of wastes requiring treatment will increase accordingly. Potential problems associated with ammonia-nitrogen concentrations in the Yampa River downstream from Steamboat Springs were evaluated using a waste-load assimilative-capacity model. Changes in sediment loads carried by streams due to increased coal mining and construction of roads and buildings may be apparent only locally; projected increases in sediment loads relative to historic loads from the basin are estimated to be 2 to 7 percent. Solid-waste residuals generated by coal-conversion processes and disposed of into old mine pits may cause widely dispersed ground-water contamination, based on simulation-modeling results. Projected increases in year-round water use will probably result in the construction of several proposed reservoirs. Current seasonal patterns of streamflow and of dissolvedsolids concentrations in streamflow will be altered appreciably by these reservoirs. Decreases in time-weighted mean-annual dissolved-solids concentrations of as much as 34 percent are anticipated, based upon model simulations of several configurations of proposed reservoirs. Detailed statistical analyses of water-quality conditions in the Yampa River basin were made. Regionalized maximum waterquality concentrations were estimated for possible comparison with future conditions. Using Landsat imagery and aerial photographs, potential remote-sensing applications were evaluated to monitor land-use changes and to assess both snow cover and turbidity levels in streams. The technical information provided by the several studies of the Yampa River basin assessment should be useful to regional planners and resource managers in evaluating the possible impacts of development on the basin's water resources.

Colorado, Wyoming↗
USGS2016

Toxicity of bed sediments from the Niagara River Area of Concern and tributaries, New York, to Chironomus dilutus and Hyalella azteca , 2014-15

The Niagara River was designated as an Area of Concern in 1987 on both the United States and Canadian sides of the international boundary line because past industrial discharges and hazardous waste sites had caused extensive degradation of aquatic habitats. The degradation of the “benthos”, or the benthic macroinvertebrate community, was identified as one of seven beneficial use impairments caused by contaminated bed sediments. The U.S. Geological Survey and the New York State Department of Environmental Conservation, in cooperation with the U.S. Environmental Protection Agency, conducted a study in 2014 and 2015 to gather more extensive data on (a) the toxicity of bed sediments and (b) the status of macroinvertebrate communities on the main stem and tributaries of the Niagara River. This report addresses the first component of that study (toxicity of bed sediments), and summarizes results from laboratory toxicity tests that compare the survival and growth of two macroinvertebrate species between bed sediments from study sites and laboratory controls. Sediment toxicity was negligible at most sites, however poor performance of one or both test species in bed sediments from several tributary sites suggests that the quality of sediments may be adversely affecting benthic macroinvertebrate communities in some tributaries to the Niagara River.

New York↗
USGS2005

Water-level altitudes in wells completed in the northern segment of the Edwards Aquifer, Travis, Williamson, and Bell Counties, Texas, March-June 2005

During March-June 2005, the U.S. Geological Survey, in cooperation with the Texas Commission on Environmental Quality (TCEQ), measured water levels in 80 Edwards aquifer wells in the outcrop of the northern segment of the aquifer in Travis, Williamson, and Bell Counties. Public-supply and private wells were selected in areas where outcrop water-level data were sparse. The altitude data can be used in the TCEQ Source Water Assessment and Protection program to help delineate zones of capture around sources of public water supply. Altitudes range from about 490 to about 935 feet above North American Vertical Datum of 1988.

Texas↗
USGS2007

Water-quality and ancillary data collected from the Arroyo Colorado near Rio Hondo, Texas, 2006

The Arroyo Colorado is in the lower Rio Grande Valley of southern Texas and extends from near Mission, Texas, eastward to the Laguna Madre estuarine and coastal marine system, which separates Padre Island from the Texas mainland. Streamflow in the Arroyo Colorado primarily is sustained by effluent from municipal wastewater-treatment plants along the stream banks. Since 1986, the tidal segment of the Arroyo Colorado from the port of Harlingen to the Laguna Madre has been designated by the State of Texas as an impaired water body because of low dissolved oxygen concentrations. Efforts to develop predictive water-quality models for the tidal segment of the Arroyo Colorado have been hampered by a lack of physical, biological, and biochemical data. Specifically, data on primary algal productivity, nutrient cycling, sediment deposition rates, and the relations between these processes and dissolved oxygen dynamics in the stream have been inadequate to support water-quality modeling efforts. The U.S. Geological Survey, in cooperation with the Texas Commission on Environmental Quality, did a study in 2006 to collect data associated with primary algal productivity, nutrient cycling, and dissolved oxygen dynamics in the tidal segment (2201) of the Arroyo Colorado near Rio Hondo. Specific objectives of the study were to (1) characterize water quality by measuring basic properties; (2) characterize the concentrations of carbon and nutrients, biochemical oxygen demand, total organic carbon, total suspended solids, and volatile suspended solids; (3) measure the seasonal differences of nutrient-dependent algal growth and algal production in the water column; (4) measure oxygen respiration or production rates; and (5) measure rates of sediment deposition.

Data Series↗
USGS2002

Real-time ground-water-level monitoring in New Jersey

A network of seven observation wells that transmit ground-water-level data on a real-time basis through satellite telemetry is operating (started May 2001) in New Jersey through a cooperative effort of the U.S. Geological Survey (USGS) and the New Jersey Department of Environmental Protection (NJDEP). The water-level data from these observation wells are transmitted every 4 hours and then are immediately posted for viewing on the Internet. This fact sheet describes the rationale for real-time monitoring of ground-water levels, the design of the network, and the equipment used to measure water levels and transmit the data to the Internet. Instructions for viewing the data are included.

New Jersey↗
USGS1995

USGS global change research

The Earth's global environment--its interrelated climate, land, oceans, fresh water, atmospheric and ecological systems-has changed continually throughout Earth history. Human activities are having ever-increasing effects on these systems. Sustaining our environment as population and demands for resources increase requires a sound understanding of the causes and cycles of natural change and the effects of human activities on the Earth's environmental systems. The U.S. Global Change Research Program was authorized by Congress in 1989 to provide the scientific understanding necessary to develop national and international policies concerning global environmental issues, particularly global climate change. The program addresses questions such as: what factors determine global climate; have humans already begun to change the global climate; will the climate of the future be very different; what will be the effects of climate change; and how much confidence do we have in our predictions? Through understanding, we can improve our capability to predict change, reduce the adverse effects of human activities, and plan strategies for adapting to natural and human-induced environmental change.

Fact Sheet↗
USGS2005

Acoustic doppler velocity monitoring within Main Spring, Barton Springs, Austin, Texas, April-September 2004-enhancing the accuracy of springflow data

Acoustic Doppler velocity (ADV) meters are sophisticated underwater monitoring instruments that use sound waves to measure water velocity in as many as three directions. In April 2004, an ADV meter was installed inside the principal orifice and discharge point of Main Spring at Barton Springs in Austin, Texas. This instrument collects velocity data that can be used to enhance the accuracy of springflow data and identify previously unrecognized hydrologic patterns. An accurate record of springflow at Barton Springs is important for several reasons. First, Barton Springs is the only known habitat for the Barton Springs salamander ( Eurycea sosorum ), a federally-listed endangered species that is dependent on reliable springflow to survive. Determination of sustainable Edwards aquifer yields compatible with the survival of the species is impossible without an accurate springflow record. Second, the 3-acre swimming pool fed by Barton Springs is enjoyed by about 340,000 people per year (2003) and is an important tourist attraction. Third, Barton Springs provides a part of Austin's municipal water supply; water from Barton Springs discharges into Town Lake on the Colorado River about 0.4 mile upstream from one of Austin's three water-supply plants. Fourth, flow in Barton Springs reflects water levels in the Barton Springs segment of the Edwards aquifer, which currently (2005) is designated a sole-source aquifer by the U.S. Environmental Protection Agency. This report, prepared by the U.S. Geological Survey, briefly summarizes the results of recent ADV-based velocity and springflow data acquisition at Barton Springs and describes an application of velocity monitoring to enhance the accuracy of springflow data.

Texas↗
USGS2014

Delivering climate science about the Nation's fish, wildlife, and ecosystems: the U.S. Geological Survey National Climate Change and Wildlife Science Center

Changes to the Earth’s climate—temperature, precipitation, and other climate variables—pose significant challenges to our Nation’s natural resources. Managers of land, water, and living resources require an understanding of the impacts of climate change—which exacerbate ongoing stresses such as habitat alteration and invasive species—in order to design effective response strategies. In 2008, Congress created the National Climate Change and Wildlife Science Center (NCCWSC) within the U.S. Geological Survey (USGS). The center was formed to address environmental challenges resulting from climate and land-use change and to provide natural resource managers with rigorous scientific information and effective tools for decision making. Located at the USGS National Headquarters in Reston, Virginia, the NCCWSC has established eight regional Department of the Interior (DOI) Climate Science Centers (CSCs) and has invested over $93 million (through fiscal year 2013) in cutting-edge climate change research.

Fact Sheet↗
USGS2025

The 3D Elevation Program—Supporting Vermont's economy

Introduction The geographic information system (GIS) community in Vermont has a long history of interdisciplinary and cooperative projects that have facilitated the leveraging of geospatial technology on myriad data acquisitions across the State. High-resolution elevation data are proving to be a resource of great economic value in dealing with many important issues in Vermont. Vermont attained statewide coverage of quality level 2 coverage of topographic light detection and ranging (lidar) data in 2019. Having access to elevation data that are exponentially more accurate than what was previously available is enabling GIS professionals to better support and empower decision makers in economically important efforts such as environmental protection, public safety, watershed management and water quality, geology, transportation planning, forest and wildlife management, local planning, and flood plain management. In addition, developing a consistent and seamless statewide topographic framework supplants the traditionally time consuming and costly approach of extensive field data collection by requiring less time and money, therefore adding economic benefits. Critical applications that meet the State’s management needs depend on lidar data that provide a highly detailed three-dimensional (3D) model of the Earth’s surface and aboveground features. The 3D Elevation Program (3DEP) is managed by the U.S. Geological Survey (USGS) in partnership with Federal, State, Tribal, U.S. territorial, and local agencies to acquire consistent lidar coverage at quality level 2 or better to meet the many needs of the Nation and Vermont. The status of available and in-progress 3DEP baseline lidar data in Vermont is shown in figure 1. 3DEP baseline lidar data include quality level 2 or better, 1-meter or better digital elevation models, and lidar point clouds, and must meet the Lidar Base Specification version 1.2 ( https://www.usgs.gov/3dep/lidarspec ) or newer requirements. The National Enhanced Elevation Assessment identified user requirements and conservatively estimated that availability of lidar data would result in at least $1.64 million in new benefits annually to the State. The top eight Vermont business uses for 3D elevation data, which are based on the estimated annual conservative benefits of 3DEP, are shown in table 2.

Vermont↗
USGS1992

Bathymetry at the head of the Cape Fear Slide, offshore North Carolina

The Cape Fear Slide is the largest mass-movement that has been observed on the U.S. Atlantic Margin. It is located off the Carolinas on the continental rise in approximately 1,200-5,500 m water depth and extends downslope for over 300 km (Popenoe, 1982). These maps show the bathymetry at the head of the Cape Fear Slide as interpreted from single-channel 3.5 kHz seismic-reflection profiles and mid-range Sea Marc I sidescan sonar imagery (Popenoe, 1985; Popenoe and others, 1991; Schmuck, 1991). The 3.5 kHz data consist of over 1000 km of profiles that were collected in 1988 for the University of North Carolina, Department of Geology. The UNC 3.5 kHz data were used as the main data set in interpreting the bathymetry. The sidescan sonar data were collected in 1980 by the U.S. Geological Survey in cooperation with the Lamont-Doherty Geological Observatory for the U.S. Bureau of Land Management Environmental Studies Program. Only 28 km (5 km swath width) of the sidescan data were used in the interpretation to identify the morphology of the main slump scarp and visible secondary scarps.

North Carolina↗
USGS2009

Development of a Watershed Boundary Dataset for Mississippi

The U.S. Geological Survey, in cooperation with the Mississippi Department of Environmental Quality, U.S. Department of Agriculture-Natural Resources Conservation Service, Mississippi Department of Transportation, U.S. Department of Agriculture-Forest Service, and the Mississippi Automated Resource Information System, developed a 1:24,000-scale Watershed Boundary Dataset for Mississippi including watershed and subwatershed boundaries, codes, names, and drainage areas. The Watershed Boundary Dataset for Mississippi provides a standard geographical framework for water-resources and selected land-resources planning. The original 8-digit subbasins (hydrologic unit codes) were further subdivided into 10-digit watersheds and 12-digit subwatersheds - the exceptions are the Lower Mississippi River Alluvial Plain (known locally as the Delta) and the Mississippi River inside levees, which were only subdivided into 10-digit watersheds. Also, large water bodies in the Mississippi Sound along the coast were not delineated as small as a typical 12-digit subwatershed. All of the data - including watershed and subwatershed boundaries, hydrologic unit codes and names, and drainage-area data - are stored in a Geographic Information System database.

Open-File Report↗
USGS2008

User's Guide to the Water-Analysis Screening Tool (WAST): A Tool for Assessing Available Water Resources in Relation to Aquatic-Resource Uses

A water-analysis screening tool (WAST) was developed by the U.S. Geological Survey, in partnership with the Pennsylvania Department of Environmental Protection, to provide an initial screening of areas in the state where potential problems may exist related to the availability of water resources to meet current and future water-use demands. The tool compares water-use information to an initial screening criteria of the 7-day, 10-year low-flow statistic (7Q10) resulting in a screening indicator for influences of net withdrawals (withdrawals minus discharges) on aquatic-resource uses. This report is intended to serve as a guide for using the screening tool. The WAST can display general basin characteristics, water-use information, and screening-indicator information for over 10,000 watersheds in the state. The tool includes 12 primary functions that allow the user to display watershed information, edit water-use and water-supply information, observe effects downstream from edited water-use information, reset edited values to baseline, load new water-use information, save and retrieve scenarios, and save output as a Microsoft Excel spreadsheet.

Open-File Report↗