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At least 793 records · Page 44Linked to original sources
USGS1946

Ground-water level fluctuations in Utah, 1936-45

Ground-water investigations in Utah by the Geological Survey of the U.S. Department of the Interior have been in progress since 1935, in cooperation with the Utah State Engineer. This cooperative work includes (1) determination of the fluctuations of water level in most of the developed ground-water areas in the state, based upon measurements which are tabulated and published annually by the Geological Survey; and (2) detailed investigations of specific ground-water areas to determine source, movement, disposal, quantity and quality of the ground water, and to show the relation of present development to the maximum economic development of which those areas are capable. Such detailed investigations have been completed during the past decade for areas in Iron, Millard, Salt Lake, Tooele, and Weber Counties, and are referred to in discussion subsequently. Similar investigations are now in progress in other areas in Davis, Iron, and Weber Counties.

Utah↗
USGS2021

Peak-flow variability, peak-flow informational needs, and consideration of regional regression analyses in managing the crest-stage gage network in Montana

The U.S. Geological Survey (USGS), in cooperation with the Montana Department of Transportation (MDT), has operated a crest-stage gage (CSG) network in Montana to collect peak-flow data since 1955. The CSG network is vital to collecting peak-flow data on small drainage basins that typically are not addressed by continuous streamflow operations. Discussions between USGS and MDT identified a need for evaluating the CSG network to allow for better decision making in the management of the network. The purpose of this report is to (1) generally describe peak-flow variability in Montana, (2) assess peak-flow informational needs relevant to MDT activities, and (3) consider the characteristics of the active CSG network in relation to addressing the informational needs. The evaluation of the CSG network is intended to assist in prioritization for discontinuation of CSGs and other activities involving changes to the CSG network. Peak-flow variability was investigated by analysis of selected peak-flow characteristics of 659 unregulated streamgages in or near Montana. A generalized peak-flow variability index ( PFVI ) was developed to provide large-scale representation of peak-flow variability in Montana. For unregulated Montana streamgages, PFVI generally monotonically decreases with increasing drainage area, although there is somewhat large (but generally consistent) variability about the locally weighted scatterplot smooth line. Presumably, highly variable small-scale hydroclimatic processes are integrated with increasing drainage area such that variability in many hydrologic characteristics is reduced. PFVI also decreases with increasing mean basin elevation and mean annual precipitation. Presumably, higher elevation and wetter hydroclimatic settings in Montana contribute to reduced variability in hydrologic characteristics. Intuitively, PFVI might be expected to generally decrease with increasing years of record because the standard deviation might typically be expected to decrease with increasing sample size. However, relations among PFVI and years of record are more complex and variable than drainage area, elevation, and precipitation. PFVI variably increases from 10 to about 40 years of record and then generally monotonically decreases from about 40 to about 105 years of record. Relations among PFVI and the years of record might be confounded by effects of drainage area because streamgages with long periods of record (greater than about 60 years) generally have large drainage areas (greater than about 100 square miles). The relations between PFVI and drainage area, mean basin elevation, mean annual precipitation, and years of record substantially differ among the eight hydrologic regions in Montana. As such, the PFVI relations were further investigated within each hydrologic region. A major use of peak-flow information by MDT is for design of road and highway infrastructure, including bridges, culverts, and roadside drainage ditches. As such, basin characteristics (including drainage area, mean basin elevation, and mean annual precipitation) of the Montana streamgage network (735 regulated and unregulated streamgages) were statistically investigated in relation to basin characteristics of 12,639 road and stream intersections in Montana. Both regulated and unregulated streamgages were investigated because the road and stream intersections are on both regulated and unregulated streams. Exploratory analyses indicated that the various relations substantially differ among the hydrologic regions. As such, the relations between the Montana streamgage network and the road and stream intersections were further investigated within each hydrologic region. An important objective of the CSG network is to provide data for developing regional regression equations (RREs) for estimating frequencies at ungaged sites in Montana. Various characteristics of the RREs substantially differ among the eight hydrologic regions in Montana. As such, the RRE characteristics were further investigated within each hydrologic region. For each of the eight hydrologic regions, various characteristics of peak-flow variability, peak-flow informational needs, and regional regression analyses were investigated in detail. Possible shortcomings of the streamgage network in each hydrologic region are identified and possible future improvements to the CSG network are presented.

Montana↗
USGS1998

Geohydrology and quality of ground water in unconsolidated aquifers near South Bend, Indiana

Introduction The water supply for the City of South Bend, Indiana, and much of surrounding St. Joseph County is provided by 36 municipal and community well fields. Some of these well fields are located near known or potential sources of ground-water contamination that could affect ground-water supplies in the near future. As population and industry grow, it will be necessary to find additional sources of water and determine their quantity and quality. Geohydrologic and water-quality data are available to identify areas for developing additional ground-water supplies, but these data have not been compiled into one source accessible to area water-resource managers. This report presents a compilation of these geohydrologic and water-quality data for the ground-water system in and near South Bend that can be used to identify potentially favorable areas for developing additional ground-water supplies for municipal use. The data were compiled by the U.S. Geological Survey, in cooperation with the South Bend Water Works, for a study area of approximately 535 square miles that includes all of St. Joseph County and the eastern part of La Porte County. A map format has been used to facilitate comparison between geohydrologic and water-quality information. Previously published geologic maps and cross sections describe the geologic setting and aquifer deposits of the study area, the hydrogeology of northeastern St. Joseph County, and the ground-water quality of northeastern St. Joseph County. Beaty (1990) and Clendenon and Beaty (1987) produced water-resource-availability reports for the St. Joseph and Kankakee River Basins.

Indiana↗
USGS2011

Generalized potentiometric surface, estimated depth to water, and estimated saturated thickness of the High Plains aquifer system, March–June 2009, Laramie County, Wyoming

The High Plains aquifer system, commonly called the High Plains aquifer in many publications, is a nationally important water resource that underlies a 111-million-acre area (173,000 square miles) in parts of eight States including Wyoming. Through irrigation of crops with groundwater from the High Plains aquifer system, the area that overlies the aquifer system has become one of the major agricultural regions in the world. In addition, the aquifer system also serves as the primary source of drinking water for most residents of the region. The High Plains aquifer system is one of the largest aquifers or aquifer systems in the world. The High Plains aquifer system underlies an area of 8,190 square miles in southeastern Wyoming. Including Laramie County, the High Plains aquifer system is present in parts of five counties in southeastern Wyoming. The High Plains aquifer system underlies 8 percent of Wyoming, and 5 percent of the aquifer system is located within the State. Based on withdrawals for irrigation, public supply, and industrial use in 2000, the High Plains aquifer system is the most utilized source of groundwater in Wyoming. With the exception of the Laramie Mountains in western Laramie County, the High Plains aquifer system is present throughout Laramie County. In Laramie County, the High Plains aquifer system is the predominant groundwater resource for agricultural (irrigation), municipal, industrial, and domestic uses. Withdrawal of groundwater for irrigation (primarily in the eastern part of the county) is the largest use of water from the High Plains aquifer system in Laramie County and southeastern Wyoming. Continued interest in groundwater levels in the High Plains aquifer system in Laramie County prompted a study by the U.S. Geological Survey in cooperation with the Wyoming State Engineer's Office to update the potentiometric-surface map of the aquifer system in Laramie County. Groundwater levels were measured in wells completed in the High Plains aquifer system from March to June 2009. The groundwater levels were used to construct a map of the potentiometric surface of the High Plains aquifer system. In addition, depth to water and estimated saturated-thickness maps of the aquifer system were constructed using the potentiometric-surface map.

Wyoming↗
USGS1979

Water-table map of Waukesha County, Wisconsin

A map (scale 1:100,000) was prepared of the water table in Waukesha County in southeastern Wisconsin using water levels from more than 1,700 wells. The work was done as part of a cooperative project between the U.S. Geological Survey, the University of Wisconsin-Extension, Geological and Natural History Survey, and the Southeastern Wisconsin Regional Planning Commission. The map shows the altitude of the water table in increments of 20 feet, with supplemental 10-foot contours. The altitude ranges from less than 670 feet at a point along the east border of the county to more than 1,000 feet above sea level at three points in the central part of the county. (Woodard-USGS)

Wisconsin↗
USGS2014

Streamflow statistics for unregulated and regulated conditions for selected locations on the Upper Yellowstone and Bighorn Rivers, Montana and Wyoming, 1928-2002

Major floods in 1996 and 1997 intensified public debate about the effects of human activities on the Yellowstone River. In 1999, the Yellowstone River Conservation District Council was formed to address conservation issues on the river. The Yellowstone River Conservation District Council partnered with the U.S. Army Corps of Engineers to carry out a cumulative effects study on the main stem of the Yellowstone River. The cumulative effects study is intended to provide a basis for future management decisions within the watershed. Streamflow statistics, such as flow-frequency data calculated for unregulated and regulated streamflow conditions, are a necessary component of the cumulative effects study. The U.S. Geological Survey, in cooperation with the Yellowstone River Conservation District Council and the U.S. Army Corps of Engineers, calculated low-flow frequency data and general monthly and annual statistics for unregulated and regulated streamflow conditions for the Upper Yellowstone and Bighorn Rivers for the 1928–2002 study period; these data are presented in this report. Unregulated streamflow represents flow conditions during the 1928–2002 study period if there had been no water-resources development in the Yellowstone River Basin. Regulated streamflow represents estimates of flow conditions during the 1928–2002 study period if the level of water-resources development existing in 2002 was in place during the entire study period.

Montana;Wyoming↗
USGS1986

Maps showing altitude of the potentiometric surface and changes in water levels in the aquifer in the Sparta and Memphis Sands in eastern Arkansas, spring 1985

Aquifers in the Tertiary Sparta and Memphis Sands are a major source of water supply for much of eastern and south-central Arkansas. Major withdrawals occur from the aquifer for industrial and public supply, with generally lesser but locally significant amounts withdrawn for agricultural uses. Water level data from wells tapping the artesian aquifer in the Sparta and Memphis Sands indicate steadily declining water levels in some areas where relatively large withdrawals occur. In addition, a simulation of water levels using projected withdrawals to the year 1990 indicated increasing water level declines in the aquifer. Because of the potential quantity and quality problems, the continual monitoring of water levels in the aquifer in the Sparta and Memphis Sands is essential for proper aquifer management and the continuation of the use of the aquifer as a major source of water for much of eastern and south-central Arkansas. The U.S. Geological Survey with the cooperation of the Arkansas Geological Commission has been monitoring water levels in the aquifer in the Sparta and Memphis Sands annually throughout the aquifer 's extent within the State of Arkansas. This report, prepared in cooperation with the Arkansas Geological Commission and the Arkansas Soil and Water Conservation Commission interprets water level data through hydrologic maps of the potentiometric surface and water level changes. The potentiometric surface map is based on water levels collected in the spring of 1985. The water level change map is based on a comparison of water levels collected in the spring of 1980 and 1985. This report includes the Sparta Sand and most of the Memphis Sand aquifer within the State of Arkansas. Little or no data are available in the northeastern part of the State where limited withdrawals from the aquifer occur. (Lantz-PTT)

Water-Resources Investigations Report↗
USGS1995

Hydrogeology of southwestern Sheboygan County, Wisconsin, in the vicinity of the Kettle Moraine Springs fish hatchery

This report describes the hydrogeology of the dolomite aquifer of Silurian age and its relation to springs in a study area in southwestern Sheboygan County, Wisconsin. The study was conducted at the Kettle Moraine Springs fish hatchery in cooperation with the Wisconsin Department of Natural Resources. The dolomite aquifer is overlain by more than 60 feet of glacial deposits. Fine-grained glacial deposits confine the dolomite aquifer in the lowland at the hatchery. Thicker, coarse-grained glacial deposits overlie the dolomite aquifer on the hills surrounding the hatchery. The coarse-grained deposits are in good hydraulic connection with the aquifer. The transmissivity and storage coefficient of the dolomite aquifer are 1,220 feet squared per day and 0.0007, respectively. Pumping from the aquifer results in drawdown in wells open to the aquifer and the effects of this pumping will decrease the greater the distance between wells. The amount of drawdown caused by pumping was estimated by means of distance-drawdown curves. Five springs and two wells open to the dolomite aquifer supply water to the hatchery. Groundwater withdrawals from fish hatchery wells affect the water level in an observation well near the springs and probably decrease the flow from the springs to the hatchery. Additional pumping from the aquifer probably will further decrease flow from the springs.

Wisconsin↗
USGS2020

Predicting barrier island habitats and oyster and seagrass habitat suitability for various restoration measures and future conditions for Dauphin Island, Alabama

Barrier islands, such as Dauphin Island, Alabama, provide numerous invaluable ecosystem services including storm damage reduction and erosion control to the mainland, habitat for fish and wildlife, carbon sequestration in marshes, water catchment and purification, recreation, and tourism. These islands are dynamic environments that are gradually shaped by currents, waves, and tides under quiescent conditions yet can evolve in the time scale of hours to days during hurricanes and other extreme storms. The ecosystems associated with these islands also face numerous other hazards, including accelerated sea-level rise, oil spills, and anthropogenic stressors. Hurricane Katrina in 2005 and the Deepwater Horizon oil spill in 2010 are two major events that have affected habitats and natural resources on Dauphin Island, Ala. The latter event prompted a cooperative effort between the U.S. Geological Survey and the U.S. Army Corps of Engineers to investigate viable, sustainable restoration measures that reduce degradation and enhance the natural resources of Dauphin Island, Ala. In collaboration with the State of Alabama and the National Fish and Wildlife Foundation, the overarching goal of the Alabama Barrier Island Restoration Feasibility Assessment project was to document baseline conditions and forecast potential conditions under varying sea-level change and storm scenarios for a no-action alternative along with a variety of restoration measures including beach and dune restoration, marsh and back-barrier restoration, and placement of sand in the littoral zone. The modeling component of this project used decadal hydrodynamic geomorphic, water quality, and habitat modeling to better understand how the various restoration measures may influence the habitat composition, sustainability, and resiliency of Dauphin Island under potential future conditions, benchmarked against the no-action case. The report covers the habitat modeling efforts associated with the Alabama Barrier Island Restoration Feasibility Assessment project. For various potential future island configurations for Dauphin Island, we predicted coverage of habitat types (for example, beach, dune, intertidal marsh, and woody vegetation) using a spatially explicit habitat model based on landscape-position information (for example, elevation and distance from shore) extracted from the hydrodynamic geomorphic outputs. Similarly, we forecasted habitat suitability for oysters and seagrass using habitat suitability index models. Another component of the Alabama Barrier Island Restoration Feasibility Assessment project, presented separately, integrates these habitat model results into a structured decision-making framework that accounts for competing objectives. Collectively, this information provides insights to natural resource managers and planners on how a restoration measure may maintain or impede natural coastal processes and provide information critical for making future-focused decisions regarding barrier island restoration.

Alabama↗
USGS2006

Ground-water hydrology and water quality of the Southern High Plains Aquifer, Cannon Air Force Base, Curry County, New Mexico, 1994-2005

In cooperation with the U.S. Air Force, the U.S. Geological Survey has collected hydrologic data about the Southern High Plains aquifer at Cannon Air Force Base in east-central New Mexico since 1994. Under the guidance of the State of New Mexico, ground-water quality of the aquifer has been analyzed as part of annual monitoring at regulated sites at the base. This report provides a summary and interpretation of all available hydrologic data collected by the U.S. Geological Survey for Cannon Air Force Base environmental managers for the regulated sites of Landfill 5 and the Sewage Lagoons between 1994 and 2005.

New Mexico↗
USGS2015

Continuous slope-area discharge records in Maricopa County, Arizona, 2004–2012

Continuous slope-area (CSA) streamgages have been developed and implemented by the U.S. Geological Survey (USGS) to enable the recording of discharge hydrographs in areas where direct discharge measurements cannot be made. The flashy nature of streamflow in parts of the arid Southwest and remote location of many sites make discharge measurements difficult or impossible to obtain. Consequently, available discharge measurements may be insufficient to develop accurate rating curves, which relate discharge to continuously recorded stage measured at standard streamgages. Nine CSA streamgages have been installed in Maricopa County, Arizona, since 2004 in cooperation with the Flood Control District of Maricopa County. This report presents the data and analysis of computed discharges from those streamgages, along with descriptions of the streamgage site and stream properties. Analyses of sources of errors and the impact stage data errors have on calculated discharge time series are considered, along with issues in data reduction. Steeper, longer stream reaches are generally less sensitive to measurement error. Other issues considered are pressure transducer drawdown, capture of flood peaks with discrete stage data, selection of stage record for development of rating curves, and minimum stages for the calculation of discharge.

Arizona↗
USGS2007

Water-quality characteristics for selected sites within the Milwaukee Metropolitan Sewerage District planning area, Wisconsin, February 2004-September 2005

The Milwaukee Metropolitan Sewerage District (MMSD) Corridor Study is a three-phase project designed to improve the understanding of water resources in the MMSD planning area to assist managers and policy makers in their decisions. Phase I of the Study involved the compilation of existing data from multiple agencies into a single database. These data were analyzed to identify spatial, temporal, and technological gaps in the planning area, and were used to develop Phase II of the Study. Phase II, the subject of this report, involved an intensive data-collection effort by the U.S. Geological Survey (USGS) in cooperation with MMSD (from February, 2004, through September, 2005). This phase addressed the data gaps identified in Phase I and completed a baseline assessment of water quality for selected stream and harbor sites in the MMSD planning area. This baseline assessment included evaluations of surface-water chemistry and microbial concentrations in the streams and harbor sites; additionally, stream sites were evaluated for discharge, sediment chemistry, fish-tissue chemistry, habitat, and the quality of biological communities (including fish, macroinvertebrates, and algae). In all, data were collected at 15 stream and 6 harbor sites within the MMSD planning area, including manual sampling and analysis for more than 220 water-quality properties and constituents at all 21 sites, stream-discharge data for 14 stream sites, and automated water-quality sampling at 4 stream sites. A bioassessment during autumn 2004 included collection of biologic-community data and stream-habitat data at wadeable streams. Quartiles of Phase II aggregate bioassessment rankings were used to divide the 14 wadeable stream sites into four groups to investigate relations between bioassessment data and site characteristic and water-quality data. Quartile numbers reflect relative water quality: quartile 1 contained sites where the bioassessment data indicated the least-degraded water quality among those sampled, and quartile 4 contained sites that indicated the most-degraded water quality. Quartiles contained the following stream sites: Quartile 1: Milwaukee River near Cedarburg, Milwaukee River at Milwaukee, Jewel Creek, and Menomonee River at Menomonee Falls; Quartile 2: Willow Creek, Root River near Franklin, and Root River at Grange Avenue; Quartile 3: Menomonee River at Wauwatosa, Oak Creek, and Little Menomonee River; and Quartile 4: Honey Creek, Underwood Creek, Lincoln Creek, and Kinnickinnic River. Site characteristics (in this case, drainage area and land use) and selected water-quality data were summarized based on the four bioassessment quartiles to determine if there were relations with the aggregate bioassessment rankings. In general, sites having the largest drainage basins with the lowest proportion of urban land use were in quartile 1, and the smallest drainage basins with the highest proportion of urban land use were in quartile 4. Major ions, indicator organisms, and wastewater compounds generally had the lowest overall results in quartile 1 and highest overall results in quartile 4, with intermediate results in quartiles 2 and 3. Results for other constituent types (nutrients, mercury, pathogenic organisms, and bed sediment) were mixed, with results for some constituents decreasing from quartile 1 to quartile 4. Where sufficient Phase I data were available, summary statistics (including medians) for chemical and biological data were calculated, allowing some comparisons to be made between Phase I and Phase II data. Comparisons between Phase I and Phase II results indicated a variety of changes with respect to water quality. Concentrations of chloride, nitrate, chlorophyll a, total phosphorus in water; arsenic in bed sediment; and fish Index of Biotic Integrity ratings generally indicated declines in water quality. However, concentrations of total nitrogen, suspended sediment, and fecal coliform in water; some trace eleme

Wisconsin↗
USGS1955

Water levels in observation wells in Santa Barbara County, California; in 1954

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.

California↗
USGS1959

Water levels in observation wells in Santa Barbara County, California, in 1958

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.

California↗
USGS1981

Hydrologic data for urban studies in the Austin, Texas, metropolitan area, 1979

Hydrologic investigations of urban watersheds in Texas were begun by theU.S. Geological Survey in 1954. Studies are now in progress in Austin, Houston, and San Antonio. Studies have been completed in the Dallas and Fort Worth areas. The Geological Survey, in cooperation with the Texas Department of Water Resources, began hydrologic studies in the Austin urban area in 1954. In cooperation with the city of Austin, the program was expanded in 1975 to include additional streamflow and rainfall gaging stations, and the collection of surface water-quality data. In 1978, the program was expanded to include a ground-water resources study of the South Austin metropolitan area in the Balcones fault zone.

Texas↗
USGS2008

Comparison of storage capacity and sedimentation trends of Lago Guayabal, Puerto Rico-December 2001 and October 2006

Lago Guayabal dam is located on the Río Jacaguas in the municipality of Villalba in southern Puerto Rico, about 4 kilometers north of the town of Juana Díaz and about 5 kilometers south of Villalba (fig. 1). The dam is owned and operated by the Puerto Rico Electric Power Authority (PREPA) and was constructed in 1913 for the irrigation of croplands in the southern coastal plains of Puerto Rico. The reservoir impounds the waters of the Río Jacaguas and those of the Río Toa Vaca, when the Toa Vaca dam overflows or releases water. The reservoir has a drainage area of 53.8 square kilometers. The dam is a concrete gravity structure with a normal pool (at top of flashboards) elevation of 103.94 meters above mean sea level (Puerto Rico Electric Power Authority, 1988). During October 2006, the U.S. Geological Survey (USGS), Caribbean Water Science Center, in cooperation with the Puerto Rico Aqueduct and Sewer Authority (PRASA) conducted a bathymetric survey of Lago Guayabal to update the reservoir storage capacity and actualize the reservoir sedimentation rate by comparing the 2006 data with the previous 2001 bathymetric survey results. The purpose of this report is to describe and document the USGS sedimentation survey conducted at Lago Guayabal during October 2006, including the methods used to update the reservoir storage capacity, sedimentation rates, and areas of substantial sediment accumulation since December 2001. The Lago Guayabal sedimentation history up to 2001 was published by the USGS in 2003 (Soler-López, 2003); therefore, this report focuses on the comparison between the 2001 and current bathymetric surveys of Lago Guayabal..

Puerto Rico↗
USGS2019

Bathymetric contour map, surface area and capacity table, and bathymetric change map for Sugar Creek Lake near Moberly, Missouri, 2018

Managers of water-supply lakes need an accurate estimate of the lake capacity to ensure that enough water is available for uses such as: providing consistent recreation pool levels, preserving downstream aquatic habitat, flood abatement, water supply, and power generation. Lake capacity is particularly important for managers of water-supply lakes during periods of drought, unexpected population growth, or exceptionally high water use in the area supplied by the lake. Sedimentation, primarily from runoff into the lake, will cause a loss of storage capacity as a lake ages; as a result, the capacity table for the lake (if one exists) will overestimate the actual capacity. Lake bathymetric changes can be demonstrated through periodic surveying, and rates of sediment accumulation can be calculated so that managers can better regulate the water supply. The U. S. Geological Survey, in cooperation with the Missouri Department of Natural Resources, completed a bathymetric survey of Sugar Creek Lake in December 2003. Sugar Creek Lake, constructed in 1922, is about 4 miles northwest of Moberly, Missouri, in Randolph County and has a surface area of about 330 acres at the spillway elevation of 746.8 feet. The lake primarily is used for recreation and drinking-water supply for the town of Moberly, Missouri. In September 2018, the U. S. Geological Survey, in cooperation with the Missouri Department of Natural Resources and the City of Moberly, Missouri, surveyed the bathymetry of Sugar Creek Lake to prepare an updated bathymetric map and a surface area and capacity table. The 2003 survey was compared with the 2018 survey to document the changes in the bathymetric surface. The comparison found that in the 14.7 years between the two surveys the lake had lost 230 acre-feet of capacity and had an average sediment accumulation of 0.96 feet.

Missouri↗
USGS1987

The U.S. Geological Survey Federal-State Cooperative Water-Resources Program, fiscal year 1986

The U.S. Geological Survey 's Federal-State Cooperative Water Resources Program has been in operation for 91 years as of fiscal year (FY) 1986. Hydrologic data collection and interpretive investigations are underway in every State, Puerto Rico, and several territories in cooperation with more than 900 State, regional and local agencies. Federal funds amounted to $49.8 million in this 50-50 matching activity. Total funding was about $106 million, which included $6.9 million furnished by cooperating agencies on an unmatched basis. The Cooperative Program comprised more than 40% of the overall FY 1986 budget of the Survey 's Water Resources Division. The areas of principal emphasis during the year included groundwater contamination, stream quality, water supply and demand, and hydrologic hazards. Information is presented on program priorities and investigations implemented under the merit proposal process. The status of water use information activities, which are being carried out in 48 states and Puerto Rico is reviewed briefly. Standard methods for collecting the data are being developed. Each state has a computerized State Water-Use Data System for storage and retrieval of water-use data for individual users or facilities. (Lantz-PTT)

Open-File Report↗