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At least 865 records · Page 48Linked to original sources
USGS2016

Hydrologic conditions in the South Coast aquifer, Puerto Rico, 2010–15

In 1958, the U.S. Geological Survey began documenting hydrologic conditions, including groundwater levels, groundwater withdrawals for agricultural irrigation and public water supply, and water quality, in the South Coast aquifer, Puerto Rico. This information has improved the understanding of the water resources of the region. The hydrologic data indicate that (1) groundwater levels declined as much as 40 feet in the Salinas area and 11 feet in the Guayama area during 2012–14; (2) groundwater withdrawals for agricultural irrigation increased from 6.0 to 10.5 million gallons per day, or 75 percent, from 2010 to 2012; and (3) total groundwater withdrawals decreased from 29.3 to 23.8 million gallons per day from 2010 to 2014. The quantity and quality of water in the aquifer is primarily affected by variations in aquifer recharge as a result of changing rainfall or modes of irrigation; however, the spatial patterns and magnitude of water withdrawals for all uses have a secondary impact on the quantity and quality of water in the aquifer. National Oceanic and Atmospheric Administration data from climatological stations indicate that the 30-year normal precipitation for the period 1991–2010 in the South Coastal and Southern Slopes climatological regions was about 37.74 and 61.61 inches, respectively; the 30-year moving average precipitation for the period 1985–2014 was 37.94 and 61.80 inches, respectively, for these regions. The mean annual precipitation during 2012–14 was 13 percent below the 30-year moving average for the South Coastal climatological region and 7.7 percent below for the Southern Slopes climatological region. When rainfall is below the 30-year moving average, recharge is diminished and groundwater levels decline. Annual precipitation in the South Coast aquifer, which includes a large part of the South Coastal and Southern Slopes climatological regions, was 39.42, 37.25, and 34.89 inches per year for 2012, 2013, and 2014, respectively. Water level declines reduce the thickness of freshwater in the unconfined parts of the South Coast aquifer. Additionally, the pumping-induced migration of poor-quality water from deep or seaward areas of the aquifer can contribute to reductions in the thickness of freshwater in the aquifer. The reduction in the freshwater saturated thickness of the aquifer in areas near Ponce, Juana Díaz, Salinas, and Guayama is of particular concern because the total saturated thickness of the aquifer is thinner in these areas. Total dissolved solids concentration in groundwater samples indicates a small positive trend in Ponce, Santa Isabel, Salinas, and Guayama. Diminished aquifer recharge during 2012 to 2015 and, to a lesser extent, increased groundwater withdrawals have resulted in a reduction in the freshwater saturated thickness of the aquifer. The reduction in freshwater saturated thickness of the aquifer may affect freshwater resources available for agriculture and public water supply. A prolonged time period with reduced aquifer recharge may have substantial implications for groundwater levels and fresh groundwater availability.

Puerto Rico↗
USGS2016

Hydrologic conditions, recharge, and baseline water quality of the surficial aquifer system at Jekyll Island, Georgia, 2012-13

An increase of groundwater withdrawals from the surficial aquifer system on Jekyll Island, Georgia, prompted an investigation of hydrologic conditions and water quality by the U.S. Geological Survey during October 2012 through December 2013. The study demonstrated the importance of rainfall as the island’s main source of recharge to maintain freshwater resources by replenishing the water table from the effects of hydrologic stresses, primarily evapotranspiration and pumping. Groundwater-flow directions, recharge, and water quality of the water-table zone on the island were investigated by installing 26 shallow wells and three pond staff gages to monitor groundwater levels and water quality in the water-table zone. Climatic data from Brunswick, Georgia, were used to calculate potential maximum recharge to the water-table zone on Jekyll Island. A weather station located on the island provided only precipitation data. Additional meteorological data from the island would enhance potential evapotranspiration estimates for recharge calculations. Groundwater levels and specific-conductance measurements showed the dependence of freshwater resources on rainfall to recharge the water-table zone of the surficial aquifer system and to influence groundwater flow on Jekyll Island. The unseasonably dry conditions during November 2012 to April 2013 induced saline water infiltration to the water-table zone from the marshland separating the Jekyll River from the island. A strong correlation (R 2 = 0.97) of specific conductance to chloride concentration in water samples from wells installed in the water-table zone provided support for the determination of seasonal directions of groundwater flow by confirming salinity changes in the water-table zone. Unseasonably wet conditions during the late spring to August caused groundwater-flow reversals in some areas. The high dependence of the water-table zone in the surficial aquifer system on precipitation to replenish the aquifer with freshwater underscored the importance of monitoring groundwater levels, water quality, and water use to identify aquifer-discharge conditions that have the potential to promote seawater encroachment and degrade freshwater resources on Jekyll Island.

Georgia↗
USGS2016

Hydropower assessment of Bolivia—A multisource satellite data and hydrologic modeling approach

This study produced a geospatial database for use in a decision support system by the Bolivian authorities to investigate further development and investment potentials in sustainable hydropower in Bolivia. The study assessed theoretical hydropower of all 1-kilometer (km) stream segments in the country using multisource satellite data and a hydrologic modeling approach. With the assessment covering the 2 million square kilometer (km 2 ) region influencing Bolivia’s drainage network, the potential hydropower figures are based on theoretical yield assuming that the systems generating the power are 100 percent efficient. There are several factors to consider when determining the real-world or technical power potential of a hydropower system, and these factors can vary depending on local conditions. Since this assessment covers a large area, it was necessary to reduce these variables to the two that can be modeled consistently throughout the region, streamflow or discharge, and elevation drop or head. First, the Shuttle Radar Topography Mission high-resolution 30-meter (m) digital elevation model was used to identify stream segments with greater than 10 km 2 of upstream drainage. We applied several preconditioning processes to the 30-m digital elevation model to reduce errors and improve the accuracy of stream delineation and head height estimation. A total of 316,500 1-km stream segments were identified and used in this study to assess the total theoretical hydropower potential of Bolivia. Precipitation observations from a total of 463 stations obtained from the Bolivian Servicio Nacional de Meteorología e Hidrología (Bolivian National Meteorology and Hydrology Service) and the Brazilian Agência Nacional de Águas (Brazilian National Water Agency) were used to validate six different gridded precipitation estimates for Bolivia obtained from various sources. Validation results indicated that gridded precipitation estimates from the Tropical Rainfall Measuring Mission (TRMM) reanalysis product (3B43) had the highest accuracies. The coarse-resolution (25-km) TRMM data were disaggregated to 5-km pixels using climatology information obtained from the Climate Hazards Group Infrared Precipitation with Stations dataset. About a 17-percent bias was observed in the disaggregated TRMM estimates, which was corrected using the station observations. The bias-corrected, disaggregated TRMM precipitation estimate was used to compute stream discharge using a regionalization approach. In regionalization approach, required homogeneous regions for Bolivia were derived from precipitation patterns and topographic characteristics using a k -means clustering approach. Using the discharge and head height estimates for each 1-km stream segment, we computed hydropower potential for 316,490 stream segments within Bolivia and that share borders with Bolivia. The total theoretical hydropower potential (TTHP) of these stream segments was found to be 212 gigawatts (GW). Out of this total, 77.4 GW was within protected areas where hydropower projects cannot be developed; hence, the remaining total theoretical hydropower in Bolivia (outside the protected areas) was estimated as 135 GW. Nearly 1,000 1-km stream segments, however, were within the boundaries of existing hydropower projects. The TTHP of these stream segments was nearly 1.4 GW, so the residual TTHP of the streams in Bolivia was estimated as 133 GW. Care should be exercised to understand and interpret the TTHP identified in this study because all the stream segments identified and assessed in this study cannot be harnessed to their full capacity; furthermore, factors such as required environmental flows, efficiency, economics, and feasibility need to be considered to better identify a more real-world hydropower potential. If environmental flow requirements of 20–40 percent are considered, the total theoretical power available reduces by 60–80 percent. In addition, a 0.72 efficiency factor further reduces the estimation by another 28 percent. This study provides the base theoretical hydropower potential for Bolivia, the next step is to identify optimal hydropower plant locations and factor in the principles to appraise a real-world power potential in Bolivia.

Open-File Report↗
USGS2017

smwrGraphs—An R package for graphing hydrologic data, version 1.1.2

This report describes an R package called smwrGraphs , which consists of a collection of graphing functions for hydrologic data within R, a programming language and software environment for statistical computing. The functions in the package have been developed by the U.S. Geological Survey to create high-quality graphs for publication or presentation of hydrologic data that meet U.S. Geological Survey graphics guidelines.

Open-File Report↗
USGS2017

Results of hydrologic monitoring on landslide-prone coastal bluffs near Mukilteo, Washington

A hydrologic monitoring network was installed to investigate landslide hazards affecting the railway corridor along the eastern shore of Puget Sound between Seattle and Everett, near Mukilteo, Washington. During the summer of 2015, the U.S. Geological Survey installed monitoring equipment at four sites equipped with instrumentation to measure rainfall and air temperature every 15 minutes. Two of the four sites are installed on contrasting coastal bluffs, one landslide scarred and one vegetated. At these two sites, in addition to rainfall and air temperature, volumetric water content, pore pressure, soil suction, soil temperature, and barometric pressure were measured every 15 minutes. The instrumentation was designed to supplement landslide-rainfall thresholds developed by the U.S. Geological Survey with a long-term goal of advancing the understanding of the relationship between landslide potential and hydrologic forcing along the coastal bluffs. Additionally, the system was designed to function as a prototype monitoring system to evaluate criteria for site selection, instrument selection, and placement of instruments. The purpose of this report is to describe the monitoring system, present the data collected since installation, and describe significant events represented within the dataset, which is published as a separate data release. The findings provide insight for building and configuring larger, modular monitoring networks.

Washington↗
USGS1971

Annual compilation and analysis of hydrologic data for Pin Oak Creek, Trinity River basin, Texas, 1969

The U.S. Soil Conservation Service is actively engaged in the installation of flood and soil erosion reducing measures in Texas under the authority of "The Flood Control Act of 1936 and 1944" and "Watershed Protection and Flood Prevention Act" (Public Law 566), as amended. The Soil Conservation Service has found a total of approximately 3,500 floodwater-retarding structures to be physically and economically feasible in Texas. As of September 30, 1969, 1,355 of these structures had been built. This watershed-development program will have varying but important effects on the natural surface- and ground-water resources of river basins, especially where a large number of the floodwater-retarding structures are built. Basic hydrologic data under natural and developed conditions are needed to appraise the effects of the structures on the yield and mode of occurrence of runoff. Hydrologic investigations of these small watersheds were begun by the U.S. Geological Survey in 1951 and are now being made in 12 areas (fig. 1). These studies are being made in cooperation with the Texas Water Development Board, the Soil Conservation Service, the San Antonio River Authority, the city of Dallas, and the Tarrant County Water Control and Improvement District No. 1. The 12 study areas were chosen to sample watersheds having different rainfall, topography, geology, and soils. In five of the study areas (North, Little Elm, Mukewater, North Elm-Little Pond, and Pin Oak Creeks), streamflow and rainfall records were collected prior to construction of the floodwater-retarding structures, thus affording the opportunity for analyses of the conditions "before and after" development. Structures have now been built in three of these study areas. A summary of the development of the floodwater-retarding structures on each study area as of September 30, 1969, is shown in table 1.

Texas↗
USGS1972

Compilation of hydrologic data, Little Elm Creek, Trinity River basin, Texas, 1968

The U.S. Soil Conservation Service is actively engaged in the installation of flood and soil erosion reducing measures in Texas under the authority of "The Flood Control Act ot 1936 and 1944" and ''Watershed Protection and Flood Prevention Act" (Public Law 566), as amended. In June 1968, the Soil Conservation Service estimated approximately 3,500 structures to be physically and economically feasible for installation in Texas. As of September 30, 1968, 1,271 of these structures had been built. This watershed-development program will have varying but important effects on the surface- and ground-water resources of river basins, especially where a large number of the floodwater-retarding structures are built. Basic hydrologic data are needed to appraise the effects of the structures on water yield and the mode of occurrence of runoff. Hydrologic investigations of these small watersheds were begun by the Geological Survey in 1951 and are now being made in 11 areas (fig. 1). These studies are being made in cooperation with t he Texas Water Development Board, the Soil Conservation Service, the San Antonio River Authority, the city of Dallas, and the Tarrant County Water Control and Improvement District No. 1. The 11 study areas were choson to sample watersheds having different rainfall, topography, geology, and soils. In four of the study areas (Mukewater, North, Little Elm, and Pin Oak Creeks), streamflow and rainfall records were collected prior to construction of the floodwater-retarding structures, thus affording the opportunity for analyses to the conditions before and after" development. Structures have now been built in three of these study areas. A summary of the development of the floodwater-retarding structures on each study area as of September 30, 1968, is shown in table 1.

Texas↗
USGS1974

Proposed hydrologic analyses of streamflow for Brazil

The objective of my assignment was to recommend what hydrologic analyses might be made using the records of stream discharge soon to be available at the gaging stations in Brazil. To attain this objective I (1) examined the streamflow records in part of the Rio Jacui basin in the state of Rio Grande do Sul for quality, length of record, and density of areal coverage; (2) locked at the available topographic maps; (3) spent one day in the field visiting gaging stations and observing general hydrologic conditions and (4) examined an isohyetal map of Brazil. The assignment was accomplished May 6-24, 1974.

Open-File Report↗
USGS1974

Summary of hydrologic conditions and effects of Walt Disney World development in the Reedy Creek Improvement District, 1966-73

The Reedy Creek Improvement District (hereinafter called the RCID) is an area of about 43 square miles (111. square kilometres) in southwest Orange and northwest Osceola Counties. Before development of Walt Disney World began (mid-1967), all of this tract of land was scrubby flatlands and swamp. Walt Disney World facilities now (1974) occupy slightly less than 10 percent of the area. Hydrologic data are available for most of the area for the 6-year period July 1967-June 1973, with some records starting before July 1967. The potentiometric surface of the Floridan aquifer near Bay Lake has declined 8 feet (2 metres) on the average. Seventy-five percent of the decline is attributed to water use in the RCID; the remaining decline is attributed to deficient rainfall since the records began in March 1966. The discharge of streams in the RCID has apparently increased. However, the hydrologic conditions were changing locally as the development of the area progressed. Because of this change, the magnitude and seasonal distribution of any eventual change in streamflow cannot be accurately appraised until additional data are obtained after the development has stabilized. Some changes in water quality have occurred, but none can be attributed to urbanization.

Florida↗
USGS1976

Geology and hydrology of radioactive solid-waste burial grounds at the Hanford Reservation, Washington

The geology and hydrology of radioactive solid waste burial grounds at the Hanford Reservation were investigated, using existing data, by the U.S. Geological Survey as part of the waste management plan of the Richland Operations Office of the Energy Research and Development Administration. The purpose of the investigation was to assist the operations office in characterizing the burial sites as to present environmental safety and as to their suitability for long-term storage (several thousand to tens of thousands of years) of radioactive sol id wastes. The burial ground sites fall into two classifications: (1) those on the low stream terraces adjacent to the Columbia River, mainly in the 100 Areas and 300 Area, and (2) those lying on the high terraces south of Gable Mountain in the 200 Areas. Evaluation of the suitability of the burial grounds for long-term storage was made almost entirely on hydrologic, geologic, and topographic criteria. Of greatest concern was the possibility that radionuclides might be leached from the buried wastes by infiltrating water and carried downward to the water table. The climate is semi-arid and the average annual precipitation is 6.4 inches at the Hanford Meteorological Station. However, the precipitation is seasonally distributed with about 50 percent occurring during the months of November, December, January, and February when evapotranspiration is negligible and conditions for infiltration are most favorable. None of the burial grounds are instrumented with monitoring devices that could be used to determine if radionuclides derived from them are reaching the water table. Burial grounds on the low stream terraces are mainly underlain by permeable materials and the water table lies at relatively shallow depths. Radionuclides conceivably could be leached from these burial grounds by percolating soil water, and radionuclides might reach the Columbia River in a relatively short time. These sites could also be inundated by erosion during a catastrophic flood. For these reasons, they are judged to be unsuited for long-term storage. Local conditions at several of these burial grounds are particularly unfavorable from the standpoint of safety. Depressions and swales at some burial grounds, such as numbers 4 and 5 in the 300 Area in which runoff can collect, enhance the possibility of water infiltrating through the buried wastes and transporting radionuclides to the water table. Also, during a high stage of the Columbia River, the water table conceivably could rise into burial grounds l and 2 of the 100 F Area. Most of the burial grounds on the low terraces contain either (1) reactor components and related equipment bearing activation products, principally cobalt-60, or (2) less hazardous radioactive materials such as uranium. The inventory of activation products in these burial grounds will decay to a safe level in a relatively short period of time (about 100 years), according to estimates made by C. D. Corbit, Douglas United Nuclear, Inc., 1969. The inventory of radionuclides is not considered by the ERDA staff to be complete, however. At these burial grounds containing activation products or less hazardous materials, investigations should be made of the radioactivity in soil and ground water beneath selected representative sites to verify that radionuclides are not migrating from the burial grounds. If migration is detected, field investigations should be made to determine the source or sources of the radionuclides and the desirability of removing the source wastes. Other burial grounds on the low terraces contain plutonium and fission products, which require long-term storage. Both the 300 WYE and the 300 North burial grounds are reported to contain plutonium in large quantities. Burial ground no. l in the 300 Area reportedly also contains plutonium. The inventory records of any other burial grounds on the low terraces suspected of containing plutonium should be reviewed to determine if pl

Open-File Report↗
USGS1976

Hydrologic changes after logging in two small Oregon coastal watersheds

Effects of clearcut, cable logging on the hydrologic characteristics of a small coastal stream in Oregon indicate an average 200 percent increase in sediment yield over a 7-year postlogging period. Annual runoff and high-flow volumes increased 19 and 1.1 inches (480 and 28 millimetres), respectively, after logging in the watershed. Clearcutting in small, spaced patches in another watershed resulted in some increase in water and sediment yields, but the increase was not statistically significant. Average monthly April-October maximum water temperatures increased significantly in the principal stream of both the clearcut and "patch-cut" watersheds. Hydrologic characteristics of both streams appear to be returning to prelogging conditions.

Oregon↗
USGS1976

Hydrology of a nuclear-processing plant site, Rocky Flats, Jefferson County, Colorado

Accidental releases of contaminants resulting from the operation of the U.S. Energy Research and Development Administration's nuclear-processing and recovery plant located on Rocky Flats will move at different rates through -different parts of the hydrologic system. Rates of movement are dependent upon the magnitude of the accidental release and the hydrologic conditions at the time of the release. For example, during wet periods, a contaminant resulting from a 5,000-gallon (19,000-1itre) release on the land surface would enter the ground-water system in about 2 to 12 hours. Ground-water flow in the Rocky Flats Alluvium might move the contaminant eastward at a rate of about 3 to 11 feet (0.9 to 3.4 metres) per day, if it remains dissolved. Maximum time to a point of discharge would be about 3 years; minimum time could be a few days. A contaminant entering a stream would then move at a rate of about 60 feet (18 metres) per minute under pool-and-riffle conditions. The rate of movement might be about 420 feet (128 metres) per minute under open-channel-flow conditions following intense thunderstorms.

Open-File Report↗
USGS1978

Hydrologic data for North Creek, Trinity River basin, Texas, 1976

The U.S. Soil Conservation Service is actively engaged in the installation of flood- and soil-erosion reducing structures in Texas under the authority of "The Flood Control Act of 1936 and 1944" and Watershed Protection and Flood Prevention Act" (Public Law 566), as amended. The Soil Conservation Service has found that approximately 3,500 floodwater-retarding structures would be physically and economically feasible in Texas. As of September 30, 1976, 1,673 (corrected figure) of these structures had been built. This watershed-development program will have varying but important effects on surface- and ground-water resources of river basins, especially where a large number of the floodwater-retarding structures are built. Basic hydrologic data under natural and developed conditions are needed to appraise the effects of the structures on the yield and mode of occurrence of runoff. During the period 1951-62, the U.S. Geological Survey began hydrologic investigations in 12 small watersheds (fig. 1). As of Sept. 30, 1976, data collection in ten of these study areas has been completed and is now in progress in the remaining two. These studies are being made in cooperation with the Texas Water Development Board, the Soil Conservation Service, the San Antonio River Authority, the city of Dallas, and the Tarrant County Control and Improvement District No. 1. The 12 study areas were chosen to sample watersheds having different rainfall, topography, geology, and soils. In five of the study areas (North, Little Elm, Mukewater, Little Pond-North Elm, and Pin Oak Creeks), streamflow and rainfall records were collected prior to construction of the floodwater-retarding structures, thus affording the opportunity for analyses of the conditions "before and after" development. A summary of the development of the floodwater-retarding structures in each study area as of Sept. 30, 1976, is shown in table 1.

Texas↗
USGS1976

Hydrologic data for urban studies in the San Antonio, Texas metropolitan area, 1976

Hydrologic investigations of urban watersheds in Texas were begun by the U.S. Geological Survey in 1954. These studies are now in progress in Austin, Dallas, Dallas County, Fort Worth, Houston, and San Antonio. The Geological Survey, in cooperation with the Texas Department of Water Resources, expanded the existing streamflow network in the San Antonio metropolitan area in May 1968 to begin urban hydrology studies in this area. In September 1968, the program was further expanded to include the collection of water-quality data.

Texas↗
USGS1978

Summary of U.S. Geological Survey investigations and hydrologic conditions in the Southwest Florida Water Management District for 1977

This report summarizes the activities of the Southwest Florida Subdistrict of the U.S. Geological Survey, Water Resources Division for fiscal year 1977. The organization and mission of the subdistrict office are described. The cooperative program for fiscal year 1977 included 41 interpretive investigations. Abstracts of twenty reports released by the subdistrict during 1977 and an extensive bibliography of reports released from 1933 to 1977 are included. The hydrologic setting of southwest Florida is outlined followed by discussions of surface-water, ground-water, and quality-of-water conditions. Hydrologic conditions in southwest Florida in 1977 are shown by the presentation of hydrographs from selected surface-water, ground-water, and lake-stage data collection sites.

Florida↗
USGS1978

Hydrologic data for water-table aquifers in the Boulder-Fort Collins-Greeley area, Front Range urban corridor, Colorado

As part of the U.S. Geological Survey 's investigations of the hydrology and geology in the Front Range Urban Corridor of Colorado, hydrologic data relating to water-table aquifers were compiled during 1976-77. These data consisting of records of 446 wells and chemical analyses of water from 208 wells in the Boulder--Fort Collins--Greeley area, are presented in tabular form. The well-data tables contain records that were collected during 1976-77. The chemical analysis tables contain records that were collected during 1956-77. State and local officials in the Boulder--Fort Collins--Greeley area may find these data useful in planning for residential, commercial, and industrial development. (Woodard-USGS)

Open-File Report↗
USGS1979

Summary of U.S. Geological Survey investigations and hydrologic conditions in the Southwest Florida Water Management District for 1978

This report summarizes water-resources investigations in the Southwest Florida Water Management District performed by the U.S. Geological Survey, Water Resources Division, for fiscal year 1978. The investigations are part of the Federal program of appraising the nation 's water resources. The cooperative program for fiscal year 1978 included 37 interpretive investigations. Abstracts of 30 reports released during 1978 and a bibliography of reports released since 1933 are included. The hydrologic setting of southwest Florida and discussions of surface-water, ground-water, and quality-of-water conditions are given. Hydrologic conditions in southwest Florida are described and illustrated by hydrographs of selected surface-water, ground-water and lake-stage data collection sites. In addition, summaries of water-use data and data on the regional observation monitor-well program are provided. (Kosco-USGS)

Florida↗
USGS1979

Summary of hydrologic data for Tampa Bypass Canal System, July 1974 to September 1976

The Tampa Bypass Canal is part of a flood-control project east of the city of Tampa under construction by the U.S. Army Corps of Engineers. It will divert floodwater from the Hillsborough River at points upstream from Tampa through a canal system to McKay Bay. The U.S. Geological Survey began a hydrologic data program in 1974 to provide data needed to identify existing hydrologic conditions and to evaluate the effects of canal construction. A network of surface-water and ground-water sites was designed to monitor changes in nutrients, trace metals, major inorganic constituents, pesticides, and benthic invertebrates along the canal system; to monitor changes in trace elements, common constituents, nitrates, specific conductance, and chlorides in the Floridan aquifer; and to monitor changes in the potentiometric surface of the Floridan aquifer. In 1974-75, the monitoring program consisted of drilling 12 monitor wells and initiation of the surface-water sampling program. In 1976, the program consisted of drilling five additional wells, continuation of the surface-water sampling, initiation of ground-water sampling program, and monitoring of discharge from springs. Water-quality data for nine surface-water sites in the basin were collected at each of the control structure sites, in the tidal portion of the canal, and at each of the major tributaries to the canal system. Fifteen ground-water sites were sampled annually to provide information on ground-water quality. Ten wells were sampled semiannually for dissolved chloride concentrations to provide information on the freshwater-saltwater interface. Ground-water levels were collected at 34 wells in the areas adjacent to the canal to monitor changes in the potentiometric surface in the Floridan aquifer. Discharge measurements from springs along the canal system were made in 1969-73 and 1976 to provide data on the quantity of ground water entering the canal. A daily discharge station was operated at structure S-160 to determine quantity of water flowing from the canal system into the bay.

Florida↗