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At least 145 records · Page 8Linked to original sources
USGS2004

A method for simulating transient ground-water recharge in deep water-table settings in central Florida by using a simple water-balance/transfer-function model

A relatively simple method is needed that provides estimates of transient ground-water recharge in deep water-table settings that can be incorporated into other hydrologic models. Deep water-table settings are areas where the water table is below the reach of plant roots and virtually all water that is not lost to surface runoff, evaporation at land surface, or evapotranspiration in the root zone eventually becomes ground-water recharge. Areas in central Florida with a deep water table generally are high recharge areas; consequently, simulation of recharge in these areas is of particular interest to water-resource managers. Yet the complexities of meteorological variations and unsaturated flow processes make it difficult to estimate short-term recharge rates, thereby confounding calibration and predictive use of transient hydrologic models. A simple water-balance/transfer-function (WBTF) model was developed for simulating transient ground-water recharge in deep water-table settings. The WBTF model represents a one-dimensional column from the top of the vegetative canopy to the water table and consists of two components: (1) a water-balance module that simulates the water storage capacity of the vegetative canopy and root zone; and (2) a transfer-function module that simulates the traveltime of water as it percolates from the bottom of the root zone to the water table. Data requirements include two time series for the period of interest?precipitation (or precipitation minus surface runoff, if surface runoff is not negligible) and evapotranspiration?and values for five parameters that represent water storage capacity or soil-drainage characteristics. A limiting assumption of the WBTF model is that the percolation of water below the root zone is a linear process. That is, percolating water is assumed to have the same traveltime characteristics, experiencing the same delay and attenuation, as it moves through the unsaturated zone. This assumption is more accurate if the moisture content, and consequently the unsaturated hydraulic conductivity, below the root zone does not vary substantially with time. Results of the WBTF model were compared to those of the U.S. Geological Survey variably saturated flow model, VS2DT, and to field-based estimates of recharge to demonstrate the applicability of the WBTF model for a range of conditions relevant to deep water-table settings in central Florida. The WBTF model reproduced independently obtained estimates of recharge reasonably well for different soil types and water-table depths.

Scientific Investigations Report↗
USGS2004

Conceptualization and simulation of the Edwards aquifer, San Antonio region, Texas

A new numerical ground-water-flow model (Edwards aquifer model) that incorporates important components of the latest information and plausible conceptualization of the Edwards aquifer was developed. The model includes both the San Antonio and Barton Springs segments of the Edwards aquifer in the San Antonio region, Texas, and was calibrated for steady-state (1939–46) and transient (1947–2000) conditions, excluding Travis County. Transient simulations were conducted using monthly recharge and pumpage (withdrawal) data. The model incorporates conduits simulated as continuously connected (other than being separated in eastern Uvalde and southwestern Medina Counties), one-cell-wide (1,320 feet) zones with very large hydraulic-conductivity values (as much as 300,000 feet per day). The locations of the conduits were based on a number of factors, including major potentiometric-surface troughs in the aquifer, the presence of sinking streams, geochemical information, and geologic structures (for example, faults and grabens). The simulated directions of flow in the Edwards aquifer model are most strongly influenced by the presence of simulated conduits and barrier faults. The simulated flow in the Edwards aquifer is influenced by the locations of the simulated conduits, which tend to facilitate flow. The simulated subregional flow directions generally are toward the nearest conduit and subsequently along the conduits from the recharge zone into the confined zone and toward the major springs. Structures simulated in the Edwards aquifer model influencing groundwater flow that tend to restrict flow are barrier faults. The influence of simulated barrier faults on flow directions is most evident in northern Medina County. A water budget is an accounting of inflow to, outflow from, and storage change in the aquifer. For the Edwards aquifer model steady-state simulation, recharge (from seepage losses from streams and infiltration of rainfall) accounts for 93.5 percent of the sources of water to the Edwards aquifer, and inflow through the northern and northwestern model boundaries contributes 6.5 percent. The largest discharges are springflow (73.7 percent) and ground-water withdrawals by wells (25.7 percent). The principal source of water to the Edwards aquifer for the Edwards aquifer model transient simulation was recharge, constituting about 60 percent of the sources of water (excluding change in storage) to the Edwards aquifer during 1956, a drought period, and about 97 percent of the sources (excluding change in storage) during 1975, a period of above-normal rainfall and recharge. The principal discharges from the Edwards aquifer for the transient simulation were springflow and withdrawals by wells. During 1956, representing drought conditions, the change in storage (net water released from storage) was much greater than recharge, accounting for 75.9 percent of the total flow compared to 14.5 percent for recharge. Conversely, during 1975, representing above-normal rainfall and recharge conditions, recharge constituted 79.9 percent of the total flow, compared to 7.1 percent for the change in storage (net water added to storage). A series of sensitivity tests was made to ascertain how the model results were affected by variations greater than and less than the calibrated values of input data. Simulated hydraulic heads in the Edwards aquifer model were most sensitive to recharge, withdrawals, hydraulic conductivity of the conduit segments, and specific yield and were comparatively insensitive to spring-orifice conductance, northern boundary inflow, and specific storage. Simulated springflow in the Edwards aquifer model was most sensitive to recharge, withdrawals, hydraulic conductivity of the conduit segments, specific yield, and increases in northern boundary inflow and was comparatively insensitive to spring-orifice conductance and specific storage.

Texas↗
USGS2005

Hydrogeology of the Mogollon Highlands, central Arizona

The Mogollon Highlands, 4,855 square miles of rugged, mountainous terrain at the southern edge of the Colorado Plateau in central Arizona, is characterized by a bedrock-dominated hydrologic system that results in an incompletely integrated regional ground-water system, flashy streamflow, and various local water-bearing zones that are sensitive to drought. Increased demand on the water resources of the area as a result of recreational activities and population growth have made necessary an increased understanding of the hydrogeology of the region. The U.S. Geological Survey conducted a study of the geology and hydrology of the region in cooperation with the Arizona Department of Water Resources under the auspices of the Arizona Rural Watershed Initiative, a program launched in 1998 to assist rural areas in dealing with water-resources issues. The study involved the analysis of geologic maps, surface-water and ground-water flow, and water and rock chemical data and spatial relationships to characterize the hydrogeologic framework. The study area includes the southwestern corner of the Colorado Plateau and the Mogollon Rim, which is the eroded edge of the plateau. A 3,000- to 4,000-foot sequence of early to late Paleozoic sedimentary rocks forms the generally south-facing scarp of the Mogollon Rim. The area adjacent to the edge of the Mogollon Rim is an erosional landscape of rolling, step-like terrain exposing Proterozoic metamorphic and granitic rocks. Farther south, the Sierra Ancha and Mazatzal Mountain ranges, which are composed of various Proterozoic rocks, flank an alluvial basin filled with late Cenozoic sediments and volcanic flows. Eight streams with perennial to intermittent to ephemeral flow drain upland regions of the Mogollon Rim and flow into the Salt River on the southern boundary or the Verde River on the western boundary. Ground-water flow paths generally are controlled by large-scale fracture systems or by karst features in carbonate rocks. Stream channels are also largely controlled by structural features, such as regional joint or fault systems. Precipitation, which shows considerable variability in amount and intensity, recharges the ground-water system along the crest of the Mogollon Rim and to a lesser extent along the crests and flanks of the rim and the Mazatzal Mountains and Sierra Ancha. Flashy runoff in the mainly bedrock stream channels is typical. Springs are distributed throughout the region, typically discharging at or above the contact of variably permeable formations along the face of the Mogollon Rim with a scattering of low-discharge springs in the Proterozoic rocks below the rim. The surface of the Colorado Plateau is the primary recharge area for the C aquifer in which ground-water flows north toward the Little Colorado River and south toward the Mogollon Highlands. Within the study area, flow from the C aquifer primarily discharges from large, stable springs in the upper East Verde River, Tonto Creek, and Canyon Creek Basins along the top of the Mogollon Rim and to the west as base flow in West Clear Creek. On the basis of chemical evidence and the distribution and flow characteristics of springs and perennial streams, the C aquifer is also the source of water for the limestone aquifer that discharges from carbonate rocks near the base of the Mogollon Rim. Vertical flow from the C aquifer, the base of which is in the Schnebly Hill Formation, recharges the limestone aquifer that discharges mainly at Fossil Springs in the western part of the study area and as base flow in Cibecue Creek on the eastern edge of the study area. Local, generally shallow aquifers of variable productivity occur in plateau and mesa-capping basalts in the sedimentary rocks of the Schnebly Hill and Supai Formations, in fractured zones of the Proterozoic Payson granite, and in the alluvium of the lower Tonto Creek Basin. Where time series data exist, such water-bearing zones are shown to be sensitive to short-

Scientific Investigations Report↗
USGS2005

Response curves for phosphorus plume lengths from reactive-solute-transport simulations of onland disposal of wastewater in noncarbonate sand and gravel aquifers

Surface-water resources in Massachusetts often are affected by eutrophication, excessive plant growth, which has resulted in impaired use for a majority of the freshwater ponds and lakes and a substantial number of river-miles in the State. Because supply of phosphorus usually is limiting to plant growth in freshwater systems, control of phosphorus input to surface waters is critical to solving the impairment problem. Wastewater is a substantial source of phosphorus for surface water, and removal of phosphorus before disposal may be necessary. Wastewater disposed onland by infiltration loses phosphorus from the dissolved phase during transport through the subsurface and may be an effective disposal method; quantification of the phosphorus loss can be simulated to determine disposal feasibility. In 2003, the U.S. Geological Survey, in cooperation with the Massachusetts Department of Environmental Protection, initiated a project to simulate distance of phosphorus transport in the subsurface for plausible conditions of onland wastewater disposal and subsurface properties. A coupled one-dimensional unsaturated-zone and three-dimensional saturated-zone reactive-solute-transport model (PHAST) was used to simulate lengths of phosphorus plumes. Knowledge of phosphorus plume length could facilitate estimates of setback distances for wastewater-infiltration sites from surface water that would be sufficient to protect the surface water from eutrophication caused by phosphorus transport through the subsurface and ultimate discharge to surface water. The reactive-solute-transport model PHAST was used to simulate ground-water flow, solute transport, equilibrium chemistry for dissolved and sorbed species, and kinetic regulation of organic carbon decomposition and phosphate mineral formation. The phosphorus plume length was defined for the simulations as the maximum extent of the contour for the 0.015 milligram-per-liter concentration of dissolved phosphorus downgradient from the infiltration bed after disposal cessation. Duration of disposal before cessation was assumed to be 50 years into an infiltration bed of 20,000 square feet at the rate of 3 gallons per square foot per day. Time for the maximum extent of the phosphorus plume to develop is on the order of 100 years after disposal cessation. Simulations indicated that phosphorus transport beyond the extent of the 0.015 milligram-per-liter concentration contour was never more than 0.18 kilogram per year, an amount that would likely not alter the ecology of most surface water. Simulations of phosphorus plume lengths were summarized in a series of response curves. Simulated plume lengths ranged from 200 feet for low phosphorus-concentration effluents (0.25 milligram per liter) and thick (50 feet) unsaturated zones to 3,400 feet for high phosphorus-concentration effluents (14 milligrams per liter) discharged directly into the aquifer (unsaturated-zone thickness of 0 feet). Plume length was nearly independent of unsaturated-zone thickness at phosphorus concentrations in the wastewater that were less than 2 milligrams per liter because little or no phosphorus mineral formed at low phosphorus concentrations. For effluents of high phosphorus concentration, plume length varied from 3,400 feet for unsaturated-zone thickness of 0 to 2,550 feet for unsaturated-zone thickness of 50 feet. Model treatments of flow and equilibrium-controlled chemistry likely were more accurate than rates of kinetically controlled reactions, notably precipitation of iron-phosphate minerals; the kinetics of such reactions are less well known and thus less well defined in the model. Sensitivity analysis indicated that many chemical and physical aquifer properties, such as hydraulic gradient and model width, did not affect the simulated plume length appreciably, but duration of discharge, size of infiltration bed, amount of dispersion, and number of sorption sites on the aquifer sediments did affect plume length appreciably. Because simulation of plume length in carbonate-mineral sediments indicated that the plume would be substantially longer than in noncarbonate-mineral sediments, the application of the response curves in locations with carbonate-mineral sediments would be inappropriate. The effect of carbonate minerals in sediments is to increase pH, which causes decreased sorption of phosphorus on aquifer sediments. Phosphorus removal from solution by precipitation onto aquifer sediments is more efficient at high concentrations of disposed phosphorus than at low concentrations. At very low phosphorus concentrations, the solubility product of phosphorus minerals is not exceeded and no phosphorus mineral forms. An important consequence is that removal of dissolved phosphorus from the plume by processes in the subsurface is decreased the more that removal efforts are applied in treatment before wastewater is disposed. Model simulations indicate that removal of phosphorus from wastewater disposed through septic systems would have the advantage of efficient phosphorus removal in the subsurface because phosphorus concentrations are high in septic-system effluent. Short plume lengths result from wastewater disposal through septic systems because of the efficient phosphorus removal and because of the low volume of wastewater involved. The simulation results for small-volume systems are not quantitative, however, because wastewater-infiltration rates are much lower than those of the higher-volume system that was used to calibrate the model and to create the plume-length response curves. The response curves for phosphorus plume lengths, as defined by the maximum extent of the 0.015 milligram-per-liter concentration contour, is clearly defined in the model simulations, although the relation between simulated plume length and protective setback distance is subject to interpretation. Phosphorus does move beyond the point at which the simulated 0.015 milligram-per-liter concentration contour has stopped, so that a determination of protective setback distance must include a consideration of whether that continued flux, or some other flux amount, is appropriate. Also, simulations indicate that phosphorus plumes do not reach their full extent until 50 to 200 years after disposal cessation, depending on concentration of phosphorus disposed. No phosphorus plume has been monitored for that long after cessation, so there is no way to verify the long-term simulation results.

Massachusetts↗
USGS2006

Water use and availability in the West Narragansett Bay area, coastal Rhode Island, 1995-99

During the 1999 drought in Rhode Island, belowaverage precipitation caused a drop in ground-water levels and streamflow was below long-term averages. The low water levels prompted the U. S. Geological Survey and the Rhode Island Water Resources Board to conduct a series of cooperative water-use studies. The purpose of these studies is to collect and analyze water-use and water-availability data in each drainage area in the State of Rhode Island. The West Narragansett Bay study area, which covers 118 square miles in part or all of 14 towns in coastal Rhode Island, is one of nine areas investigated as part of this effort. The study area includes the western part of Narragansett Bay and Conanicut Island, which is the town of Jamestown. The area was divided into six subbasins for the assessment of water-use data. In the calculation of hydrologic budget and water availability, the Hunt, Annaquatucket, and Pettaquamscutt River Basins were combined into one subbasin because they are hydraulically connected. Eleven major water suppliers served customers in the study area, and they supplied an average of 19.301 million gallons per day during 1995–99. The withdrawals from the only minor supplier, which was in the town of East Greenwich in the Hunt River Basin, averaged 0.002 million gallons per day. The remaining withdrawals were estimated as 1.186 million gallons per day from self-supplied domestic, commercial, industrial, and agricultural users. Return flows from self-disposed water (individual sewage-disposal systems) and permitted discharges accounted for 5.623 million gallons per day. Most publicly disposed water (13.711 million gallons per day) was collected by the Rhode Island Economic Development Corporation, and by the East Greenwich, Fields Point, Jamestown, Narragansett, and Scarborough wastewater-treatment facilities. This wastewater was disposed in Narragansett Bay outside of the study area. The PART program, a computerized hydrograph-separation application, was used to determine water availability in the study area on the basis of low flows measured at a nearby index station, the Pawcatuck River at Wood River Junction, Rhode Island. Water availability was defined as the 75th, 50th, and 25th percentiles of the total base flow; the base flow minus the 7-day, 10-year flow; and the base flow minus the Aquatic Base Flow at the index station. The base-flow contributions per unit area of sand and gravel deposits and of till were computed for June, July, August, and September for the index station and multiplied by the areas of sand and gravel and till in the subbasins. The calculated base flows at the index station were lowest in August at the 75th, 50th, and 25th percentiles for total base flow and for two additional low-flow scenarios. Because water withdrawals and use are greater during June, July, August, and September than at other times of the year, water availability was compared to water withdrawals in the subbasins for these summer months. Ratios were calculated by dividing the summer withdrawals by the water availability at the 75th, 50th, and 25th percentiles, and these percentiles of the base flow minus the two low flows for each subbasin. The closer this ratio is to one, the closer the withdrawals are to the estimated water available. These ratios allow comparisons of the use of water to the available water from one subbasin to another. The ratios were highest in July for the 50th percentile of the estimated gross yield minus the Aquatic Base Flow. The ratios ranged from 0.01 in the Providence and Seekonk subbasin to 0.38 in the Hunt-Annaquatucket-Pettaquamscutt subbasin for the 50th percentile of the gross yield minus the 7Q10 for August. A long-term (1941–2000) water budget was calculated for the study area to assess the basin inflows and outflows. The water withdrawals and return flows used in the budget were from 1995 through 1999. Inflow was assumed to equal outflow. The total water budget was 146.29 million gallons per day for the combined Hunt-Annaquatucket-Pettaquamscutt subbasin, 48.71 million gallons per day for the Greenwich Bay subbasin, 238.98 million gallons per day for the Providence and Seekonk Rivers subbasin, and 21.32 million gallons per day for the Conanicut Island subbasin. The estimated inflows from precipitation, streamflow from upstream basins, and wastewater return flow for the entire study area were 59.3, 38.5, and 2.2 percent, respectively. The estimated outflows for the study area from evapotranspiration, streamflow, and water withdrawals were 24.9, 73.9, and 1.2 percent, respectively.

Rhode Island↗
USGS2006

Effects of a remedial system and its operation on volatile organic compound-contaminated ground water, Operable Unit 1, Savage Municipal Well Superfund Site, Milford, New Hampshire, 1998-2004

The Savage Municipal Well Superfund site in the Town of Milford, N.H., is underlain by a 0.5-square mile plume of volatile organic compounds (VOCs), mostly tetrachloroethylene (PCE). The plume occurs mostly within a highly transmissive sand and gravel layer, but also extends into underlying till and bedrock. The plume has been divided into two areas called Operable Unit 1 (OU1), which contains the primary source area, and Operable Unit 2 (OU2), which is defined as the extended plume area. PCE concentrations in excess of 100,000 parts per billion (ppb) had been detected in the OU1 area in 1995, indicating a likely Dense Non-Aqueous Phase Liquid (DNAPL) source. In the fall of 1998, the New Hampshire Department of Environmental Services (NHDES) and the U.S. Environmental Protection Agency (USEPA) installed a remedial system in OU1 to contain and capture the dissolved VOC plume. The OU1 remedial system includes a low-permeability barrier wall that encircles the highest detected concentrations of PCE, and a series of injection and extraction wells to contain and remove contaminants. The barrier wall likely penetrates the full thickness of the sand and gravel; in most places, it also penetrates the full thickness of the underlying basal till and sits atop bedrock. Remedial injection and extraction wells have been operating since the spring of 1999 and include a series of interior (inside the barrier wall) injection and extractions wells and exterior (outside the barrier wall) injection and extraction wells. A recharge gallery outside the barrier wall receives the bulk of the treated water and reinjects it into the shallow aquifer. From 1998 to 2004, PCE concentrations decreased by an average of 80 percent at most wells outside the barrier wall. This decrease indicates (1) the barrier wall and interior extraction effectively contained high PCE concentrations inside the wall, (2) other sources of PCE did not appear to be outside of the wall, and (3) ambient ground-water flow in conjunction with the exterior remedial wells effectively remediated most of the dissolved PCE plume outside the wall. The overburden at middle depths (40 to 70 ft below land surface) downgradient from exterior extraction wells showed relatively slow decreases in PCE concentrations compared to other areas outside the barrier wall. Numerical simulation shows extraction caused the formation of a small downgradient slow-velocity zone. Because the ambient ground-water velocities are high (approximately 1 foot per day), temporary termination of extraction at the exterior wells may increase dilution downgradient from the exterior extraction wells. Extraction can also be optimized on the basis of seasonal hydrologic conditions to facilitate exterior well capture from upgradient areas outside of the barrier wall where PCE concentrations are highest. Reductions in concentrations of PCE inside the barrier wall from 1998 to 2003 were minimal near suspected source areas, indicating that the operation of interior remedial wells had not been effective in remediating dissolved PCE or the DNAPL source. Capture of the dissolved PCE plume within the barrier wall by interior extraction wells could be enhanced if operation (injection rates) increased at underutilized interior injection wells, thereby increasing hydraulic gradients.

Scientific Investigations Report↗
USGS2007

Estimated water use and availability in the Pawtuxet and Quinebaug River basins, Rhode Island, 1995-99

Water availability became a concern in Rhode Island during a drought in 1999, and an investigation was needed to assess demands on the hydrologic system from withdrawals during periods of little to no precipitation. The low water levels during the drought prompted the U.S. Geological Survey and the Rhode Island Water Resources Board to begin a series of studies on water use and availability in each drainage area in Rhode Island for 1995–99. The study area for this report, which includes the Pawtuxet River Basin in central Rhode Island (231.6 square miles) and the Quinebaug River Basin in western Rhode Island (60.97 square miles), was delineated as the surface-water drainage areas of these basins. During the study period from 1995 through 1999, two major water suppliers withdrew an average of 71.86 million gallons per day (Mgal/d) from the Pawtuxet River Basin; of this amount, about 35.98 Mgal/d of potable water were exported to other basins in Rhode Island. The estimated water withdrawals from minor water suppliers were 0.026 Mgal/d in the Pawtuxet River Basin and 0.003 Mgal/d in the Quinebaug River Basin. Total self-supply withdrawals were 2.173 Mgal/d in the Pawtuxet River Basin and 0.360 Mgal/d in the Quinebaug River Basin, which has no public water supply. Total water use averaged 18.07 Mgal/d in the Pawtuxet River Basin and 0.363 Mgal/d in the Quinebaug River Basin. Total return flow in the Pawtuxet River Basin was 30.64 Mgal/d, which included about 12.28 Mgal/d that were imported from other basins in Rhode Island. Total return flow was 0.283 Mgal/d in the Quinebaug River Basin. During times of little to no recharge in the form of precipitation, the surface- and ground-water flows are from storage primarily in the stratified sand and gravel deposits; water also flows through the till deposits, but at a slower rate. The ground water discharging to the streams during times of little to no recharge from precipitation is referred to as base flow. The PART program, a computerized hydrograph-separation application, was used to analyze the data collected at two selected index stream-gaging stations to determine water availability on the basis of the 75th, 50th, and 25th percentiles of the total base flow; the base flow for the 7-day, 10-year low-flow scenario; and the base flow for the Aquatic Base Flow scenario for both stations. The index stream-gaging stations used in the analysis were the Branch River at Forestdale, Rhode Island (period of record 1957–1999) and the Nooseneck River at Nooseneck, Rhode Island (period of record 1964–1980). A regression equation was used to estimate unknown base-flow contributions from sand and gravel deposits at the two stations. The base-flow contributions from sand and gravel deposits and till deposits at the index stations were computed for June, July, August, and September within the periods of record, and divided by the area of each type of surficial deposit at each index station. These months were selected because they define a period when there is usually an increased demand for water and little to no precipitation. The base flows at the stream-gaging station Branch River at Forestdale, Rhode Island were lowest in August at the 75th, 50th, and 25th percentiles (29.67, 21.48, and 13.30 Mgal/d, respectively). The base flows at the stream-gaging station Nooseneck River at Nooseneck, Rhode Island were lowest in September at the 75th percentile (3.551 Mgal/d) and lowest in August at the 50th and 25th percentiles (2.554 and 1.811 Mgal/d). The base flows per unit area for the index stations were multiplied by the areas of sand and gravel and till in the studyarea subbasins to determine the amount of available water for each scenario. The water availability in the Pawtuxet River Basin at the 50th percentile ranged from 126.5 Mgal/d in August to 204.7 Mgal/d in June, and the total gross water availability for the 7-day, 10-year low-flow scenario at the 50th percentile ranged from 112.2 Mgal/d in August to 190.4 Mgal/d in June. The Scituate Reservoir safe yield was 83 Mgal/d in all scenarios. Water availability in the Quinebaug River Basin ranged from 13.94 Mgal/d in August to 30.53 Mgal/d in June at the 50th percentile. The total gross water availability for the 7-day, 10-year low-flow scenario at the 50th percentile ranged from 14.26 Mgal/d in August to 42.69 Mgal/d in June. Because water withdrawals and use are greater during the summer than other times of the year, water availability in June, July, August, and September was compared to water withdrawals in the basin and subbasins. The ratios of water withdrawn to water available were calculated for the 75th, 50th, and 25th percentiles for the subbasins; the closer the ratio is to 1, the closer the withdrawals are to the estimated water available, and the less net water is available. Withdrawals in July were higher than in the other summer months in both basins. In the Pawtuxet River Basin, the ratios were close to 1 in July for the estimated gross yield (from sand and gravel and from till and from the Scituate Reservoir safe yield), 7-day, 10-year low-flow scenario, and Aquatic Base Flow scenario at the 75th percentile and in August for all three scenarios at the 50th and 25th percentiles. In the Quinebaug River Basin, the ratios were close to 1 in August for the estimated gross yield; 7-day, 10-year low-flow scenario; and Aquatic Base Flow scenario. A long-term water budget was calculated for 1941 through 1999 to identify and assess the basin and subbasin inflow and outflows for the Pawtuxet and Quinebaug River Basins. The water withdrawals and return flows used in the budget were from 1995 through 1999. Inflow was assumed to be equal to outflow; total inflows and outflows were 574.9 Mgal/d in the Pawtuxet River Basin and 148.4 Mgal/d in the Quinebaug River Basin. Precipitation and return flow were 95 and 5 percent of the estimated inflows to the Pawtuxet River Basin, respectively. Precipitation was 100 percent of the estimated inflow to the Quinebaug River Basin; return flow was less than 1 percent of the inflow. Evapotranspiration, streamflow, and water withdrawals were 46, 41, and 13 percent, respectively, of the estimated outflows in the Pawtuxet River Basin. Evapotranspiration and streamflow were 49 and 51 percent, respectively, of the estimated outflows in the Quinebaug River Basin. Water withdrawals were less than 1 percent of outflows in the Quinebaug River Basin.

Rhode Island↗
USGS2006

Simulation of Streamflow and Water Quality to Determine Fecal Coliform and Nitrate Concentrations and Loads in the Mad River Basin, Ohio

The Hydrological Simulation Program Fortran (HSPF) was used to simulate the concentrations and loads of fecal coliform and nitrate for streams in the Mad River Basin in west-central Ohio during the period 1999 through 2003. The Mad River Basin was divided into subbasins that were defined either by the 14-digit Hydrologic Unit (HU) boundaries or by streamflow-gaging-station locations used in the model. Model calibration and simulation processes required the formation of nine meteorologic zones to input meteorologic time-series data and water-quality data. Sources of fecal coliform and nitrate from wastewater-treatment discharges and combined sewer overflow discharges (CSOs) within the City of Springfield were point sources simulated in the model. Failing septic systems and cattle with direct access to streams were nonpoint sources included in the study but treated in the model as point sources. Other nonpoint sources were addressed by adjusting interflow and ground-water concentrations in the subsurface and maximum storage capacities and accumulation rates of the simulated constituents on the land surface for each meteorologic zone. Simulation results from the calibrated model show that several HUs exceeded the water-quality standard of 1,000 colony-forming units per 100 mL for fecal coliform based on the maximum 30-day geometric mean. Most HUs with high fecal coliform counts were within or downstream from the City of Springfield. No water-quality standard has been set for instream nitrate concentrations; however, the Ohio Environmental Protection Agency (Ohio EPA) considered a concentration of 5 mg/L or greater to be of concern. Simulation results indicate that several HUs in the agricultural areas of the basin exceeded this level. The calibrated model was modified to create scenarios that simulated loads of fecal coliform and nitrate that were either reduced or eliminated from selected sources. The revised models included the elimination of failing septic systems, elimination of direct access of cattle to streams, decrease in fecal coliform loads from the CSOs and selected wastewater-treatment facilities, and decrease in nitrate loads from land surfaces. The fecal coliform source-reduction model decreased the fecal coliform concentrations below a target concentration of 1,000 colonies per 100 milliliters for all HU outlets and decreased the load at the mouth of the Mad River by 73 percent. The nitrate source-reduction model decreased some HU mean concentrations to 5 milligrams per liter or less and decreased the load at the mouth of the Mad River by 52 percent. Other reduction scenarios may be run by Ohio EPA with the intent of identifying a management strategy that will attain a target concentration for the Mad River Basin.

Scientific Investigations Report↗
USGS2006

Development of a Precipitation-Runoff Model to Simulate Unregulated Streamflow in the Salmon Creek Basin, Okanogan County, Washington

Surface water has been diverted from the Salmon Creek Basin for irrigation purposes since the early 1900s, when the Bureau of Reclamation built the Okanogan Project. Spring snowmelt runoff is stored in two reservoirs, Conconully Reservoir and Salmon Lake Reservoir, and gradually released during the growing season. As a result of the out-of-basin streamflow diversions, the lower 4.3 miles of Salmon Creek typically has been a dry creek bed for almost 100 years, except during the spring snowmelt season during years of high runoff. To continue meeting the water needs of irrigators but also leave water in lower Salmon Creek for fish passage and to help restore the natural ecosystem, changes are being considered in how the Okanogan Project is operated. This report documents development of a precipitation-runoff model for the Salmon Creek Basin that can be used to simulate daily unregulated streamflows. The precipitation-runoff model is a component of a Decision Support System (DSS) that includes a water-operations model the Bureau of Reclamation plans to develop to study the water resources of the Salmon Creek Basin. The DSS will be similar to the DSS that the Bureau of Reclamation and the U.S. Geological Survey developed previously for the Yakima River Basin in central southern Washington. The precipitation-runoff model was calibrated for water years 1950-89 and tested for water years 1990-96. The model was used to simulate daily streamflows that were aggregated on a monthly basis and calibrated against historical monthly streamflows for Salmon Creek at Conconully Dam. Additional calibration data were provided by the snowpack water-equivalent record for a SNOTEL station in the basin. Model input time series of daily precipitation and minimum and maximum air temperatures were based on data from climate stations in the study area. Historical records of unregulated streamflow for Salmon Creek at Conconully Dam do not exist for water years 1950-96. Instead, estimates of historical monthly mean unregulated streamflow based on reservoir outflows and storage changes were used as a surrogate for the missing data and to calibrate and test the model. The estimated unregulated streamflows were corrected for evaporative losses from Conconully Reservoir (about 1 ft3/s) and ground-water losses from the basin (about 2 ft3/s). The total of the corrections was about 9 percent of the mean uncorrected streamflow of 32.2 ft3/s (23,300 acre-ft/yr) for water years 1949-96. For the calibration period, the basinwide mean annual evapotranspiration was simulated to be 19.1 inches, or about 83 percent of the mean annual precipitation of 23.1 inches. Model calibration and testing indicated that the daily streamflows simulated using the precipitation-runoff model should be used only to analyze historical and forecasted annual mean and April-July mean streamflows for Salmon Creek at Conconully Dam. Because of the paucity of model input data and uncertainty in the estimated unregulated streamflows, the model is not adequately calibrated and tested to estimate monthly mean streamflows for individual months, such as during low-flow periods, or for shorter periods such as during peak flows. No data were available to test the accuracy of simulated streamflows for lower Salmon Creek. As a result, simulated streamflows for lower Salmon Creek should be used with caution. For the calibration period (water years 1950-89), both the simulated mean annual streamflow and the simulated mean April-July streamflow compared well with the estimated uncorrected unregulated streamflow (UUS) and corrected unregulated streamflow (CUS). The simulated mean annual streamflow exceeded UUS by 5.9 percent and was less than CUS by 2.7 percent. Similarly, the simulated mean April-July streamflow exceeded UUS by 1.8 percent and was less than CUS by 3.1 percent. However, streamflow was significantly undersimulated during the low-flow, baseflow-dominated months of November through F

Scientific Investigations Report↗
USGS2007

Recharge area, base-flow and quick-flow discharge rates and ages, and general water quality of Big Spring in Carter County, Missouri, 2000-04

Exploration for lead deposits has occurred in a mature karst area of southeast Missouri that is highly valued for its scenic beauty and recreational opportunities. The area contains the two largest springs in Missouri (Big Spring and Greer Spring), both of which flow into federally designated scenic rivers. Concerns about potential mining effects on the area ground water and aquatic biota prompted an investigation of Big Spring. Water-level measurements made during 2000 helped define the recharge area of Big Spring, Greer Spring, Mammoth Spring, and Boze Mill Spring. The data infer two distinct potentiometric surfaces. The shallow potentiometric surface, where the depth-to-water is less than about 250 feet, tends to mimic topographic features and is strongly controlled by streams. The deep potentiometric surface, where the depth-to-water is greater than about 250 feet represents ground-water hydraulic heads within the more mature karst areas. A highly permeable zone extends about 20 mile west of Big Spring toward the upper Hurricane Creek Basin. Deeper flowing water in the Big Spring recharge area is directed toward this permeable zone. The estimated sizes of the spring recharge areas are 426 square miles for Big Spring, 352 square miles for Greer Spring, 290 square miles for Mammoth Spring, and 54 square miles for Boze Mill Spring. A discharge accumulation curve using Big Spring daily mean discharge data shows no substantial change in the discharge pattern of Big Spring during the period of record (water years 1922 through 2004). The extended periods when the spring flow deviated from the trend line can be attributed to prolonged departures from normal precipitation. The maximum possible instantaneous flow from Big Spring has not been adequately defined because of backwater effects from the Current River during high-flow conditions. Physical constraints within the spring conduit system may restrict its maximum flow. The largest discharge measured at Big Spring during the period of record (water years 1922 through 2004) was 1,170 cubic feet per second on December 7, 1982. The daily mean water temperature of Big Spring was monitored during water years 2001 through 2004 and showed little variability, ranging from 13 to 15° C (degree Celsius). Water temperatures generally vary less than 1° C throughout the year. The warmest temperatures occur during October and November and decrease until April, indicating Big Spring water temperature does show a slight seasonal variation. The use of the traditional hydrograph separation program HYSEP to determine the base flow and quick flow or runoff components at Big Spring failed to yield base-flow and quick-flow discharge curves that matched observations of spring characteristics. Big Spring discharge data were used in combination with specific conductance data to develop an improved hydrograph separation method for the spring. The estimated annual mean quick flow ranged from 15 to 48 cubic feet per second for the HYSEP analysis and ranged from 26 to 154 cubic feet per second for the discharge and specific conductance method for water years 2001 to 2004. Using the discharge and specific conductance method, the estimated base-flow component rises abruptly as the spring hydrograph rises, attains a peak value on the same day as the discharge peak, and then declines abruptly from its peak value. Several days later, base flow begins to increase again at an approximately linear trend, coinciding with the time at which the percentage of quick flow has reached a maximum after each recharge-induced discharge peak. The interval between the discharge peak and the peak in percentage quick flow ranges from 8 to 11 days for seven hydrograph peaks, consistent with quick-flow traveltime estimates by dye-trace tests from the mature karst Hurricane Creek Basin in the central part of the recharge area. Concentrations of environmental tracers chlorofluorocarbons (CFCs: CFC-11, CFC-12, CFC-113), and sulfur hexafluoride in discharge from Big Spring vary approximately linearly with percent quick flow from about 5 to 45 percent of discharge. Linear extrapolation to 100 percent quick flow implies CFC and SF 6 concentrations nearly identical to those in the 2002 atmosphere and indicates a modern age for the quick-flow component. Tracer concentrations for less than about 5 percent quick flow are increasingly lower than those expected from linear extrapolation to zero percent quick flow, indicating that the reservoir of older water in the Big Spring watershed may be a series of water mixtures with piston-flow ages greater than those obtained by extrapolation to zero percent quick flow. Each sample point with a low percentage of quick flow (less than 5 percent) may be a unique mixture. Environmental tracer data from Big Spring plot intermediate to the simple binary mixing of modern and old, pre-tracer water and results from the exponential mixture model. The mean ages of waters in the base-flow component approximately range from 30 to 200 years. The mean age of the base-flow component is youngest (30 to 40 years) in samples containing the highest quick-flow component (45 percent quick flow) and increases to 200 years or more as the fraction of quick flow decreases to less than 5 percent. Tritium data are consistent with a model of dilution of a modern component with an old, pre-tracer component and indicates that the old fraction is mostly pre-1960s in age with mean residence time of more than several hundred years. All of the samples from Big Spring and Greer Spring have water temperatures warmer than their nitrogen-argon recharge temperature, which range from approximately 10.5 to 14° C, suggesting recharge to the Big Spring watershed occurs primarily in late winter to early spring. The water temperatures at Big Spring are consistent with relatively shallow circulation (less than about 600 feet), and the water does not appear to be warmed by deep circulation along a geothermal gradient. Specific conductance values and concentrations of most inorganic constituents in water samples from Big Spring generally decrease with increasing discharge because of dilution with quick-flow water of lower ionic strength. Concentrations of some constituents such as chloride and nitrite plus nitrate, and fecal coliform densities, however, did not decrease with increasing discharge, indicating that quick flow probably is a more important source of these constituents compared to base flow. Water samples from Big Spring plot along the line of dolomite dissolution by carbonic acid, are at equilibrium with dolomite and calcite, and have a molar ratio of Ca:Mg of near 1, indicating dissolution of the mineral dolomite as the primary control on concentrations of calcium, magnesium, and bicarbonate. The flux of calcium and magnesium from Big Spring represents the dissolution of about 1,950 cubic feet of dolomite per day. The suspended sediment load of Big Spring was estimated to range from about 1 to about 70 tons per day, and the sediment load during base-flow periods ranged from about 1 to about 7 tons per day.

Missouri↗
USGS2008

Simulation of the Quantity, Variability, and Timing of Streamflow in the Dennys River Basin, Maine, by Use of a Precipitation-Runoff Watershed Model

The U.S. Geological Survey (USGS), in cooperation with the Maine Department of Marine Resources Bureau of Sea Run Fisheries and Habitat, began a study in 2004 to characterize the quantity, variability, and timing of streamflow in the Dennys River. The study included a synoptic summary of historical streamflow data at a long-term streamflow gage, collecting data from an additional four short-term streamflow gages, and the development and evaluation of a distributed-parameter watershed model for the Dennys River Basin. The watershed model used in this investigation was the USGS Precipitation-Runoff Modeling System (PRMS). The Geographic Information System (GIS) Weasel was used to delineate the Dennys River Basin and subbasins and derive parameters for their physical geographic features. Calibration of the models used in this investigation involved a four-step procedure in which model output was evaluated against four calibration data sets using computed objective functions for solar radiation, potential evapotranspiration, annual and seasonal water budgets, and daily streamflows. The calibration procedure involved thousands of model runs and was carried out using the USGS software application Luca (Let us calibrate). Luca uses the Shuffled Complex Evolution (SCE) global search algorithm to calibrate the model parameters. The SCE method reliably produces satisfactory solutions for large, complex optimization problems. The primary calibration effort went into the Dennys main stem watershed model. Calibrated parameter values obtained for the Dennys main stem model were transferred to the Cathance Stream model, and a similar four-step SCE calibration procedure was performed; this effort was undertaken to determine the potential to transfer modeling information to a nearby basin in the same region. The calibrated Dennys main stem watershed model performed with Nash-Sutcliffe efficiency (NSE) statistic values for the calibration period and evaluation period of 0.79 and 0.76, respectively. The Cathance Stream model had an NSE value of 0.68. The Dennys River Basin models make use of limited streamflow-gaging station data and provide information to characterize subbasin hydrology. The calibrated PRMS watershed models of the Dennys River Basin provide simulated daily streamflow time series from October 1, 1985, through September 30, 2006, for nearly any location within the basin. These models enable natural-resources managers to characterize the timing and quantity of water moving through the basin to support many endeavors including geochemical calculations, water-use assessment, Atlantic salmon population dynamics and migration modeling, habitat modeling and assessment, and other resource-management scenario evaluations. Characterizing streamflow contributions from subbasins in the basin and the relative amounts of surface- and ground-water contributions to streamflow throughout the basin will lead to a better understanding of water quantity and quality in the basin. Improved water-resources information will support Atlantic salmon protection efforts.

Scientific Investigations Report↗
USGS2009

Watershed Models for Decision Support for Inflows to Potholes Reservoir, Washington

A set of watershed models for four basins (Crab Creek, Rocky Ford Creek, Rocky Coulee, and Lind Coulee), draining into Potholes Reservoir in east-central Washington, was developed as part of a decision support system to aid the U.S. Department of the Interior, Bureau of Reclamation, in managing water resources in east-central Washington State. The project is part of the U.S. Geological Survey and Bureau of Reclamation collaborative Watershed and River Systems Management Program. A conceptual model of hydrology is outlined for the study area that highlights the significant processes that are important to accurately simulate discharge under a wide range of conditions. The conceptual model identified the following factors as significant for accurate discharge simulations: (1) influence of frozen ground on peak discharge, (2) evaporation and ground-water flow as major pathways in the system, (3) channel losses, and (4) influence of irrigation practices on reducing or increasing discharge. The Modular Modeling System was used to create a watershed model for the four study basins by combining standard Precipitation Runoff Modeling System modules with modified modules from a previous study and newly modified modules. The model proved unreliable in simulating peak-flow discharge because the index used to track frozen ground conditions was not reliable. Mean monthly and mean annual discharges were more reliable when simulated. Data from seven USGS streamflow-gaging stations were used to compare with simulated discharge for model calibration and evaluation. Mean annual differences between simulated and observed discharge varied from 1.2 to 13.8 percent for all stations used in the comparisons except one station on a regional ground-water discharge stream. Two thirds of the mean monthly percent differences between the simulated mean and the observed mean discharge for these six stations were between -20 and 240 percent, or in absolute terms, between -0.8 and 11 cubic feet per second. A graphical user interface was developed for the user to easily run the model, make runoff forecasts, and evaluate the results. The models; however, are not reliable for managing short-term operations because of their demonstrated inability to match individual storm peaks and individual monthly discharge values. Short-term forecasting may be improved with real-time monitoring of the extent of frozen ground and the snow-water equivalent in the basin. Despite the models unreliability for short-term runoff forecasts, they are useful in providing long-term, time-series discharge data where no observed data exist.

Scientific Investigations Report↗
USGS2011

Hydrogeology and simulation of groundwater flow in fractured rock in the Newark basin, Rockland County, New York

Groundwater in the Newark basin aquifer flows primarily through discrete water-bearing zones parallel to the strike and dip of bedding, whereas flow perpendicular to the strike is restricted, thereby imparting anisotropy to the groundwater flow field. The finite-element model SUTRA was used to represent bedrock structure in the aquifer by spatially varying the orientation of the hydraulic conductivity tensor to reflect variations in the strike and dip of the bedding. Directions of maximum and medium hydraulic conductivity were oriented parallel to the bedding, and the direction of minimum hydraulic conductivity was oriented perpendicular to the bedding. Groundwater flow models were prepared to simulate local flow in the vicinity of the Spring Valley well field and regional flow through the Newark basin aquifer. The Newark basin contains sedimentary rocks deposited as alluvium during the Late Triassic and is one of a series of basins that developed when Mesozoic rifting of the super continent Pangea created the Atlantic Ocean. The westward-dipping basin is filled with interbedded facies of coarse-grained to fine-grained rocks that were intruded by diabase associated with Jurassic volcanism. The Newark basin aquifer is bounded to the north and east by the Palisades sill and to the west by the Ramapo Fault. Although the general dip of bedding is toward the fault, mapping of conglomerate beds indicates the rocks are folded into broad anticlines and synclines. An alternative, more uniform pattern of regional structure, based on interpolated strike and dip measurements from a number of sources, has also been proposed. Two groundwater flow models (A for the former type of bedrock structure and B for the latter type) were developed to represent these alternative depictions of bedrock structure. Transient simulations were calibrated to reproduce measured water-level recoveries in a 9.3 mi&sup2 area surrounding the Spring Valley well field during a 5-day aquifer test in 1992. The models represented a 330-ft thick rock mass divided vertically into 10 equally spaced layers and were calibrated through nonlinear regression. Results of model B best matched the observed water-level recoveries with an estimated hydraulic conductivity of 9.5 ft/day, specific storage of 7.6 x 10 -6 ft -1, and K max : K min anisotropy ratio (hydraulic conductivity parallel to bedding: perpendicular to bedding) of 72:1. Model error was 50 percent greater in model A because the assumed structure did not match the actual strike of bedding in this area. Steady-state simulations of regional flow through the 85.4-mi2 modeled extent of the Newark basin aquifer represented both the alluvial aquifer beneath the Mawah River and the fractured bedrock. The rock mass was divided into two aquifer units: an upper 500-ft thick unit divided into 10 equally spaced layers through which most groundwater is assumed to flow and a lower unit divided into 7 layers with increasing thickness. Models were calibrated through nonlinear regression to average water levels measured in 140 wells from August 2005 through April 2007. Water levels simulated using the two models were similar and generally matched those observed, and the average recharge rate estimated using both models was 19 inches/year for the simulated period. Estimated transmissivity parallel to the strike of bedding (1,100 ft&sup2/d) was uniform in two transmissivity (T) zones in model A, but in model B the transmissivity of a high T zone (1,600 ft&sup2/d), delineated on the basis of aquifer test data, was slightly greater than in a low T zone (1,300 ft&sup2/d). The K max : K min anisotropy was estimated to be 58:1 in model A and 410:1 in model B, so the proportion of flow perpendicular to bedding is less in model B than in model A. Distributions of groundwater age simulated with models A and B are similar and indicate that most shallow ground-water (225 ft below the bedrock surface) is 5 t

Scientific Investigations Report↗
USGS2018

Groundwater chemistry and water-level elevations in bedrock aquifers of the Piceance and Yellow Creek watersheds, Rio Blanco County, Colorado, 2013–16

The Piceance and Yellow Creek watersheds in Rio Blanco County, Colorado, are known to contain important energy resources (oil shale and natural gas) and mineral resources (nahcolite). The primary sources of fresh groundwater in the Piceance and Yellow Creek watersheds are bedrock aquifers in the Uinta and Green River Formations. The aquifers are divided into an upper and lower aquifer separated by a regionally extensive semiconfining layer. These aquifers provide water to streams and springs in the watersheds and are an important resource to people living and working in the area. Development of energy and mineral resources has the potential to affect the quality of groundwater in several ways. The Bureau of Land Management and the U.S. Geological Survey began groundwater monitoring in 2010 to characterize the groundwater quality and water-level elevations of shallow bedrock aquifers in the Piceance and Yellow Creek watersheds. The purpose of this report is to present ground-water chemistry and water-level elevations collected during 2013–16. Comparisons are made to data that were collected from the bedrock aquifers from 2010 to 2012 to identify the potential for changes in water quality and water-level elevations. Appreciable changes in water-level elevations and hydraulic gradient were observed in early April 2015 in two wells completed in the upper and lower aquifers. The hydraulic gradient between the two wells was consistently downward from the upper aquifer to the lower aquifer during 2010–15; however, in early April 2015, the gradient changed from downward to upward between the two aquifers. Overall, water-level elevations declined by about 14 and 11 feet in the upper and lower aquifers, respectively, from 2013 to 2016. Previously published data estimated groundwater ages at 1,200 years old in the upper aquifer and 9,600 years old in the lower aquifer. These groundwater ages indicate that ground-water was recharged over thousands of years. With such long periods of time for aquifer recharge, declines in water-level elevation over short time steps (a few months) have important implications for sustainable management of this resource. Solution mining activities or drilling for oil and natural gas in the area could be related to the changes observed in water-level elevations in these wells; however, further investigation would be needed to evaluate causation. Changes in major-ion chemistry were evaluated in the bedrock aquifer using time series plots of select major-ion data from 2010 to 2016. Major-ion chemistry was variable for a single well from 2010 to 2016 where alkalinity and sulfate were the most variable constituents. One possible explanation for the observed changes in major-ion chemistry may be that the sample depth for that well no longer represents the most appreciable flow in the borehole. On a larger scale, potential changes in flow within the borehole may indicate changes in the regional flow system. Methane and volatile organic compound concentrations were evaluated using a similar approach to that of major ions and had similar findings. Methane concentrations in wells sampled from 2010 to 2016 were generally constant. The only exception was observed at a single well where the range of methane concentrations was from 57.4 (2010) to 4.02 milligrams per liter (2013). This is the same well where changes in water-level elevation, hydraulic gradient, and major-ion chemistry were observed, providing multiple lines of evidence to indicate change in the bedrock aquifers. Sampling of a well located in an area with little energy development but where faults or fractures could provide a path for the migration of fluids indicate mixing of groundwater between the upper and lower aquifers.

Colorado↗
USGS2004

Water resources data, Florida, water year 2004, volume 4: northeast Florida

This report series for the 2004 water year for the state of Florida consists of records for continuous or daily discharge for 405 streams, periodic discharge for 12 streams, continuous or daily stage for 159 streams, periodic stage for 19 streams, peak stage and discharge for 30 streams, continuous or daily elevations for 14 lakes, periodic elevations for 23 lakes, continuous ground-water levels for 408 wells, periodic ground-water levels for 1,188 wells, and quality-of-water for 140 surface-water sites and 240 wells. This volume (Volume 4, Northwest Florida) contains records of continuous or daily discharge for 75 streams, periodic discharge for 2 streams, continuous or daily stage for 11 streams, periodic stage for 2 streams, peak stage and discharge for 22 streams, continuous or daily elevations for 1 lake, periodic elevations for 0 lakes, continuous ground-water levels for 3 wells, periodic ground-water levels for 0 wells, and quality-of-water for 3 surface-water sites and 0 wells. These data represent the National Water Data System records collected by the U.S. Geological Survey and cooperating local, State, and Federal agencies in Florida.

Water Data Report↗
USGS2005

Water resources data, Florida, water year 2005. Volume 4: Northwest Florida

This report series for the 2005 water year for the state of Florida consists of records for continuous or daily discharge for 429 streams, periodic discharge for 9 streams, continuous or daily stage for 218 streams, periodic stage for 5 streams, peak stage and discharge for 28 streams, continuous or daily elevations for 15 lakes, periodic elevations for 23 lakes, continuous ground-water levels for 401 wells, periodic ground-water levels for 1,098 wells, and quality-of-water for 211 surface-water sites and 208 wells. This volume (Volume 4, Northwest Florida) contains records of continuous or daily discharge for 76 streams, periodic discharge for 2 streams, continuous or daily stage for 14 streams, periodic stage for 0 streams, peak stage and discharge for 20 streams, continuous or daily elevations for 1 lake, periodic elevations for 0 lakes, continuous ground-water levels for 2 wells, periodic ground-water levels for 0 wells, and quality-of-water for 3 surface-water sites and 0 wells. These data represent the National Water Data System records collected by the U.S. Geological Survey and cooperating local, State, and Federal agencies in Florida.

Water Data Report↗
USGS2000

Water Resources Data: Hawaii and Other Pacific Areas, Water Year 1999. Volume 1. Hawaii

This report includes records on both surface and ground water in the State. Specifically, it contains: (1) Discharge records for 74 stream-gaging stations, 71 miscellaneous streamflow stations, and 88 crest-stage partial-record streamflow stations; (2) water-quality records for 6 streamflow-gaging stations, and 28 partial-record streamflow stations; (3) water-level records for 84 observation wells; (4) water-quality records for 122 observation wells; and (5) accumulated rainfall records for 40 rainfall stations. This series of annual reports for Hawaii began with the 1961 fiscal year (State of Hawaii) with a report that contained only data relating to the quantities of surface water. For the 1964 fiscal year, a similar report was introduced that contained only data relating to water quality. Beginning with the 1975 water year, the report format was changed to include, in one volume, data on quantities of surface water, quality of surface and ground water, and ground-water levels. Beginning with the 1993 water year, accumulated rainfall data were included in the report.

Water Data Report↗
USGS2006

Water resources data, Puerto Rico and the U.S. Virgin Islands, water year 2004

The Caribbean Water Science Center of the U.S. Geological Survey (USGS), in cooperation with local and Federal agencies obtains a large amount of data pertaining to the water resources of the Commonwealth of Puerto Rico and the Territory of the U.S. Virgin Islands each water year. These data, accumulated during many water years, constitute a valuable data base for developing an improved understanding of the water resources of the area. To make these data readily available to interested parties outside the U.S. Geological Survey, the data are published annually in this report series entitled 'Water Resources Data for Puerto Rico and the U.S. Virgin Islands.' This report includes records on both surface and ground water. Specifically, it contains: (1) discharge records for 89 streamflow-gaging stations, daily sediment records for 13 sediment stations, stage records for 18 reservoirs, and (2) water-quality records for 20 streamflow-gaging stations, and for 38 ungaged stream sites, 13 lake sites, 2 lagoons, and 1 bay, and (3) water-level records for 72 observation wells. Water-resources data for Puerto Rico for calendar years 1958-67 were released in a series of reports entitled 'Water Records of Puerto Rico.' Water-resources data for the U.S. Virgin Islands for the calendar years 1962-69 were released in a report entitled 'Water Records of U.S. Virgin Islands.' Included were records of streamflow, ground-water levels, and water-quality data for both surface and ground water. Beginning with the 1968 calendar year, surface-water records for Puerto Rico were released separately on an annual basis. Ground-water level records and water-quality data for surface and ground water were released in companion reports covering periods of several years. Data for the 1973-74 reports were published under separate covers. Water-resources data reports for 1975 to 2003 water years consist of one volume each and contain data for streamflow, water quality, and ground water.

Water Data Report↗