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At least 1,441 records · Page 80Linked to original sources
USGS2010

Groundwater-flow assessment of the Mississippi River Valley alluvial aquifer of northeastern Arkansas

The Mississippi River Valley alluvial aquifer is a water-bearing assemblage of gravels and sands that underlies about 32,000 square miles of Arkansas, Kentucky, Louisiana, Mississippi, Missouri, and Tennessee. Pumping of groundwater from the alluvial aquifer for agriculture started in the early 1900s in the Grand Prairie area for the irrigation of rice and soybeans. From 1965 to 2005, water use in the alluvial aquifer increased 655 percent. In 2005, 6,242 million gallons per day of water were pumped from the aquifer, primarily for irrigation and fish farming. Water-level declines in the alluvial aquifer were documented as early as 1927. Long-term water-level measurements in the alluvial aquifer show an average annual decline of 1 foot per year in some areas. In this report, the utility of the updated 2009 MODFLOW groundwater-flow model of the alluvial aquifer in northeastern Arkansas was extended by performing groundwater-flow assessments of the alluvial aquifer at specific areas of interest using a variety of methods. One such area is along the western side of Crowleys Ridge, which includes western parts of Clay, Greene, Craighead, Poinsett, Cross, St. Francis, and Lee Counties. This area was designated as the Cache Critical Groundwater Area by the Arkansas Natural Resources Commission in 2009 for the alluvial and Sparta/Memphis aquifers, because of the rate of change in groundwater levels and groundwater levels have dropped below half the original saturated thickness of the alluvial aquifer.

Scientific Investigations Report↗
USGS2021

Methods for estimating regional skewness of annual peak flows in parts of eastern New York and Pennsylvania, based on data through water year 2013

Bulletin 17C (B17C) recommends fitting the log-Pearson Type III (LP−III) distribution to a series of annual peak flows at a streamgage by using the method of moments. The third moment, the skewness coefficient (or skew), is important because the magnitudes of annual exceedance probability (AEP) flows estimated by using the LP–III distribution are affected by the skew; interest is focused on the right-hand tail of the distribution, which represents the larger annual peak flows that correspond to small AEPs. For streamgages having modest record lengths, the skew is sensitive to extreme events like large floods, which cause a sample to be highly asymmetrical or “skewed.” For this reason, B17C recommends using a weighted-average skew computed from the skew of the annual peak flows for a given streamgage and a regional skew. This report presents an estimate of regional skew for a study area encompassing parts of eastern New York and Pennsylvania. A total of 232 candidate U.S. Geological Survey streamgages that were unaffected by extensive regulation, diversion, urbanization, or channelization were considered for use in the skew analysis; after screening for redundancy and pseudo record length ( P RL ) of at least 36 years, 183 streamgages were selected for use in the study. Flood frequencies for candidate streamgages were analyzed by employing the expected moments algorithm, which extends the method of moments so that it can accommodate interval, censored, and historical/paleo flow data, as well as the multiple Grubbs-Beck test to identify potentially influential low floods in the data series. Bayesian weighted least squares/Bayesian generalized least squares regression was used to develop a regional skew model for the study area that would incorporate possible variables (basin characteristics) to explain the variation in skew in the study area. Ten basin characteristics were considered as possible explanatory variables; however, none produced a pseudo coefficient of determination greater than 1 percent; as a result, these characteristics did not help to explain the variation in skew in the study area. Therefore, a constant model that had a regional skew coefficient of 0.32 and an average variance of prediction at a new streamgage ( AVP new , which corresponds to the mean square error [MSE] of 0.11) was selected. The AVP new corresponds to an effective record length of 68 years, a marked improvement over the Bulletin 17B national skew map, whose reported MSE of 0.302 indicated a corresponding effective record length of only 17 years.

New York, Pennsylvania↗
USGS2003

Quality-control results for ground-water and surface-water data, Sacramento River Basin, California, National Water-Quality Assessment, 1996-1998

Evaluating the extent that bias and variability affect the interpretation of ground- and surface-water data is necessary to meet the objectives of the National Water-Quality Assessment (NAWQA) Program. Quality-control samples used to evaluate the bias and variability include annual equipment blanks, field blanks, field matrix spikes, surrogates, and replicates. This report contains quality-control results for the constituents critical to the ground- and surface-water components of the Sacramento River Basin study unit of the NAWQA Program. A critical constituent is one that was detected frequently (more than 50 percent of the time in blank samples), was detected at amounts exceeding water-quality standards or goals, or was important for the interpretation of water-quality data. Quality-control samples were collected along with ground- and surface-water samples during the high intensity phase (cycle 1) of the Sacramento River Basin NAWQA beginning early in 1996 and ending in 1998. Ground-water field blanks indicated contamination of varying levels of significance when compared with concentrations detected in environmental ground-water samples for ammonia, dissolved organic carbon, aluminum, and copper. Concentrations of aluminum in surface-water field blanks were significant when compared with environmental samples. Field blank samples collected for pesticide and volatile organic compound analyses revealed no contamination in either ground- or surface-water samples that would effect the interpretation of environmental data, with the possible exception of the volatile organic compound trichloromethane (chloroform) in ground water. Replicate samples for ground water and surface water indicate that variability resulting from sample collection, processing, and analysis was generally low. Some of the larger maximum relative percentage differences calculated for replicate samples occurred between samples having lowest absolute concentration differences and(or) values near the reporting limit. Surrogate recoveries for pesticides analyzed by gas chromatography/mass spectrometry (GC/MS), pesticides analyzed by high performance liquid chromatography (HPLC), and volatile organic compounds in ground- and surface-water samples were within the acceptable limits of 70 to 130 percent and median recovery values between 82 and 113 percent. The recovery percentages for surrogate compounds analyzed by HPLC had the highest standard deviation, 20 percent for ground-water samples and 16 percent for surface-water samples, and the lowest median values, 82 percent for ground-water samples and 91 percent for surface-water samples. Results were consistent with the recovery results described for the analytical methods. Field matrix spike recoveries for pesticide compounds analyzed using GC/MS in ground- and surface-water samples were comparable with published recovery data. Recoveries of carbofuran, a critical constituent in ground- and surface-water studies, and desethyl atrazine, a critical constituent in the ground-water study, could not be calculated because of problems with the analytical method. Recoveries of pesticides analyzed using HPLC in ground- and surface-water samples were generally low and comparable with published recovery data. Other methodological problems for HPLC analytes included nondetection of the spike compounds and estimated values of spike concentrations. Recovery of field matrix spikes for volatile organic compounds generally were within the acceptable range, 70 and 130 percent for both ground- and surface-water samples, and median recoveries from 62 to 127 percent. High or low recoveries could be related to errors in the field, such as double spiking or using spike solution past its expiration date, rather than problems during analysis. The methodological changes in the field spike protocol during the course of the Sacramento River Basin study, which included decreasing the amount of spike solu

Water-Resources Investigations Report↗
USGS1980

Hydrologic analysis of the proposed Badger-Beaver Creeks artificial-recharge project: Morgan County, Colorado

A hydrologic analysis of the proposed Badger-Beaver Creeks artificial-recharge project in Morgan County, Colo., was made with the aid of three digital computer models: A canal-distribution model, a ground-water flow model, and a stream-aquifer model. Statistical summaries of probable diversions from the South Platte River based on a 27-year period of historical flows indicate that an average-annual diversion of 96,000 acre-feet and a median-annual diversion of 43,000 acre-feet would be available. Diversions would sustain water in ponds for waterfowl habitat for an average of about five months per year, with a miximum pond surface area of about 300 acres with the median diversions and a maximum pond surface area of about 1,250 acres at least one-half of the years with the historic diversions. If the annual diversion were 43,000 acre-feet, recharge to the two alluvial aquifers would raise water levels sufficiently to create flowing streams in the channels of Beaver and Badger Creeks while allowing an increase in current ground-water pumping. The only area of significant waterlogging would be along the proposed delivery canal on the west edge of Badger Creek valley. If the total water available were diverted, the aquifer system could not transmit the water fast enough to the irrigation areas to avoid considerable waterlogging in the recharge areas. The impact of the proposed project on the South Platte River basin would be minimal once the ground-water system attained steady-state conditions, but that may take decades with a uniform diversion of the 43,000 acre-feet annually.

Colorado↗
USGS1986

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

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

Water-Resources Investigations Report↗
USGS1993

Contribution of return flows to streamflow in selected stream reaches in Illinois, 1988-89

Water returns by sewage-treatment plants and various water users can be a significant part of streamflow. Knowledge of the effect of return flows on stream- flow is needed for purposes of assessing streamwater quality and water supply. The results of a study by the U.S. Geological Survey, in cooperation with the Illinois Environmental Protection Agency, are presented to describe the contribution of return flows to streamflow for five stream reaches in Illinois during 1988-89. The reaches studied were South Branch Kishwaukee River upstream from De Kaib, Mackinaw River upstream from Congerville, Addison Creek upstream from Bellwood, Flag Creek upstream from Willow Springs, and Thorn Creek upstream from Glenwood. The annual average contributions of return flows to streamflow in each reach ranged from 1 to 99 percent of the annual average streamflow. Return flows significantly affected streamflows in the Flag Creek and Thorn Creek reaches. Significant return flows probably sustained streamflows in the Addison Creek, Flag Creek, and Thorn Creek reaches. Return flows exceeded streamflow during at least 1 month during the 1988 drought at all of the study reaches, except the Thorn Creek reach. Of the amount of return flows that exceeded streamflow, all reaches lost an estimated 0.01 to 0.34 Mgal/d (million gallons per day) to evaporation and 0.36 to 1.33 Mgal/d to infiltration. An analysis-of-variance test indicated that return flows did not differ among seasons. A second analysis indicated that the proportion of return flows to streamflow did differ seasonally. Return flows during July through September 1988-89 constituted a large proportion (67 percent) of the annual streamflows.

Water-Resources Investigations Report↗
USGS2006

Fate of fish production in a seasonally flooded saltmarsh

Although saltmarshes are thought to enhance the productivity of open estuarine waters, the mechanism by which energy transfer occurs has been debated for decades. One possible mechanism is the transfer of saltmarsh production to estuarine waters by vagile fishes and invertebrates. Monthly estimates of fish standing stock, net fish ingress, and predation were used to develop a biomass budget to estimate annual production of fishes and the relative yield to predatory fish, birds, and direct migration to the estuary. Annual production of saltmarsh fishes was estimated to be 31.0 g m-2 saltmarsh, which falls within the range of previously reported values for estuarine fish communities. The relative yields were 12 to 20% to piscivorous fishes, 8 to 13% to piscivorous birds, and 18 to 29% to export. Annual export of fish biomass was 5.6 g fish m-2 saltmarsh, representing about 1 to 2% of saltmarsh primary production. Saltmarsh fishes convert marsh production to high-quality vagile biomass (fishes concentrate energy, protein, and nutrients as body mass) and move this readily useable production to the estuary, providing an efficient link between saltmarshes and estuarine predators. ?? Inter-Research 2006.

Marine Ecology Progress Series↗
USGS2011

Suspended-sediment and suspended-sand concentrations and loads for selected streams in the Mississippi River Basin, 1940-2009

This report presents suspended-sediment concentration and streamflow data, describes load-estimation techniques used in the computation of annual suspended-sediment loads, and presents annual suspended-sediment loads for 48 streamgaging stations within the Mississippi River Basin. Available published, unpublished, and computed annual total suspended-sediment and suspended-sand loads are presented for water years 1940 through 2009. When previously published annual loads were not available, total suspended-sediment and sand loads were computed using available data for water years 1949 through 2009. A table of suspended-sediment concentration and daily mean streamflow data used in the computation of annual loads is presented along with a table of compiled and computed annual suspended-sediment and suspended-sand loads, annual streamflows, and flow-weighted concentrations for the 48 stations.

Data Series↗
USGS1989

Summary of fluvial-sediment studies in Ohio, through 1987

The U.S. Geological Survey, in cooperation with other Federal, State, and local agencies, has been collecting fluvial sediment data from Ohio streams since April 1950. This report summarizes the data collected for the period April 1950 through 1987. In addition, trends in annual suspended-sediment discharge in Ohio streams are examined and discussed, and a technique is presented for estimating discharge at ungaged points on Ohio streams. (USGS)

Water-Resources Investigations Report↗
USGS2025

Potential risks of vegetation treatments to introduce and increase invasive annual grasses in rangelands of Montana, North Dakota, and South Dakota— A science synthesis to inform National Environmental Policy Act analyses

The U.S. Geological Survey is working with Federal land management agencies to develop a series of planned structured science syntheses to support environmental effects analyses that agencies conduct under the National Environmental Policy Act (NEPA). This report synthesizes science information relevant to environmental effects analyses concerned with potential increases in the distribution and abundance of invasive annual grasses (IAGs) from proposed vegetation treatments for habitat restoration. The focal environments for this synthesis are rangelands in the intermontane valleys of Montana and the northern Great Plains of Montana, North Dakota, and South Dakota. The synthesis is organized to align with the standard elements of NEPA analyses and provides information on relevant scientific studies, data availability, analysis methods, and mitigation measures. We found that the likelihood of increasing IAGs from vegetation treatments depends on treatment type and environmental context. In sagebrush ecosystems of the focal region, prescribed fire often reduces or does not increase IAGs. Treatments that cause soil disturbances, such as mechanical removals of sagebrush or firebreak constructions, are more likely to increase IAGs than other treatments. Herbicides applied to reduce sagebrush cover have not increased the proportion of IAGs in the plant community. Temperature and precipitation have been strong factors in determining IAG responses to vegetation treatments in sagebrush ecosystems of the focal region, where more precipitation in spring and summer likely provides a competitive edge to native, perennial grasses more than winter annual grasses like Bromus tectorum L. (cheatgrass). In grasslands, prescribed fire often reduces IAGs, but effects depend on the abundance of native species and are often short lived. Mowing can increase or decrease IAGs in grassland ecosystems. Grassland site conditions, such as southeast-facing slopes, sandier or rockier sites, or lower native species cover or richness affect the likelihood of invasion by annual grasses. Maintaining adequate cover of perennial vegetation creates rangelands that are resistant and resilient to annual grass invasions. Managers can minimize invasion potential by focusing on treatment type, placement, and seasonal timing. Herbicides also can provide effective mitigation, especially in combination with other controls such as prescribed fire or grazing. This report can be incorporated by reference in NEPA documentation, included in a project record, or provide a general reference for understanding and identifying literature about increases in IAGs associated with vegetation treatments in rangelands in this focal region.

Montana, North Dakota, South Dakota↗
USGS1981

Flood peaks and discharge summaries in the Delaware River basin

Streamflow data from 299 continuous and crest-stage sites in the Delaware River basin are summarized in this report. The location, drainage area, period of record, type of gage, and average discharge for each gaging site are given. Also included are tables of annual peaks and peaks above base, annual and monthly means, and annual and monthly runoff.

Delaware, Maryland, New Jersey, New York, Pennsylv↗
USGS2003

Water resources of Monroe County, New York, water years 1997-99, with emphasis on water quality in the Irondequoit Creek basin—Atmospheric deposition, ground water, streamflow, trends in water quality, and chemical loads to Irondequoit Bay

Irondequoit Creek drains 169 square miles in the eastern part of Monroe County. Over time, nutrients transported by Irondequoit Creek to Irondequoit Bay on Lake Ontario have contributed to the eutrophication of the bay. Sewage-treatment-plant effluent, a major source of nutrients to the creek and its tributaries, was eliminated from the basin in 1979 by diversion to a regional wastewater-treatment facility, but sediment and contaminants from nonpoint sources continue to enter the creek and Irondequoit Bay. This report, the fourth in a series of reports that present interpretive analyses of the hydrologic data collected in Monroe County since 1984, interprets data from four surface-water monitoring sites in the Irondequoit Creek basin—Irondequoit Creek at Railroad Mills, East Branch Allen Creek at Pittsford, Allen Creek near Rochester, and Irondequoit Creek at Blossom Road. It also interprets data from three sites in the the Genesee River basin—Oatka Creek at Garbutt, Honeoye Creek at Honeoye Falls, and Black Creek at Churchville—as well as the Genesee River at Charlotte Pump Station, and also from a site on Northrup Creek at North Greece. The Northrup Creek site drains a 23.5-square-mile basin in western Monroe County, and provides information on surface-water quality in streams west of the Genesee River and on loads of nutrients delivered to Long Pond, a small eutrophic embayment of Lake Ontario. The report also includes water-level and water-quality data from nine observation wells in Ellison Park, and atmospheric-deposition data from a collection site at Mendon Ponds County Park. Average annual loads of some chemical constituents in atmospheric deposition for 1997–99 differed considerably from those for the long-term period 1984–96. Ammonia and potassium loads for 1997-99 were 144 and 118 percent greater, respectively, than for the previous period. Sodium and ammonia + organic nitrogen loads were 87 and 60 percent greater, respectively. Average annual loads of sulfate and orthophosphate for 1997-99 were 36 and 30 percent lower, respectively, than for the previous period. Loads of all nutrients deposited on the Irondequoit basin from atmospheric sources during 1997–99 greatly exceeded those transported by Irondequoit Creek. The ammonia load deposited on the basin was 139 times the load transported at Blossom Road (the most downstream site); the ammonia + organic nitrogen load was 6.3 times greater, orthophosphate 7.5 times greater, total phosphorus 1.3 times greater and nitrite + nitrate 1.5 times greater. Average yields of dissolved chloride and dissolved sulfate from atmospheric sources were much smaller than those transported by streamflow at Blossom Road.chloride was about 2 percent and sulfate about 8 percent of the amount transported. Trends in concentration of chemical constituents in surface water generally can be attributed to changes in land use, annual and seasonal variations in streamflow, and annual variations in the application of road salt to county highways and roads. Concentrations of several constituents in streams of the Irondequoit Creek basin showed statistically significant (α=0.05) trends from the beginning of their period of record through 1999. The constituent with the greatest number of significant trends was ammonia + organic nitrogen, with downward trends ranging from 4.1 to 5.6 percent per year at Allen Creek, Irondequoit Creek at Blossom Road, and East Branch Allen Creek. Orthophosphate showed an upward trend of 4.1 percent per year at Irondequoit Creek at Railroad Mills (the most upstream site). Dissolved chloride showed upward trends at Railroad Mills, Allen Creek, and Blossom Road. No trends in volatile suspended solids were noted at any of the four Irondequoit basin sites. Northrup Creek showed significant downward trends in concentrations of ammonia + organic nitrogen (3.3 percent per year), total phosphorus (3.4 percent per year), and orthophosphate (5.5 percent per year), and an upward trend for dissolved sulfate (1.8 percent per year). The Genesee River at Charlotte Pump Station showed downward trends of 6.1 percent per year for ammonia + organic nitrogen and 0.1 percent per year for chloride, and upward trends of 1.7 percent per year for total phosphorus and 6.6 percent per year for orthophosphate. Mean annual yields (mass per unit area) of most constituents at the Irondequoit Creek basin sites were similar to those noted for the previous report period (1994–96). East Branch Allen Creek showed lower yields of all constituents during 1997–99 than previously, even though runoff during 1997–99 was greater. These lower yields are attributed to the construction of an upstream detention basin on East Branch Allen Creek in 1995. Statistical analysis of long-term (greater than 12 years) streamflow records for unregulated streams in Monroe County indicated that annual mean flows for water years 1997–99 were in the normal range (75th to 25th percentile), although Allen Creek continues to show a significant downward trend in mean monthly streamflow during the 1984–99 water years.

New York↗
USGS2022

Stormwater quantity and quality in selected urban watersheds in Hampton Roads, Virginia, 2016–2020

Urbanization can substantially alter sediment and nutrient loadings to streams. Although a growing body of literature has documented these processes, conditions may vary widely by region and physiographic province (PP). Substantial investments are made by localities to meet federal, state, and local water-quality goals and locally relevant monitoring data are needed to appropriately set standards and track progress. In 2016, a long-term stormwater monitoring program was initiated to characterize water-quality and streamflow conditions and compute average annual nutrient- and sediment-loading rates across the three dominant land-use types—commercial (COM), high-density residential, and single-family residential (SFR)—in the Hampton Roads metropolitan region within the Coastal Plain PP in southeastern Virginia. This report summarizes the first five years of data collection to (1) assess patterns in streamflow and water chemistry across the three major land-use types in the region; (2) compute annual sediment and nutrient loads; and (3) compare annual loading rates to those in other urbanized regions. Patterns in watershed hydrology characteristics and conditions were similar to those observed in other urban monitoring studies. Base-flow indices were lower and stream flashiness indices were higher in the study watersheds compared to those in less developed reference watersheds. These patterns reflect a decrease in infiltration and consequent increase in storm runoff as a result of urbanization. Stream flashiness was strongly positively related to degree of impervious land cover and negatively to watershed area. Hydrologic metrics varied across the land-use gradient, reflecting greater and more rapid runoff in the COM watersheds than in SFR watersheds. Event-based analyses conducted exclusively on periods of runoff highlight longer duration events, longer time-to-peak streamflow, and a longer lag between peak precipitation and peak streamflow in SFR watersheds, and higher stormflow yields, runoff ratios, and peak flows in COM watersheds. Event-based metrics varied seasonally because of regional meteorological patterns. Concentrations of total suspended solids (TSS) and total phosphorus (TP) were positively correlated to streamflow, whereas concentrations of total nitrogen (TN) varied little across the hydrologic regime. Phosphorus composition varied spatially and seasonally—the proportion of orthophosphate (PO 4 3- ) was highest in samples collected from stations draining residential land-use types and was elevated in summer and fall. Nitrogen composition varied with hydrologic condition: nitrate plus nitrite (NO 3 - ) dominance during base flow shifted to total organic nitrogen (TON) dominance during periods of runoff. For all three major constituents (TSS, TP, and TN), concentrations were highest in SFR watersheds, whereas yields were greatest in COM watersheds. This seeming contradiction in concentration and yield across land-use types occurred because of spatial differences in streamflow yield. The network average TSS yield in Hampton Roads was lower than that in comparable networks in Fairfax County, Virginia, and Gwinnett County, Georgia, a difference that may reflect dissimilarities in the topographic and soil characteristics of the Coastal Plain versus those in Piedmont PPs, as well as differences in engineered concrete stormwater conveyances versus earthen streams. The average annual TP yield in Hampton Roads was higher than averages reported in comparison studies and was primarily driven by elevated PO 4 3- . Elevated PO 4 3- yields may be related to unique soil and geological features of the Coastal Plain PP that limit phosphorus retention. Total nitrogen yields in the Hampton Roads and Fairfax County networks were similar; however, composition did vary, with greater total organic nitrogen yields in Hampton Roads and greater NO 3 - yields in Fairfax County. Cross-correlation analyses and mass-volume curves were used to assess the timing of sediment and nutrient loadings. The majority of TSS and TP was typically transported during the initial phase of a storm-runoff event, a phenomenon commonly termed the “first flush.” Although TN concentrations typically peaked within an hour of peak streamflow, reflecting the particulate dominance of TN during stormflows, and loadings were greater during the early phase of most storm events, the stricter first-flush criterion was rarely met. This suggests that the most abundant sources of TN in these watersheds are not as directly connected to the stormwater-conveyance system as are TSS and TP.

Virginia↗
USGS2012

Simulation of groundwater and surface-water resources and evaluation of water-management alternatives for the Chamokane Creek basin, Stevens County, Washington

A three-dimensional, transient numerical model of groundwater and surface-water flow was constructed for Chamokane Creek basin to better understand the groundwater-flow system and its relation to surface-water resources. The model described in this report can be used as a tool by water-management agencies and other stakeholders to quantitatively evaluate the effects of potential increases in groundwater pumping on groundwater and surface-water resources in the basin. The Chamokane Creek model was constructed using the U.S. Geological Survey (USGS) integrated model, GSFLOW. GSFLOW was developed to simulate coupled groundwater and surface-water resources. The model uses 1,000-foot grid cells that subdivide the model domain by 102 rows and 106 columns. Six hydrogeologic units in the model are represented using eight model layers. Daily precipitation and temperature were spatially distributed and subsequent groundwater recharge was computed within GSFLOW. Streamflows in Chamokane Creek and its major tributaries are simulated in the model by routing streamflow within a stream network that is coupled to the groundwater-flow system. Groundwater pumpage and surface-water diversions and returns specified in the model were derived from monthly and annual pumpage values previously estimated from another component of this study and new data reported by study partners. The model simulation period is water years 1980-2010 (October 1, 1979, to September 30, 2010), but the model was calibrated to the transient conditions for water years 1999-2010 (October 1, 1998, to September 30, 2010). Calibration was completed by using traditional trial-and-error methods and automated parameter-estimation techniques. The model adequately reproduces the measured time-series groundwater levels and daily streamflows. At well observation points, the mean difference between simulated and measured hydraulic heads is 7 feet with a root-mean-square error divided by the total difference in water levels of 4.7 percent. Simulated streamflow was compared to measured streamflow at the USGS streamflow-gaging station-Chamokane Creek below Falls, near Long Lake (12433200). Annual differences between measured and simulated streamflow for the site ranged from -63 to 22 percent. Calibrated model output includes a 31-year estimate of monthly water budget components for the hydrologic system. Five model applications (scenarios) were completed to obtain a better understanding of the relation between groundwater pumping and surface-water resources. The calibrated transient model was used to evaluate: (1) the connection between the upper- and middle-basin groundwater systems, (2) the effect of surface-water and groundwater uses in the middle basin, (3) the cumulative impacts of claims registry use and permit-exempt wells on Chamokane Creek streamflow, (4) the frequency of regulation due to impacted streamflow, and (5) the levels of domestic and stockwater use that can be regulated. The simulation results indicated that streamflow is affected by existing groundwater pumping in the upper and middle basins. Simulated water-management scenarios show streamflow increased relative to historical conditions as groundwater and surface-water withdrawals decreased.

Washington↗
USGS1969

Hydrogeologic data for the southwestern coastal river basins, Connecticut

This report presents hydrologic and geologic data collected by the U.S. Geological Survey during an investigation of water resources in the southwestern coastal river basins of Connecticut in cooperation with the Connecticut Water Resources Commission. These basins occupy about 394 square miles in Connecticut and 46 square miles in New York, including the towns of Greenwich, Stamford, Darien, New Canaan, Norwalk, Wilton, Westport, Weston, Fairfield, Easton, and Bridgeport and parts of Danbury, Ridgefield, Redding, Bethel, Newtown, Trumbull, Monroe, Shelton, and Stratford. A companion interpretive report evaluating the water resources of the basins will be published as Connecticut Water Resources Bulletin No. 17. The data on the following pages serve to document and supplement that report and should be especially useful in planning the development of water resources at specific localities. Data were collected as part of this investigation during the period July 1963 through November 1966. Streamflow records from continuous-record gaging stations in the basins have been published annually along with data from other parts of the State in a series of U.S. Geological Survey reports entitled "Surface Water Records of Connecticut." Water-level measurements in wells throughout the State from 1960 through 1966, including most of those made as part of this investigation, are published in Connecticut Water Resources Bulletins No. 7 and No. 13. Most other data collected during this investigation are tabulated on the following pages. Included are some well records and chemical analyses of water samples collected prior to July 1963 and not previously published. The locations of sites at which data were collected are shown on plate A in the pocket at the back of the report. Data presented, unless otherwise noted, were collected by U.S. Geological Survey personnel.

Connecticut↗
USGS1980

Waterfowl status report, 1976

This report contains information from the 1975-76 midwinter waterfowl survey, the 1976 waterfowl breeding population and production surveys, and the waterfowl harvest surveys for the 1975-76 hunting season. This information was provided by the U.S. Fish and Wildlife Service, the Canadian Wildlife Service, and various cooperating State wildlife conservation agencies. Winter surveys are composed of the midwinter survey reports submitted from each of the four flyways and the midwinter survey covering a portion of the west coast of Mexico. The breeding ground surveys section is composed of many individual reports that provide breeding population and production estimates for most waterfowl species within a major portion of their breeding range. The waterfowl harvest survey provides estimates of waterfowl hunting activity and success. Information from surveys of the wintering and breeding populations of waterfowl, coupled with data from the annual harvest survey, are instrumental in developing annual hunting regulations for waterfowl. Credit has been given to each individual or organization that submitted a report. Although some of the narrative statements have been condensed and a few tables deleted or condensed if they contain data presented elsewhere in this report, the essential information from each report has been retained. The breeding grounds survey strata (Fig. 1) for areas surveyed by Fish and Wildlife Service crews were renumbered in 1974.

Special Scientific Report - Wildlife↗
USGS1967

Hydrogeologic data for the Shetucket River basin, Connecticut

This report presents hydrologic and geologic data collected by the U.S. Geological Survey during an investigation of water resources in the Shetucket River basin of Connecticut in cooperation with the Connecticut Water Resources Commission. The Shetucket River basin occupies about 507 square miles in the eastern part of the State, including the towns of Andover, Ashford, Chaplin, Coventry, Mansfield, Scotland, Sprague, Windham, and Willington, and parts of Bolton, Canterbury, Columbia, Eastford, Ellington, Franklin, Lebanon, Lisbon, Hampton, Hebron, Norwich, Pomfret, Stafford, Tolland, Union, Vernon, and Woodstock. A companion interpretive report, Connecticut Water Resources Bulletin ll, (Thomas, and others, 1967), evaluates the water resources of the basin. The data on the following pages serve to document and supplement that report and should be especially useful in planning the development of water resources at specific localities. Data were collected as part of this investigation during the period July 1962 through December 1964. Streamflow records from continuous-record gaging stations in the basin for this period have been published annually along with data from other parts of the State in a series of U.S. Geological Survey reports entitled "Surface Water Records of Connecticut." Water-level measurements in wells throughout the State from 1960 through 1964, including those made as part of this investigation, are published in Connecticut Water Resources Bulletin 7 (Meikle and Baker, 1965). Most other data collected during this investigation are tabulated on the following pages. Included are some well records and chemical analyses of water samples collected prior to July 1962 and not previously published. The locations of sites at which data were collected are shown on plate A in the pocket at the back of the report. Plate A includes the locations of 98 sites where 2 to 6 miscellaneous measurements of streamflow were made during 1963 and 13 other sites where continuous records are maintained. Data for these sites have already been published in "Surface Water Records of Connecticut" and are not repeated here. Data presented~ unless otherwise noted, were collected by U.S. Geological Survey personnel.

Connecticut↗
USGS2017

Low-flow characteristics of streams in South Carolina

An ongoing understanding of streamflow characteristics of the rivers and streams in South Carolina is important for the protection and preservation of the State’s water resources. Information concerning the low-flow characteristics of streams is especially important during critical flow periods, such as during the historic droughts that South Carolina has experienced in the past few decades. Between 2008 and 2016, the U.S. Geological Survey, in cooperation with the South Carolina Department of Health and Environmental Control, updated low-flow statistics at 106 continuous-record streamgages operated by the U.S. Geological Survey for the eight major river basins in South Carolina. The low-flow frequency statistics included the annual minimum 1-, 3-, 7-, 14-, 30-, 60-, and 90-day mean flows with recurrence intervals of 2, 5, 10, 20, 30, and 50 years, depending on the length of record available at the streamflow-gaging station. Computations of daily mean flow durations for the 5-, 10-, 25-, 50-, 75-, 90-, and 95-percent probability of exceedance also were included. This report summarizes the findings from publications generated during the 2008 to 2016 investigations. Trend analyses for the annual minimum 7-day average flows are provided as well as trend assessments of long-term annual precipitation data. Statewide variability in the annual minimum 7-day average flow is assessed at eight long-term (record lengths from 55 to 78 years) streamgages. If previous low-flow statistics were available, comparisons with the updated annual minimum 7-day average flow, having a 10-year recurrence interval, were made. In addition, methods for estimating low-flow statistics at ungaged locations near a gaged location are described.

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