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At least 847 records · Page 47Linked to original sources
USGS2011

A digital terrain model of bathymetry and shallow-zone bottom-substrate classification for Spednic Lake and estimates of lake-level-dependent habitat to support smallmouth bass persistence modeling

In 2009, the U.S. Geological Survey entered into a cooperative agreement with the International Joint Commission, St. Croix River Board to do an analysis of historical smallmouth bass habitat as a function of lake level for Spednic Lake in an effort to quantify the effects, if any, of historical lake-level management and meteorological conditions (from 1970 to 2009) on smallmouth bass year-class failure. The analysis requires estimating habitat availability as a function of lake level during spawning periods from 1970 to 2009, which is documented in this report. Field work was done from October 19 to 23, and from November 2 to 10, 2009, to acquire acoustic bathymetric (depth) data and acoustic data indicating the character of the surficial lake-bottom sediments. Historical lake-level data during smallmouth bass spawning (May-June) were applied to the bathymetric and surficial-sediment type data sets to produce annual historic estimates of smallmouth-bass-spawning-habitat area. Results show that minimum lake level during the spawning period explained most of the variability (R2 = 0.89) in available spawning habitat for nearshore areas of shallow slope (less than 10 degrees) on the basis of linear correlation. The change in lake level during the spawning period explained most of the variability (R2 = 0.90) in available spawning habitat for areas of steeper slopes (10 to 40 degrees) on the basis of linear correlation. The next step in modeling historic smallmouth bass year-class persistence is to combine this analysis of the effects of lake-level management on habitat availability with meteorological conditions.

Spednic Lake, St. Croix River basin↗
USGS1986

Progress report on the effects of highway construction on suspended-sediment discharge in the Coal River and Trace Fork, West Virginia, 1975-81

Construction of the four-lane Appalachian Corridon G highway disturbed about 2 sq mi in the Coal River and 0.35 sq mi of the 4.75 sq mi Trace Fork basin in southern West Virginia. Construction had a negligible effect on runoff and suspended-sediment load in the Coal River and its major tributaries, the Little Coal and Big Coal Rivers. Drainage areas of the mainstem sites in the Coal River basin ranged from 269 to 862 sq mi, and average annual suspended-sediment yields ranged from 535 to 614 tons/sq mi for the 1975-81 water years. Suspended-sediment load in the smaller Trace Fork basin (4.72 sq mi) was significantly affected by the highway construction. Based on data from undisturbed areas upstream from construction, the normal background load at Trace Fork downstream from construction during the period July 1980 to September 1981 was estimated to be 830 tons; the measured load was 2,385 tons. Runoff from the 0.35 sq mi area disturbed by highway construction transported approximately 1,550 tons of sediment. Suspended-sediment loads from the construction zone were also higher than normal background loads during storms. (USGS)

Water-Resources Investigations Report↗
USGS1954

Ground water resources of southeastern Oakland County, Michigan

The area covered by this report comprises a square which measures three townships on a side and enclose 318 square miles in southeastern Oakland County. The investigation of the ground-water resources of this area was made by the U.S. Geological Survey in cooperation with the Detroit Metropolitan Area Regional Planning Commission, the Michigan Department of Conservation, and the Michigan Water Resources Commission. In 1950 the population of this nine-township area exceeded 341,000, or more than 86 percent of the total population of Oakland County. This county ranks third in the state in number of industrial establishments and workers and is fifteenth in agricultural importance. Its numerous lakes and rolling uplands contribute to its top rank in the state in the number of recreational enterprises in rural or suburban areas. The climate is moderately humid. The average annual precipitation is 30 inches and the mean air temperature is 47.2° F. Snowfall averages 38 inches in the November-April interval. The growing season averages 151 days. The regional land surface slopes from northwest to southeast and has a total relief of 360 feet. Pitted outwash plains and morainal hills that are more than 1,000 feet above sea level in the northwest corner of the area give way southeastward to a sequence of terminal moraines and intervening till plains in the middle part. These give way to the broad lake plains that cover the southeastern third of the area. The area lies on the southeast edge of the Michigan Basin and the bedrock is composed of northwest dipping strata of the Devonian and Mississippian systems. The Antrim shale, of Lake Devonian and early Mississippian age, is the oldest formation cropping out beneath the mantle of glacial Berea sandstone, and Sunbury shale overlie the Antrim and are overlain by the Coldwater shale, their areas of outcrop beneath the drift lying successively farther northwest. These formations are of early Mississippian age. Throughout the area the bedrock is covered by glacial drift which ranges in thickness from 25 to more than 350 feet. The drift increases in thickness from southeast to northwest, but considerable relief on the underlying bedrock surface greatly modifies this trend. Extensive moraines, till plains, lake plains, and gravel outwash plains cover the area. In the northwestern third of the area an extensive upland of gravel plains is dotted with lakes ranging from a few feet to more than 100 feet in depth. Precipitation is the perennial source of all water in this area, whether on the surface of underground. The average annual rainfall on the nine-townships is equivalent to a continuous supply of 450 m.g.d. or 9 times the combined annual withdrawal from all wells in the area. About 53 percent of the area is drained by the Clinton River, 44 percent by the River Rouge, and the remaining 3 percent by the Huron River. Less than one-third of the annual precipitation reappears as surface discharge from the watersheds of this area. About two-thirds of the annual precipitation on the area is lost by evaporation from water and land surfaces and by transpirations from vegetative cover. A substantial part of this large annual water loss is from the many lakes and other exposed water surfaces and from contiguous lands where the depth to the water table is slight. Average annual water losses by evapotranspiration are equivalent to about 280 m.g.d. or nearly 6 times the combined withdrawal from all ground-water supplies in the area. The principal aquifers are the alluvial deposits bordering streams and the buried outwash deposits which represent alluvial fills in preglacial or interglacial stream channels. Intensive well developments in the urban areas have greatly lowered ground-water levels in the buried outwash deposits, have brought localized problems of declining well yield, and have induced migration of mineralized waters from the underlying consolidated formations. During 1952, withdrawals of ground water in the nine township area averages about 50 m.g.d., most of this quantity being pumped from municipal wells. This annual pumpage was distributed as follows: 60 percent in Pontiac and environs; 20 percent in Birmingham, Royal Oak and Troy Township; and the remaining 20 percent throughout the suburban and rural areas.

Michigan↗
USGS2010

Potentiometric Surfaces and Water-Level Trends in the Cockfield (Upper Claiborne) and Wilcox (Lower Wilcox) Aquifers of Southern and Northeastern Arkansas, 2009

Eocene-age sand beds near the base of the Cockfield Formation of Claiborne Group constitute the aquifer known locally as the Cockfield aquifer. Upper-Paleocene age sand beds within the lower parts of the Wilcox Group constitute the aquifer known locally as the Wilcox aquifer. In 2005, reported water withdrawals from the Cockfield aquifer in Arkansas totaled 16.1 million gallons per day, while reported water withdrawals from the Wilcox aquifer in Arkansas totaled 27.0 million gallons per day. Major withdrawals from these units were for industrial and public water supplies with lesser but locally important withdrawals for commercial, domestic, and agricultural uses. During February 2009, 56 water-level measurements were made in wells completed in the Cockfield aquifer and 57 water-level measurements were made in wells completed in the Wilcox aquifer. The results from the 2009 water-level measurements are presented in potentiometric-surface maps and in combination with previous water-level measurements. Trends in water-level change over time within the two aquifers are investigated using water-level difference maps and well hydrographs. Water-level difference maps were constructed for each aquifer using the difference between depth to water measurements made in 2003 to 2009. Well hydrographs for each aquifer were constructed for wells with 20 or more years of historical water-level data. The hydrographs were evaluated individually using linear regression to calculate the annual rise or decline in water levels, and by aggregating the regression results by county and statistically summarizing for the range, mean, and median water-level change in each county. The 2009 potentiometric surface of the Cockfield aquifer map indicates the regional direction of groundwater flow generally towards the east and southeast, except in two areas of intense groundwater withdrawals that have developed into cones of depression. The lowest water-level altitude measured was 43 feet and the highest water-level altitude measured was 351 feet. A water-level difference map was constructed from 54 wells completed in the Cockfield aquifer within Arkansas. The largest rise in water level was 14.9 feet and the largest decline was 27.4 feet. Seven wells had a rise in water level, and the remaining 47 wells had a decline in water level. Hydrographs for 33 wells completed in the Cockfield aquifer were developed. Hydrographs indicate water-level changes in individual wells ranged from rises of 0.33 feet per year to declines of 1.21 feet per year over the 20-year period (1990-2009). County summaries of the linear regression analysis indicate Cleveland and Columbia Counties have mean annual rises. Arkansas, Ashley, Bradley, Calhoun, Chicot, Desha, Drew, Lincoln, and Union Counties have mean annual declines. The potentiometric surface for the Wilcox aquifer is presented using two maps, one for a southern area and another for a northeastern area, because of the absence of water-level data in the central part of the State. The direction of groundwater flow in the southern area is generally the east, except around two cones of depression and around two mounds of elevated water levels. Water-level altitudes in the southern area range from 147 feet to 400 feet. The direction of groundwater flow in the northeastern area is generally to the south and southeast except in an area of intense groundwater withdrawals that has altered the flow to a westerly direction. Two water-level difference maps were constructed using water-level altitudes measured in 2003 to 2009 from 53 wells completed in the Wilcox aquifer within southern and northeastern Arkansas. In the southern area the largest rise in water level was 16.0 feet and the largest decline was 17.7 feet. Eight wells in the southern area had rising water levels and the remaining five wells had declining water levels. In the northeastern area, the largest rise in water level was 1.3 feet and the larg

Scientific Investigations Report↗
USGS2010

Hydrology of Eagle Creek Basin and effects of groundwater pumping on streamflow, 1969-2009

Urban and resort development and drought conditions have placed increasing demands on the surface-water and groundwater resources of the Eagle Creek Basin, in southcentral New Mexico. The Village of Ruidoso, New Mexico, obtains 60-70 percent of its water from the Eagle Creek Basin. The village drilled four production wells on Forest Service land along North Fork Eagle Creek; three of the four wells were put into service in 1988 and remain in use. Local citizens have raised questions as to the effects of North Fork well pumping on flow in Eagle Creek. In response to these concerns, the U.S. Geological Survey, in cooperation with the Village of Ruidoso, conducted a hydrologic investigation from 2007 through 2009 of the potential effect of the North Fork well field on streamflow in North Fork Eagle Creek. Mean annual precipitation for the period of record (1942-2008) at the Ruidoso climate station is 22.21 inches per year with a range from 12.27 inches in 1970 to 34.81 inches in 1965. Base-flow analysis indicates that the 1970-80 mean annual discharge, direct runoff, and base flow were 2,260, 1,440, and 819 acre-ft/yr, respectively, and for 1989-2008 were 1,290, 871, and 417 acre-ft/yr, respectively. These results indicate that mean annual discharge, direct runoff, and base flow were less during the 1989-2008 period than during the 1970-80 period. Mean annual precipitation volume for the study area was estimated to be 12,200 acre-feet. Estimated annual evapotranspiration for the study area ranged from 8,730 to 8,890 acre-feet. Estimated annual basin yield for the study area was 3,390 acre-ft or about 28 percent of precipitation. On the basis of basin-yield computations, annual recharge was estimated to be 1,950 acre-ft, about 16 percent of precipitation. Using a chloride mass-balance method, groundwater recharge over the study area was estimated to average 490 acre-ft, about 4.0 percent of precipitation. Because the North Fork wells began pumping in 1988, 1969-80 represents the pre-groundwater-pumping period, and 1988-2009 represents the groundwater-pumping period. The 5-year moving average for precipitation at the Ruidoso climate station shows years of below-average precipitation during both time periods, but no days of zero flow were recorded for the 11-year period 1970-80 and no-flow days were recorded in 11 of 20 years for the 1988-2009 period. View report for unabridged abstract.

Scientific Investigations Report↗
USGS2010

Nitrogen Loads in Groundwater Entering Back Bays and Ocean from Fire Island National Seashore, Long Island, New York

Fire Island is a barrier island that lies south of central Long Island, N.Y. It is about 60 km (37 mi) long and 0.5 km (1/4 mi) wide and is bounded by the Great South Bay, Narrow Bay, and Moriches Bay estuaries to the north; by the Atlantic Ocean to the south; by Fire Island Inlet to the west; and by Moriches Inlet to the east (fig. 1). Fire Island National Seashore (FIIS) encompasses a 42-km (26-mi) length of Fire Island that is bordered by Robert Moses State Park to the west and Smith Point County Park to the east (fig. 2). Interspersed throughout FIIS are 17 residential beach communities that together contain about 4,100 homes. The barrier island's summer population increases 50-fold through the arrival of summer residents and vacationers. The National Park Service (NPS) has established several facilities on the island to accommodate visitors to FIIS. About 2.2 million people visit at least one of the 17 communities and (or) Smith Point County Park, the waterways surrounding Fire Island, or a FIIS facility annually (National Park Service, 2007). Combined visitation on a peak-season weekend day can be as high as 100,000 (National Park Service, 2002). Most homes and businesses in the 17 barrier-island communities discharge untreated wastewater directly to the shallow (water-table) aquifer through private septic systems and cesspools; the NPS facilities discharge wastewater to this aquifer through leach fields and cesspools. (The community of Ocean Beach (fig. 2) has a treatment plant that discharges to tidewater.) Contaminants in sewage entering the shallow groundwater move through the flow system and are ultimately discharged to adjacent marine surface waters, where they can pose a threat to coastal habitats. A contaminant of major concern is nitrogen, which is derived from fertilizers and human waste. The continuous inflow of nitrogen to surface-water bodies can lead to increased production of phytoplankton and macroalgae, which in turn can cause oxygen depletion, decreases in size of estuarine fish and shellfish communities, and loss of submerged seagrass habitat through light limitation (Valiela and others, 1992). The FIIS boundary extends roughly 1.2 km (0.8 mi) into the back-barrier estuaries of Great South Bay, Narrow Bay, and Moriches Bay (fig. 1). Within this estuarine zone are extensive areas of seagrass, shellfish, and finfish habitat, as well as intense recreational activity (Bokuniewicz and others, 1993). Management strategies for protection of these habitats require data on (1) concentrations and movement of nutrients and other human-derived contaminants that enter the groundwater system from on-site septic systems, and (2) aquifer characteristics and groundwater flow patterns. These data can then be used in three-dimensional flow models of the shallow aquifer system to predict the rates of groundwater discharge to the marine surface waters that bound Fire Island and the concentrations of nitrogen entering these water bodies from the aquifer's discharge zones. In 2004, the U.S. Geological Survey (USGS), in cooperation with the NPS, began a 3-year investigation to (1) measure groundwater levels within four local study areas at FIIS, (2) collect groundwater samples from these areas for nutrient (nitrogen) analysis, (3) develop a three-dimensional model of the hydrologic system and adjacent saltwater bodies for groundwater-flow delineation and particle tracking, and (4) apply the results of groundwater-discharge simulations to calculate the annual nitrogen loads in these discharges, particularly those entering Great South Bay, which together with the other back bays receives an estimated 80 percent of the total groundwater discharge from Fire Island. The four areas on which the investigation focused were the communities of Kismet and Robbins Rest, the NPS Visitor Center at Watch Hill, and the undeveloped Otis Pike Fire Island High Dune Wilderness (shown in panels A, B, C, and D in fig. 2); these were

Open-File Report↗
USGS1998

Surface-water and suspended-sediment inflow and outflow for Nutria Reservoir No. 3, Zuni Indian Reservation, New Mexico, March 1994 to September 1995

Surface-water and suspended-sediment inflow to and outflow from Nutria Reservoir No. 3 on the Zuni Indian Reservation, western New Mexico, were calculated. The period of study was March 3, 1994, to September 30, 1995. Total runoff into Nutria Reservoir No. 3 during the study period was 6,812 acre-feet. During the study period, 24,310 tons of suspended sediment was transported into Nutria Reservoir No. 3, and 259 tons of suspended sediment was transported out of Nutria Reservoir No. 3. Runoff during the study period, recorded at an upstream gage with 25 years of record, was 137 percent higher than that for a 19-month period similar to the study period. This may indicate that suspended-sediment loads transported into Nutria Reservoir No. 3 also were larger than average. Based on the difference between inflow and outflow of suspended sediment, 24,050 tons of suspended sediment was deposited in Nutria Reservoir No. 3. From March 1994 to May 1994 the spillway elevation of Nutria Reservoir No. 3 was raised to allow water to be diverted into an adjacent reservoir, Nutria Reservoir No. 4. This flow and sediment transported into Nutria Reservoir No. 4 were not recorded. If the elevation of the spillway had not been raised, suspended- sediment loads recorded downstream from Nutria Reservoir No. 3 would have been larger and the calculated amount of sediment deposited in Nutria Reservoir would have been smaller. Of the total suspended-sediment load entering Nutria Reservoir No. 3 during the study period, 94 percent was transported by an arroyo, Garcia Draw. Garcia Draw drains only 15 percent of the total drainage area of Nutria Reservoir No. 3 and contributed less than 5 percent of the total surface runoff to the reservoir. The average annual amount of sediment deposited in Nutria Reservoir No. 3 during the study was 15,355 tons. By using a dry-weight density of 99.4 pounds per cubic foot for the deposited sediment, the annual volume of sediment deposited in Nutria Reservoir No. 3 is 7.09 acre-feet per year. This number is smaller than the previously reported sedimentation rate of 15.0 acre-feet per year obtained from past surveys. The capacity of Nutria Reservoir No. 3 in 1993 was 191 acre-feet. By using the calculated average sedimentation rate of 7.09 acre-feet per year, Nutria Reservoir No. 3 could be completely filled approximately 27 years after the 1993 survey.

New Mexico↗
USGS2016

A review of precipitation and temperature control on seedling emergence and establishment for ponderosa and lodgepole pine forest regeneration

The persistence of ponderosa pine and lodgepole pine forests in the 21st century depends to a large extent on how seedling emergence and establishment are influenced by driving climate and environmental variables, which largely govern forest regeneration. We surveyed the literature, and identified 96 publications that reported data on dependent variables of seedling emergence and/or establishment and one or more independent variables of air temperature, soil temperature, precipitation and moisture availability. Our review suggests that seedling emergence and establishment for both species is highest at intermediate temperatures (20 to 25 °C), and higher precipitation and higher moisture availability support a higher percentage of seedling emergence and establishment at daily, monthly and annual timescales. We found that ponderosa pine seedlings may be more sensitive to temperature fluctuations whereas lodgepole pine seedlings may be more sensitive to moisture fluctuations. In a changing climate, increasing temperatures and declining moisture availability may hinder forest persistence by limiting seedling processes. Yet, only 23 studies in our review investigated the effects of driving climate and environmental variables directly. Furthermore, 74 studies occurred in a laboratory or greenhouse, which do not often replicate the conditions experienced by tree seedlings in a field setting. It is therefore difficult to provide strong conclusions on how sensitive emergence and establishment in ponderosa and lodgepole pine are to these specific driving variables, or to investigate their potential aggregate effects. Thus, the effects of many driving variables on seedling processes remain largely inconclusive. Our review stresses the need for additional field and laboratory studies to better elucidate the effects of driving climate and environmental variables on seedling emergence and establishment for ponderosa and lodgepole pine.

Forest Ecology and Management↗
USGS1987

Some aspects of U.S. Geological Survey activities related to the effects of contaminants on water resources

The U.S. Geological Survey 's water resources programs are supported by direct annual appropriations from Congress, the Federal-State Cooperative Program (50:50 matching of funds), and by funds provided by other Federal agencies. For fiscal year 1987, total obligations exceeded $250 million for activities in every State, Puerto Rico, and several territories in cooperation with nearly 1,000 local, State, regional, and other Federal agencies. The quality of the ground and surface waters has been of concern to the Geological Survey from the time it was established. During the past few years, water resources contamination has received highest priority consideration and a variety of investigations and research are ongoing to obtain an improved understanding of the Nation 's water quality and the factors affecting it. This report presents information on program priorities and discusses the coordinated activities focusing on the effects of contaminants on water resources. The report also describes a number of investigations and research activities in progress during fiscal years of 1986 and 1987, and provides guidance on how to obtain additional details. (Author 's abstract)

Open-File Report↗
USGS2010

Simulation of streamflow, evapotranspiration, and groundwater recharge in the lower San Antonio River Watershed, South-Central Texas, 2000-2007

The U.S. Geological Survey (USGS), in cooperation with the San Antonio River Authority, the Evergreen Underground Water Conservation District, and the Goliad County Groundwater Conservation District, configured, calibrated, and tested a watershed model for a study area consisting of about 2,150 square miles of the lower San Antonio River watershed in Bexar, Guadalupe, Wilson, Karnes, DeWitt, Goliad, Victoria, and Refugio Counties in south-central Texas. The model simulates streamflow, evapotranspiration (ET), and groundwater recharge using rainfall, potential ET, and upstream discharge data obtained from National Weather Service meteorological stations and USGS streamflow-gaging stations. Additional time-series inputs to the model include wastewater treatment-plant discharges, withdrawals for cropland irrigation, and estimated inflows from springs. Model simulations of streamflow, ET, and groundwater recharge were done for 2000-2007. Because of the complexity of the study area, the lower San Antonio River watershed was divided into four subwatersheds; separate HSPF models were developed for each subwatershed. Simulation of the overall study area involved running simulations of the three upstream models, then running the downstream model. The surficial geology was simplified as nine contiguous water-budget zones to meet model computational limitations and also to define zones for which ET, recharge, and other water-budget information would be output by the model. The model was calibrated and tested using streamflow data from 10 streamflow-gaging stations; additionally, simulated ET was compared with measured ET from a meteorological station west of the study area. The model calibration is considered very good; streamflow volumes were calibrated to within 10 percent of measured streamflow volumes. During 2000-2007, the estimated annual mean rainfall for the water-budget zones ranged from 33.7 to 38.5 inches per year; the estimated annual mean rainfall for the entire watershed was 34.3 inches. Using the HSPF model it was estimated that for 2000-2007, less than 10 percent of the annual mean rainfall on the study watershed exited the watershed as streamflow, whereas about 82 percent, or an average of 28.2 inches per year, exited the watershed as ET. Estimated annual mean groundwater recharge for the entire study area was 3.0 inches, or about 9 percent of annual mean rainfall. Estimated annual mean recharge was largest in water-budget zone 3, the zone where the Carrizo Sand outcrops. In water-budget zone 3, the estimated annual mean recharge was 5.1 inches or about 15 percent of annual mean rainfall. Estimated annual mean recharge was smallest in water-budget zone 6, about 1.1 inches or about 3 percent of annual mean rainfall. The Cibolo Creek subwatershed and the subwatershed of the San Antonio River upstream from Cibolo Creek had the largest and smallest basin yields, about 4.8 inches and 1.2 inches, respectively. Estimated annual ET and annual recharge generally increased with increasing annual rainfall. Also, ET was larger in zones 8 and 9, the most downstream zones in the watershed. Model limitations include possible errors related to model conceptualization and parameter variability, lack of data to quantify certain model inputs, and measurement errors. Uncertainty regarding the degree to which available rainfall data represent actual rainfall is potentially the most serious source of measurement error.

Texas↗
USGS2019

Development of regression equations for the estimation of flood flows at ungaged streams in Pennsylvania

Regression equations, which may be used to estimate flood flows at select annual exceedance probabilities, were developed for ungaged streams in Pennsylvania. The equations were developed using annual peak flow data through water year 2015 and basin characteristics for 285 streamflow gaging stations across Pennsylvania and surrounding states. The streamgages included active and discontinued continuous-record stations, as well as crest-stage partial-record stations, and required a minimum of 10 years of annual peak streamflow data for inclusion in the study. Explanatory variables significant at the 95-percent confidence level for one or more regression equations included the following basin characteristics: drainage area, maximum basin elevation, mean basin slope, percent storage, and the percentage of carbonate bedrock within a basin. The State was divided into five regions, and regional regression equations were developed to estimate flood flows associated with the 50-, 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent annual exceedance probabilities (which correspond to the 2-, 5-, 10-, 25-, 50-, 100-, 200-, and 500-year recurrence intervals, respectively). Although the regression equations can be used to estimate the magnitude of flood flows for most streams in the State, they are not valid for streams with drainage areas generally greater than 1,500 square miles or with substantial regulation, diversion, or mining activity within the basin. The regional regression equations will be incorporated into the U.S. Geological Survey StreamStats application ( https://water.usgs.gov/osw/streamstats/ ). Additionally, annual peak flow data for 356 streamgages initially considered for inclusion in the analysis for development of updated flood-flow regression equations were analyzed for the existence of trends; estimates of flood-flow magnitude and frequency were also computed for these streamgages. Estimates of flood-flow magnitude and frequency for streamgages substantially affected by upstream regulation are also presented.

Pennsylvania↗
USGS2022

Suspended-sediment transport and water management, Jemez Canyon Dam, New Mexico, 1948–2018

Construction and operation of dams provide sources of clean drinking water, support large-scale irrigation, generate hydroelectricity, control floods, and improve river navigation. Yet these benefits are not without cost. Dams affect the natural flow regime, downstream sediment fluxes, and riverine and riparian ecosystems. The Jemez Canyon Dam in New Mexico was constructed in 1953 by the U.S. Army Corps of Engineers with authorizations for flood control and sediment retention. Water managers of the dam use various operational techniques to restore peak streamflow, improve sediment management, and restore altered ecosystem processes, while maintaining the authorized purposes of the dam. This study focuses on four distinct reservoir management operation periods implemented at the Jemez Canyon Dam: (1) predam (pre-1953), (2) a seasonal 24-hour hold pool (1953–79), (3) a permanent pool (1979–2001), and (4) dry reservoir (2001–18). Results of this study indicate successful flood control and reduction in peak instantaneous streamflow events following construction of the dam, specifically documented in 1958 and 2013. During the second water management operation period, moderate sediment retention (also defined as trap efficiency, which is the percentage of incoming sediments trapped within a reservoir during a given time) occurred (between 41.0 and 67.0 percent of sediments were retained). During the third period (1979–2001), between 61.2 and 99.8 percent of sediments were retained. During the fourth period (2001–18), at least 1,909 acre-feet of accumulated sediment were remobilized. The estimated dam trap efficiency during the fourth water management operation period was −37.2 percent, indicating that more sediments were being removed from the Jemez Canyon Reservoir than were being deposited. These remobilized sediments supplemented the natural sediment delivery in the Jemez River to the middle Rio Grande. The current (2022) dry reservoir operation allows sediment delivery during periods when flooding is not a concern while still providing flood control when needed. Suspended-sediment particle size data indicate potential coarsening of suspended sediments during the fourth water management operation period, likely resulting from erosion of coarse bed sediments deposited in the reservoir. Suspended-sediment particle size data during the first and fourth water management operation periods indicate that finer sediment mobilized during monsoon season than during snowmelt. Also, suspended-sediment concentrations during the predam and post-hold pool periods indicate concentrations were higher during monsoon season than during snowmelt. Seasonal variations in suspended-sediment concentration and particle size may help dam managers make operational decisions by increasing the understanding of particle size, concentration, and variation of suspended sediment during a given year. The seasonality of suspended-sediment transport can also vary, depending not only on concentration and particle size, but on precipitation. The maximum annual suspended-sediment loads occurred during all three seasonal categories analyzed in this study: snowmelt, monsoon, and the remainder of the year. This indicates that, in addition to sediment particle size and concentration, understanding the variability of transport mechanisms of suspended-sediment load can also guide optimal water management operations at a dam.

New Mexico↗
USGS1987

Ground-water resources of the Laura area, Majuro Atoll, Marshall Islands

The water system that supplies the heavily populated Dalap-Uliga-Darrit (DUD) area of Majuro atoll, Marshall Island, relies almost entirely upon airstrip catchment of rain water. Droughts cause severe water supply problems and water rationing is required, even during periods of normal rainfall. The Laura area contains a substantial lens of fresh groundwater that could be developed for export to the DUD area 30 mi to the east. Study of the groundwater resource at Laura involved a survey of existing wells, installation of monitoring wells and test holes, compilation of continuous records of rainfall and water level fluctuations, and collection of water quality data. Test hole data permitted the definition of three geohydrologic units which correlate well with similar units in Bikini and Enewetak atolls. The units consist of two layers of unconsolidated reef and lagoon sediments resting on a dense, highly permeable limestone. The potable water zone, or freshwater nucleus, of the lens is contained mostly within the unconsolidated layers, which are much less permeable than the basal limestone. Recharge to the Laura freshwater lens is estimated to be 1.8 mil gal/day, based on an average annual rainfall of 140 in. Sustainable yield is estimated to be about 400,000 gal/day. Shallow skimming wells or infiltration galleries similar to those used on Kwajalein atoll would be appropriate to develop the freshwater lens. The impact of development on the lens can be determined by monitoring the salinity in developed water and in a network of monitor wells.

Laura area, Majuro Atoll↗
USGS1997

Changes in bottom-surface elevations in three reservoirs on the lower Susquehanna River, Pennsylvania and Maryland, following the January 1996 flood — Implications for nutrient and sediment loads to Chesapeake Bay

The Susquehanna River drains about 27,510 square miles in New York, Pennsylvania, and Maryland, contributes nearly 50 percent of the freshwater discharge to the Chesapeake Bay, and contributes nearly 66 percent of the annual nitrogen load, 40 percent of the phosphorus load, and 25 percent of the suspended-sediment load from non-tidal parts of the Bay during a year of average streamflow. A reservoir system formed by three hydroelectric dams on the lower Susquehanna River is currently trapping a major part of the phosphorus and suspended-sediment loads from the basin and, to a lesser extent, the nitrogen loads. In the summer of 1996, the U. S. Geological Survey collected bathymetric data along 64 cross sections and 40 bottom-sediment samples along 14 selected cross sections in the lower Susquehanna River reservoir system to determine the remaining sediment-storage capacity, refine the current estimate of when the system may reach sediment-storage capacity, document changes in the reservoir system after the January 1996 flood, and determine the remaining nutrient mass in Conowingo Reservoir. Results from the 1996 survey indicate an estimated total of 14,800,000 tons of sediment were scoured from the reservoir system from 1993 (date of previous bathymetric survey) through 1996. This includes the net sediment change of 4,700,000 tons based on volume change in the reservoir system computed from the 1993 and 1996 surveys, the 6,900,000 tons of sediment deposited from 1993 through 1996, and the 3,200,000 tons of sediment transported into the reservoir system during the January 1996 flood. The January 1996 flood, which exceeded a 100-year recurrence interval, scoured about the same amount of sediment that normally would be deposited in the reservoir system during a 4- to 6-year period. Concentrations of total nitrogen in bottom sediments in the Conowingo Reservoir ranged from 1,500 to 6,900 mg/kg (milligrams per kilogram); 75 percent of the concentrations were between 3,000 and 5,000 mg/kg. About 96 percent of the concentrations of total nitrogen consisted of organic nitrogen. Concentrations of total phosphorus in bottom sediments ranged from 286 to 1,390 mg/kg. About 84 percent of the concentrations of total phosphorus were comprised of inorganic phosphorus. The ratio of concentrations of plant-available phosphorus to concentrations of total phosphorus ranged from 0.6 to 3.5 percent; ratios generally decreased in a downstream direction. About 29,000 acre-feet, or 42,000,000 tons, of sediment can be deposited before Conowingo Reservoir reaches sediment-storage capacity. Assuming the average annual sediment-deposition rate remains unchanged and no scour occurs due to floods, the reservoir system could reach sediment-storage capacity in about 17 years. The reservoir system currently is trapping about 2 percent of the nitrogen, 45 percent of the phosphorus, and 70 percent of the suspended sediment transported by the river to the upper Chesapeake Bay. Once the reservoir reaches sediment-storage capacity, an estimated 250-percent increase in the current annual loads of suspended sediment, a 2-percent increase in the current annual loads of total nitrogen, and a 70-percent increase in the current annual loads of total phosphorus from the Susquehanna River to Chesapeake Bay can be expected. If the goal of a 40-percent reduction in controllable phosphorus load from the Susquehanna River Basin is met before the reservoirs reach sediment-storage capacity, the 40-percent reduction goal will probably be exceeded when the reservoir system reaches sediment-storage capacity.

Maryland, Pennsylvania↗
USGS1999

Influence of land use and open-water wetlands on water quality in the Lake Wallenpaupack basin, northeastern Pennsylvania

The recreational value of Lake Wallenpaupack, along with its proximity to the New York and New Jersey metropolitan areas, has resulted in residential development in parts of the watershed. Some of these developments encroach on existing ponds, lakes, and wetlands and result in the conversion of forest land to residential areas. Sediment and nutrients in runoff from these residential areas, and inputs from agricultural areas, sewage treatment plants, and atmospheric deposition, have had a significant effect on water quality in Lake Wallenpaupack. Water-quality data collected in the Lake Wallenpaupack watershed from 1991 through 1994 indicate the influence of land use on water resources. Water samples collected from a forested undeveloped basin contained lower concentrations of suspended sediment, nitrogen, and total phosphorus than samples collected from the basins of Ariel Creek and Purdy Creek that drain areas having mixed land use with residential developments. Sediment yields were three to four times higher in the developed basins of Purdy and Ariel Creeks compared to the forested undeveloped basin. Annual yields for total nitrogen for Ariel Creek and Purdy Creek were between three to five times greater than yields from the forested basin. For the 1993 water year, the annual yield for dissolved nitrate plus nitrite (as nitrogen) from Ariel Creek Basin was 1,410 pounds per square mile, or about 60 times greater than the 24 pounds per square mile from the undeveloped basin. The total-phosphorus yield from the Ariel Creek Basin was 216 pounds per square mile for the 1994 water year. This was about three times greater than the 74 pounds per square mile from the forested basin. The total-phosphorus yield for the Purdy Creek Basin was 188 pounds per square mile for the 1994 water year, or 2.5 times greater than the yield from the undeveloped forested basin. Only slight differences were observed in dissolved orthophosphate phosphorus loadings between the basins. All three basins displayed seasonal differences in water quality. Most of the annual yield occurred during early spring as a result of snowmelt runoff. Data collected from the Stevens Creek sites showed that an open-water wetland was very effective in removing sediment and total phosphorus but was not as effective in removing dissolved orthophosphate phosphorus and nitrogen. The wetland removed more than 96 percent of the sediment.

Water-Resources Investigations Report↗
USGS1964

Sedimentation in three small forested drainage basins in the Alsea River basin, Oregon

A multidiscipline investigation to determine the effects of logging on the ecology of three small forested tributary basins is a part of an overall study of the Alsea River basin in the Coast Range of Oregon. The investigation of these small basins will be to (1) establish pre-logging conditions, (2) determine the effects of different logging methods, and (3) study the rate of recovery after the timber harvest. This report presents results of sedimentation in the basins, Deer and Flynn Creeks and Needle Branch, for the first 2 years of study (1959 and 1960 water years). Rainfall, runoff, and sediment discharge are seasonal for the Coast Range of western Oregon. About 95 percent of the rainfall and runoff occurs during the period October to May, but nearly 100 percent of the suspended-sediment discharge occurs during the same period. For Deer Creek, in the 1960 water year, 23 percent of the annual suspended-sediment discharge occurred on 1 day, 58 percent during the 10 days of greatest discharge, and 78 percent during the 38 days of greatest discharge. Rainfall is practically equal for all three of the basins. The runoff of the Deer and Flynn Creek basins is about equal, but that of the Needle Branch basin averaged 8 percent less. Sediment yield varies considerably for the three basins. The suspended-sediment yield of the Deer Creek basin is almost twice that of the Needle Branch basin and almost 1? times that of the Flynn Creek basin. Water temperature of the three streams varied only 22?F during the 2 water years. The greatest variation between streams was 3?F in the minimums. Water temperature effect can be neglected in comparing the sediment yields of the basins. The aquifers of the basins have low storage capacities as illustrated by the very low, late summer flow. A study of a midwinter freshet period for the Deer Creek basin showed that virtually all the rainfall left the basin as runoff within 4 days; the period of significant sediment transport was thus very short.

Circular↗
USGS2016

Evaluating external nutrient and suspended-sediment loads to Upper Klamath Lake, Oregon, using surrogate regressions with real-time turbidity and acoustic backscatter data

Executive Summary Suspended-sediment and total phosphorus loads were computed for two sites in the Upper Klamath Basin on the Wood and Williamson Rivers, the two main tributaries to Upper Klamath Lake. High temporal resolution turbidity and acoustic backscatter data were used to develop surrogate regression models to compute instantaneous concentrations and loads on these rivers. Regression models for the Williamson River site showed strong correlations of turbidity with total phosphorus and suspended-sediment concentrations (adjusted coefficients of determination [Adj R 2 ]=0.73 and 0.95, respectively). Regression models for the Wood River site had relatively poor, although statistically significant, relations of turbidity with total phosphorus, and turbidity and acoustic backscatter with suspended sediment concentration, with high prediction uncertainty. Total phosphorus loads for the partial 2014 water year (excluding October and November 2013) were 39 and 28 metric tons for the Williamson and Wood Rivers, respectively. These values are within the low range of phosphorus loads computed for these rivers from prior studies using water-quality data collected by the Klamath Tribes. The 2014 partial year total phosphorus loads on the Williamson and Wood Rivers are assumed to be biased low because of the absence of data from the first 2 months of water year 2014, and the drought conditions that were prevalent during that water year. Therefore, total phosphorus and suspended-sediment loads in this report should be considered as representative of a low-water year for the two study sites. Comparing loads from the Williamson and Wood River monitoring sites for November 2013–September 2014 shows that the Williamson and Sprague Rivers combined, as measured at the Williamson River site, contributed substantially more suspended sediment to Upper Klamath Lake than the Wood River, with 4,360 and 1,450 metric tons measured, respectively. Surrogate techniques have proven useful at the two study sites, particularly in using turbidity to compute suspended-sediment concentrations in the Williamson River. This proof-of-concept effort for computing total phosphorus concentrations using turbidity at the Williamson and Wood River sites also has shown that with additional samples over a wide range of flow regimes, high-temporal-resolution total phosphorus loads can be estimated on a daily, monthly, and annual basis, along with uncertainties for total phosphorus and suspended-sediment concentrations computed using regression models. Sediment-corrected backscatter at the Wood River has potential for estimating suspended-sediment loads from the Wood River Valley as well, with additional analysis of the variable streamflow measured at that site. Suspended-sediment and total phosphorus loads with a high level of temporal resolution will be useful to water managers, restoration practitioners, and scientists in the Upper Klamath Basin working toward the common goal of decreasing nutrient and sediment loads in Upper Klamath Lake.

Oregon↗
USGS2004

Geohydrology of the French Creek Basin and simulated effects of drought and ground-water withdrawals, Chester County, Pennsylvania

This report describes the results of a study by the U.S. Geological Survey, in cooperation with the Delaware River Basin Commission, to develop a regional ground-water-flow model of the French Creek Basin in Chester County, Pa. The model was used to assist water-resource managers by illustrating the interconnection between ground-water and surface-water systems. The 70.7-square mile French Creek Basin is in the Piedmont Physiographic Province and is underlain by crystalline and sedimentary fractured-rock aquifers. Annual water budgets were calculated for 1969-2001 for the French Creek Basin upstream of streamflow-measurement station French Creek near Phoenixville (01472157). Average annual precipitation was 46.28 in. (inches), average annual streamflow was 20.29 in., average annual base flow determined by hydrograph separation was 12.42 in., and estimated average annual ET (evapotranspiration) was 26.10 in. Estimated average annual recharge was 14.32 in. and is equal to 31 percent of the average annual precipitation. Base flow made up an average of 61 percent of streamflow. Ground-water flow in the French Creek Basin was simulated using the finite-difference MODFLOW-96 computer program. The model structure is based on a simplified two-dimensional conceptualization of the ground-water-flow system. The modeled area was extended outside the French Creek Basin to natural hydrologic boundaries; the modeled area includes 40 square miles of adjacent areas outside the basin. The hydraulic conductivity for each geologic unit was calculated from reported specific-capacity data determined from aquifer tests and was adjusted during model calibration. The model was calibrated for above-average conditions by simulating base-flow and water-level measurements made on May 1, 2001, using a recharge rate of 20 in/yr (inches per year). The model was calibrated for below-average conditions by simulating base-flow and water-level measurements made on September 11 and 17, 2001, using a recharge rate of 6.2 in/yr. Average conditions were simulated by adjusting the recharge rate until simulated streamflow at streamflow-measurement station 01472157 matched the long-term (1968-2001) average base flow of 54.1 cubic feet per second. The recharge rate used for average conditions was 15.7 in/yr. The effect of drought in the French Creek Basin was simulated using a drought year recharge rate of 8 in/yr for 3 months. After 3 months of drought, the simulated streamflow of French Creek at streamflow-measurement station 01472157 decreased 34 percent. The simulations show that after 6 months of average recharge (15.7 in/yr) following drought, streamflow and water levels recovered almost to pre-drought conditions. The effect of increased ground-water withdrawals on stream base flow in the South Branch French Creek Subbasin was simulated under average and drought conditions with pumping rates equal to 50, 75, and 100 percent of the Delaware River Basin Commission Ground Water Protected Area (GWPA) withdrawal limit (1,393 million gallons per year) with all pumped water removed from the basin. For average recharge conditions, the simulated streamflow of South Branch French Creek at the mouth decreased 18, 28, and 37 percent at a withdrawal rate equal to 50, 75, and 100 percent of the GWPA limit, respectively. After 3 months of drought recharge conditions, the simulated streamflow of South Branch French Creek at the mouth decreased 27, 40, and 52 percent at a withdrawal rate equal to 50, 75, and 100 percent of the GWPA limit, respectively. The effect of well location on base flow, water levels, and the sources of water to the well was simulated by locating a hypothetical well pumping 200 gallons per minute in different places in the Beaver Run Subbasin with all pumped water removed from the basin. The smallest reduction in the base flow of Beaver Run was from a well on the drainage divide between the French Creek Basin and the Marsh Creek Basin to the south; the simulated base flow of Beaver Run at the mouth was reduced 1 percent. The greatest reduction in the base flow of Beaver Creek was from a well close to Beaver Run; the simulated base flow of Beaver Run at the mouth was reduced 8 percent. The simulations showed that (1) if the contributing area of a well is in a basin, pumping will affect stream base flow and water levels in that basin whether the well is inside or outside that basin; (2) wells in different areas of a basin away from a divide produce a similar reduction in base flow; (3) a well within a basin will derive more water from diverted base flow and less water from storage than a well on or near a basin divide; and (4) the reduction in base flow at the mouth of the stream is the same for a well in the headwaters and a well downstream near the confluence. Model simulations illustrate some of the typical analyses and results that can be produced. The model was calibrated using annual values for recharge and ground-water ET and then was run using the annual values in a seasonally independent transient mode to show changes with time. The timing and relative magnitude of some of the changes simulated with the model when viewed in terms of a normal climatic year may be subject to considerable uncertainty because of the variability in seasonal recharge and ground-water ET rates. Transient model simulations for short-term periods are indicative of possible hydrologic system response and are considered an approximation.

Pennsyvlania↗