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At least 1,117 records · Page 62Linked to original sources
USGS1988

Streamflow characteristics of the Green, Bear, and Snake River basins, Wyoming, through 1984

A summary of streamflow characteristics as of 1984 is presented for the Green, Bear, and Snake River Basins in Wyoming and adjacent areas, based on data from 101 streamflow-gaging stations. Streamflow characteristics include mean monthly and mean annual streamflow, duration of daily mean flow, and magnitude and probability of instantaneous peak flow, annual high flow, and annual low flow. Recurrence intervals of 2, 5, 10 , 25, 50 and 100 yr are utilized for the peak-flow, high-flow and low-flow characteristics. Low-flow and high-flow characteristics are also listed for standard periods of consecutive days. A station description, tables of streamflow characteristics, and graphs of mean monthly streamflow and duration of daily mean streamflow are presented for each station. Streamflow characteristics before and after dam construction are presented for five stations. (USGS)

Water-Resources Investigations Report↗
USGS1995

Water-quality characteristics of streams in the Treyburn Development area of Falls Lake watershed, North Carolina, 1988-93

Treyburn is a 5,400 acre planned, mixed-use community located in the Falls Lake watershed in the upper Neuse River Basin of North Carolina. From February 1988 through 1993, hydrologic-data were collected at 17 study sites in or near the Treyburn development to compare the effects of varying types of land-use development on the water-quality of streams flowing in or near the development. The collected hydrologic data included measurements of streamflow and concentrations of major dissolved constituents, nutrients, minor elements, and organic compounds. Streamflow in the study basin was approximately 40 percent lower in 1992 and 40 percent higher in 1993 than the long-term annual mean of the long-term discharge records at Flat River in Bahama. Calcium and bicarbonate were the predominant cation and anion at all study sites except one. Mean total nitrogen and phosphorus concentrations at sites in the Treyburn development ranged from 0.5 to 0.8 and 0.03 to 0.10 milligrams per liter, respectively. Total aluminum, iron, and manganese were the metals most frequently detected in the 200 organic compunds analyzed. Dichloro- difluoromethane and methylene chloride were detected most often.

North Carolina↗
USGS1996

Evaluation of the streamflow-gaging network of Alaska in providing regional streamflow information

In 1906, the U.S. Geological Survey (USGS) began operating a network of streamflow-gaging stations in Alaska. The primary purpose of the streamflow- gaging network has been to provide peak flow, average flow, and low-flow characteristics to a variety of users. In 1993, the USGS began a study to evaluate the current network of 78 stations. The objectives of this study were to determine the adequacy of the existing network in predicting selected regional flow characteristics and to determine if providing additional streamflow-gaging stations could improve the network's ability to predict these characteristics. Alaska was divided into six distinct hydrologic regions: Arctic, Northwest, Southcentral, Southeast, Southwest, and Yukon. For each region, historical and current streamflow data were compiled. In Arctic, Northwest, and Southwest Alaska, insufficient data were available to develop regional regression equations. In these areas, proposed locations of streamflow-gaging stations were selected by using clustering techniques to define similar areas within a region and by spatial visual analysis using the precipitation, physiographic, and hydrologic unit maps of Alaska. Sufficient data existed in Southcentral and Southeast Alaska to use generalized least squares (GLS) procedures to develop regional regression equations to estimate the 50-year peak flow, annual average flow, and a low-flow statistic. GLS procedures were also used for Yukon Alaska but the results should be used with caution because the data do not have an adequate spatial distribution. Network analysis procedures were used for the Southcentral, Southeast, and Yukon regions. Network analysis indicates the reduction in the sampling error of the regional regression equation that can be obtained given different scenarios. For Alaska, a 10-year planning period was used. One scenario showed the results of continuing the current network with no additional gaging stations and another scenario showed the results of adding gaging stations to the network. With the exception of the annual average discharge equation for Southeast Alaska, by adding gaging stations in all three regions, the sampling error was reduced to a greater extent than by not adding gaging stations. The proposed streamflow-gaging network for Alaska consists of 308 gaging stations, of which 32 are designated as index stations. If the proposed network can not be implemented in its entirety, then a lesser cost alternative would be to establish the index stations and to implement the network for a particular region.

Water-Resources Investigations Report↗
USGS1971

Geology and water resources of the Spanish Valley area, Grand and San Juan Counties, Utah

This water-resources investigation was initiated in order to provide an estimate of the average annual water yield of the Mill Creek-Pack Creek drainage basin, the parts of that total yield available as surface water and ground water, the amount of ground water that might be recovered for beneficial use, and the effect of this use on the usable ground-water storage within the valley fill in Spanish and Moab Valleys. Detailed information has been sought which is basic to the establishment of sound policies for the development and management of water resources. The investigation was carried out as part of water-resources investigations in Utah with the Utah Division of Water Rights, Department of Natural Resources. Fieldwork was done during the period July 1967-November 1969.

Utah↗
USGS2018

External quality assurance project report for the National Atmospheric Deposition Program’s National Trends Network and Mercury Deposition Network, 2015–16

The U.S. Geological Survey Precipitation Chemistry Quality Assurance project operated five distinct programs to provide external quality assurance monitoring for the National Atmospheric Deposition Program’s (NADP) National Trends Network and Mercury Deposition Network during 2015–16. The National Trends Network programs include (1) a field audit program to evaluate sample contamination and stability, (2) an interlaboratory comparison program to evaluate analytical laboratory performance, and (3) a colocated sampler program to evaluate bias and variability attributed to automated precipitation samplers. The Mercury Deposition Network programs include the (4) system blank program and (5) an interlaboratory comparison program. The results indicate that NADP data continue to be of sufficient quality for the analysis of spatial distributions and time trends for chemical constituents in wet deposition. The field audit program results indicate increased sample contamination for calcium, magnesium, and potassium relative to 2010 levels, and slight fluctuation in sodium contamination. Nitrate contamination levels dropped slightly during 2014–16, and chloride contamination leveled off between 2007 and 2016. Sulfate contamination is similar to the 2000 level. Hydrogen ion contamination has steadily decreased since 2012. Losses of ammonium and nitrate resulting from potential sample instability were negligible. The NADP Central Analytical Laboratory produced interlaboratory comparison results with low bias and variability compared to other domestic and international laboratories that support atmospheric deposition monitoring. Significant absolute bias above the magnitudes of the detection limits was observed for nitrate and sulfate concentrations, but no analyte determinations exceeded the detection limits for blanks. Colocated sampler program results from dissimilar colocated collectors indicate that the retrofit of the National Trends Network with N-CON Systems Company, Inc. precipitation collectors could cause substantial shifts in NADP annual deposition (concentration multiplied by depth) values. Median weekly relative percent differences for analyte concentrations ranged from -4 to +76 percent for cations, from 5 to 6 percent for ammonium, from +14 to +25 percent for anions, and from -21 to +8 percent for hydrogen ion contamination. By comparison, weekly absolute concentration differences for paired identical N-CON Systems Company, Inc., collectors ranged from 4–22 percent for cations; 2–9 percent for anions; 4–5 percent for ammonium; and 13–14 percent for hydrogen ion contamination. The N-CON Systems Company, Inc. collector caught more precipitation than the Aerochem Metrics Model 301 collector (ACM) at the WA99/99WA sites, but it typically caught slightly less precipitation than the ACM at ND11/11ND, sites which receive more wind and snow than WA99/99WA. Paired, identical OTT Pluvio-2 and ETI Noah IV precipitation gages were operated at the same sites. Median absolute percent differences for daily measured precipitation depths ranged from 0 to 7 percent. Annual absolute differences ranged from 0.08 percent (ETI Noah IV precipitation gages) to 11 percent (OTT Pluvio-2 precipitation gages). The Mercury Deposition Network programs include the system blank program and an interlaboratory comparison program. System blank results indicate that maximum total mercury contamination concentrations in samples were less than the third percentile of all Mercury Deposition Network sample concentrations (1.098 nanograms per liter; ng/L). The Mercury Analytical Laboratory produced chemical concentration results with low bias and variability compared with other domestic and international laboratories that support atmospheric-deposition monitoring. The laboratory’s performance results indicate a +1-ng/L shift in bias between 2015 (-0.4 ng/L) and 2016 (+0.5 ng/L).

Scientific Investigations Report↗
USGS2014

Water and nutrient budgets for Vancouver Lake, Vancouver, Washington, October 2010-October 2012

Vancouver Lake, a large shallow lake in Clark County, near Vancouver, Washington, has been undergoing water-quality problems for decades. Recently, the biggest concern for the lake are the almost annual harmful cyanobacteria blooms that cause the lake to close for recreation for several weeks each summer. Despite decades of interest in improving the water quality of the lake, fundamental information on the timing and amount of water and nutrients entering and exiting the lake is lacking. In 2010, the U.S. Geological Survey conducted a 2-year field study to quantify water flows and nutrient loads in order to develop water and nutrient budgets for the lake. This report presents monthly and annual water and nutrient budgets from October 2010–October 2012 to identify major sources and sinks of nutrients. Lake River, a tidally influenced tributary to the lake, flows into and out of the lake almost daily and composed the greatest proportion of both the water and nutrient budgets for the lake, often at orders of magnitude greater than any other source. From the water budget, we identified precipitation, evaporation and groundwater inflow as minor components of the lake hydrologic cycle, each contributing 1 percent or less to the total water budget. Nutrient budgets were compiled monthly and annually for total nitrogen, total phosphorus, and orthophosphate; and, nitrogen loads were generally an order of magnitude greater than phosphorus loads across all sources. For total nitrogen, flow from Lake River at Felida, Washington, made up 88 percent of all inputs into the lake. For total phosphorus and orthophosphate, Lake River at Felida flowing into the lake was 91 and 76 percent of total inputs, respectively. Nutrient loads from precipitation and groundwater inflow were 1 percent or less of the total budgets. Nutrient inputs from Burnt Bridge Creek and Flushing Channel composed 12 percent of the total nitrogen budget, 8 percent of the total phosphorus budget, and 21 percent of the orthophosphate budget. We identified several data gaps and areas for future research, which include the need for better understanding nutrient inputs to the lake from sediment resuspension and better quantification of indirect nutrient inputs to the lake from Salmon Creek.

Washington↗
USGS1995

Using chloride and chlorine-36 as soil-water tracers to estimate deep percolation at selected locations on the U.S. Department of Energy Hanford site, Washington

Long-term average deep-percolation rates of water from precipitation on the U.S. Department of Energy Hanford Site in semiarid south-central Washington, as estimated by a chloride mass-balance method, range from 0.008 to 0.30 mm/yr (millimeters per year) at nine locations covered by a variety of fine-grain soils and vegetated with sagebrush and other deep-rooted plants plus sparse shallow-rooted grasses. Deep-percolation rates estimated using a chlorine-36 bomb-pulse method at three of the nine locations range from 2.1 to 3.4 mm/yr. Because the mass-balance method may underestimate percolation rates and the bomb-pulse method probably overestimates percolation rates, estimates by the two methods probably bracket actual rates. These estimates, as well as estimates by previous investigators who used different methods, are a small fraction of mean annual precipitation, which ranges from about 160 to 210 mm/yr at the different test locations. Estimates by the mass-balance method at four locations in an area that is vegetated only with sparse shallow-rooted grasses range from 0.39 to 2.0 mm/yr. Chlorine-36 data at one location in this area were sufficient only to determine that the upper limit of deep percolation is more than 5.1 mm/yr. Although estimates for locations in this area are larger than the estimates for locations with deep-rooted plants, they are at the lower end of the range of estimates for this area made by previous investigators.

Washington↗
USGS2009

Potentiometric Surface of the Upper Floridan Aquifer, West-Central Florida, May 2009

The Floridan aquifer system consists of the Upper and Lower Floridan aquifers separated by the middle confining unit. The middle confining unit and the Lower Floridan aquifer in west-central Florida generally contain highly mineralized water. The water-bearing units containing fresh water are herein referred to as the Upper Floridan aquifer. The Upper Floridan aquifer is the principal source of water in the Southwest Florida Water Management District and is used for major public supply, domestic use, irrigation, and brackish water desalination in coastal communities (Southwest Florida Water Management District, 2000). This map report shows the potentiometric surface of the Upper Floridan aquifer measured in May 2009. The potentiometric surface is an imaginary surface connecting points of equal altitude to which water will rise in tightly-cased wells that tap a confined aquifer system (Lohman, 1979). This map represents water-level conditions near the end of the dry season, when ground-water levels usually are at an annual low and withdrawals for agricultural use typically are high. The cumulative average rainfall of 48.53 inches for west-central Florida (from June 2008 through May 2009) was 4.12 inches below the historical cumulative average of 52.65 inches (Southwest Florida Water Management District, 2009). Historical cumulative averages are calculated from regional rainfall summary reports (1915 to most recent complete calendar year) and are updated monthly by the Southwest Florida Water Management District. This report, prepared by the U.S. Geological Survey in cooperation with the Southwest Florida Water Management District, is part of a semi-annual series of Upper Floridan aquifer potentiometric-surface map reports for west-central Florida. Potentiometric-surface maps have been prepared for January 1964, May 1969, May 1971, May 1973, May 1974, and for each May and September since 1975. Water-level data are collected in May and September each year to show the approximate annual low and high water-level conditions, respectively. Most of the water-level data for this map were collected by the U.S. Geological Survey during the period May 18-22, 2009. Supplemental water-level data were collected by other agencies and companies. A corresponding potentiometric-surface map was prepared for areas east and north of the Southwest Florida Water Management District boundary by the U.S. Geological Survey office in Orlando, Florida (Kinnaman and Dixon, 2009). Most water-level measurements were made during a 5-day period; therefore, measurements do not represent a 'snapshot' of conditions at a specific time, nor do they necessarily coincide with the seasonal low water-level condition. The potentiometric contours are generalized to synoptically portray the head in a dynamic hydrologic system, taking due account of the variations in hydrogeologic conditions, such as differing depths of wells, nonsimultaneous measurements of water levels, variable effects of pumping, and changing climatic influence. The potentiometric contours may not conform exactly with the individual measurements of water levels.

Scientific Investigations Map↗
USGS2006

An evaluation and review of water-use estimates and flow data for the Lower Klamath and Tule Lake National Wildlife Refuges, Oregon and California

The Lower Klamath and Tule Lake National Wildlife Refuges, located in the upper Klamath Basin of Oregon and California, encompass approximately 46,700 and 39,100 acres, respectively. Demand for water in the semiarid upper Klamath Basin has increased in recent years, resulting in the need to better quantify water availability and use in the refuges. This report presents an evaluation of water-use estimates for both refuges derived on the basis of two approaches. One approach used evaporation and evapotranspiration estimates and the other used measured inflow and outflow data. The quality of the inflow and outflow data also was assessed. Annual water use in the refuges, using evapotranspiration estimates, was computed with the use of different rates for each of four land-use categories. Annual water-use rates for grain fields, seasonal wetlands, permanently flooded wetlands with emergent vegetation, and open-water bodies were 2.5, 2.9, 2.63, and 4.07 feet per year, respectively. Total water use was estimated as the sum of the products of each rate and the number of acres in its associated land-use category. Mean annual (2003-2005) water use for the Lower Klamath and Tule Lake refuges was approximately 124,000 and 95,900 acre-feet, respectively. To estimate water deliveries needed for each refuge, first, annual precipitation for 2003-2005 was subtracted from the annual water use for those years. Then, an adjusted total was obtained by adding 20 percent to the difference to account for salinity flushing. Resulting estimated mean annual adjusted needed water deliveries in 2003-2005 for the Lower Klamath and Tule Lake refuges were 107,000 and 82,800 acre-feet, respectively. Mean annual net inflow to the refuges for 2003-2005 was computed by subtracting estimated and measured surface-water outflows from inflows. Mean annual net inflow during the 3-year period for the Lower Klamath refuge, calculated for a subsection of the refuge, was approximately 73,700 acre-feet. The adjusted needed water delivery for this section of the refuge, calculated from evapotranspiration estimates, was approximately 77,600 acre-feet. For the Tule Lake refuge, mean annual net inflow during the 3-year period was approximately 76,100 acre-feet, which is comparable to the estimated annual needed water delivery for the refuge of 82,800 acre-feet. For 1962-2005, mean annual net inflow to the Lower Klamath refuge was approximately 49,800 acre-feet, about 23,900 acre-feet less than for 2003-2005. Although mean April-September net inflows for 1962-2005 and 2003-2005 have remained fairly constant, annual net inflow has increased for October-March, which accounts for the difference. Consistently higher autumn and winter flow deliveries since the mid-1980s reflect a significant change in refuge management. More sections of the refuge are currently managed as seasonal wetlands than were in the 1960s and 1970s. Flow records for the Ady Canal at State Line Road, Klamath Straits Drain at State Line Road, and D Pumping Plant were evaluated for their data quality. On the basis of USGS flow-record criteria, all three flow records were rated as 'poor.' By definition, 95 percent of the daily flows in a record having this rating could be in error by more than 15 percent.

Scientific Investigations Report↗
USGS2013

Evaluation of blood and muscle tissues for molecular detection and characterization of hematozoa infections in northern pintails ( Anas acuta ) wintering in California

Information on the molecular detection of hematozoa from different tissue types and multiple years would be useful to inform sample collection efforts and interpret results of meta-analyses or investigations spanning multiple seasons. In this study, we tested blood and muscle tissue collected from northern pintails ( Anas acuta ) during autumn and winter of different years to evaluate prevalence and genetic diversity of Leucocytozoon , Haemoproteus , and Plasmodium infections in this abundant waterfowl species of the Central Valley of California. We first compared results for paired blood and wing muscle samples to assess the utility of different tissue types for molecular investigations of haemosporidian parasites. Second, we explored inter-annual variability of hematozoa infection in Central Valley northern pintails and investigated possible effects of age, sex, and sub-region of sample collection on estimated parasite detection probability and prevalence. We found limited evidence for differences between tissue types in detection probability and prevalence of Leucocytozoon , Haemoproteus , and Plasmodium parasites, which supports the utility of both sample types for obtaining information on hematozoan infections. However, we detected 11 haemosporidian mtDNA cyt b haplotypes in blood samples vs. six in wing muscle tissue collected during the same sample year suggesting an advantage to using blood samples for investigations of genetic diversity. Estimated prevalence of Leucocytozoon parasites was greater during 2006–2007 as compared to 2011–2012 and four unique haemosporidian mtDNA cyt b haplotypes were detected in the former sample year but not in the latter. Seven of 15 mtDNA cyt b haplotypes detected in northern pintails had 100% identity with previously reported hematozoa lineages detected in waterfowl ( Haemoproteus and Leucocytozoon ) or other avian taxa ( Plasmodium ) providing support for lack of host specificity for some parasite lineages.

California↗
USGS2013

Tracking sedimentation from the historic A.D. 2011 Mississippi River flood in the deltaic wetlands of Louisiana, USA

Management and restoration of the Mississippi River deltaic plain (southern United States) and associated wetlands require a quantitative understanding of sediment delivery during large flood events, past and present. Here, we investigate the sedimentary fingerprint of the 2011 Mississippi River flood across the Louisiana coast (Atchafalaya Delta, Terrebonne, Barataria, and Mississippi River Delta basins) to assess spatial patterns of sedimentation and to identify key indicators of sediment provenance. The sediment deposited in wetlands during the 2011 flood was distinguished from earlier deposits based on biological characteristics, primarily absence of plant roots and increased presence of centric (planktonic) diatoms indicative of riverine origin. By comparison, the lithological (bulk density, organic matter content, and grain size) and chemical (stable carbon isotopes of bulk organic matter) properties of flood sediments were nearly identical to the underlying deposit. Flood sediment deposition was greatest in wetlands near the Atchafalaya and Mississippi Rivers and accounted for a substantial portion (37% to 85%) of the annual accretion measured at nearby monitoring stations. The amount of sediment delivered to those basins (1.1–1.6 g cm −2 ) was comparable to that reported previously for hurricane sedimentation along the Louisiana coast (0.8–2.1 g cm −2 ). Our findings not only provide insight into how large-scale river floods influence wetland sedimentation, they lay the groundwork for identifying previous flood events in the stratigraphic record.

Louisiana↗
USGS2008

A comparison of runoff quantity and quality from two small basins undergoing implementation of conventional- and low-impact-development (LID) strategies: Cross Plains, Wisconsin, water years 1999–2005

Environmental managers are often faced with the task of designing strategies to accommodate development while minimizing adverse environmental impacts. Low-impact development (LID) is one such strategy that attempts to mitigate environmental degradation commonly associated with impervious surfaces. The U.S. Geological Survey, in cooperation with the Wisconsin Department of Natural Resources, studied two residential basins in Cross Plains, Wis., during water years 1999–2005. A paired-basin study design was used to compare runoff quantity and quality from the two basins, one of which was developed in a conventional way and the other was developed with LID. The conventional-developed basin (herein called “conventional basin”) consisted of curb and gutter, 40-foot street widths, and a fully connected stormwater-conveyance system. The LID basin consisted of grassed swales, reduced impervious area (32-foot street widths), street inlets draining to grass swales, a detention pond, and an infiltration basin. Data collected in the LID basin represented predevelopment through near-complete build-out conditions. Smaller, more frequent precipitation events that produced stormwater discharge from the conventional basin were retained in the LID basin. Only six events with precipitation depths less than or equal to 0.4 inch produced measurable discharge from the LID basin. Of these six events, five occurred during winter months when underlying soils are commonly frozen, and one was likely a result of saturated soil from a preceding storm. In the conventional basin, the number of discharge events, using the same threshold of precipitation depth, was 180, with nearly one-half of those resulting from precipitation depths less than 0.2 inch. Precipitation events capable of producing appreciable discharge in the LID basin were typically those of high intensity or precipitation depth or those that occurred after soils were already saturated. Total annual discharge volume measured from the conventional basin ranged from 1.3 to 9.2 times that from the LID basin. Development of the LID basin did not appreciably alter the hydrologic response to precipitation characterized during predevelopment conditions. Ninety-five percent or more of precipitation in the LID basin was retained during each year of construction from predevelopment through near-complete build-out, surpassing the 90-percent benchmark established for new development by the Wisconsin Department of Natural Resources. The amount of precipitation retained in the conventional basin did not exceed 94 percent and fell below the 90-percent standard 2 of the 6 years monitored. Much of the runoff in the LID basin was retained by an infiltration basin, the largest control structure used to mitigate storm-runoff quantity and quality. The infiltration basin also was the last best-management practice (BMP) used to treat runoff before it left the LID basin as discharge. From May 25, 2002, to September 30, 2005, only 24 of 155 precipitation events exceeded the retention/ infiltrative capacity of the infiltration basin. The overall reduction in runoff volume from these few events was 51 percent. The effectiveness of the infiltration basin decreased as precipitation intensities exceeded 0.5 inch per hour. Annual loads were estimated to characterize the overall effectiveness of low-impact design practices for mitigating delivery of total solids, total suspended solids, and total phosphorus. Annual loads of these three constituents were greater in the LID basin than in the conventional basin in 2000 and 2004. Seventy percent or more of all constituent annual loads were associated with two discharge events in 2000, and a single discharge event produced 50 percent or more of constituent annual loads in 2004. Each of these discharge events was associated with considerable precipitation depths and (or) intensities, ranging from 4.89 to 6.21 inches and from 1.13 to 1.2 inches per hour, respectively. These same storms did not contribute as much of the annual load in the conventional basin. With large storms and saturated soils, the ability of low-impact design techniques to reduce runoff, and thus constituent loads, can be greatly diminished. For both the LID and conventional basins, the temperature of runoff was largely affected by ambient air temperatures. However, the temperature of discharge from the LID basin increased upon runoff cessation. This increase is likely due to solar heating of water that is temporarily stored in the detention pond and infiltration basin.

Wisconsin↗
USGS2009

Channel morphodynamics in four reaches of the Lower Missouri River, 2006-07

Channel morphodynamics in response to flow modifications from Gavins Point Dam are examined in four reaches of the Lower Missouri River. Measures include changes in channel morphology and indicators of sediment transport in four 6 kilometer long reaches located downstream from Gavins Point Dam, near Yankton, South Dakota, Kenslers Bend, Nebraska, Little Sioux, Iowa, and Miami, Missouri. Each of the four reaches was divided into 300 transects with a 20-meter spacing and surveyed during the summer in 2006 and 2007. A subset of 30 transects was randomly selected and surveyed 7-10 times in 2006-07 over a wide range of discharges including managed and natural flow events. Hydroacoustic mapping used a survey-grade echosounder and a Real Time Kinematic Global Positioning System to evaluate channel change. Acoustic Doppler current profiler measurements were used to evaluate bed-sediment velocity. Results indicate varying amounts of deposition, erosion, net change, and sediment transport in the four Lower Missouri River reaches. The Yankton reach was the most stable over monthly and annual time-frames. The Kenslers Bend and Little Sioux reaches exhibited substantial amounts of deposition and erosion, although net change was generally low in both reaches. Total, or gross geomorphic change was greatest in the Kenslers Bend reach. The Miami reach exhibited varying rates of deposition and erosion, and low net change. The Yankton, Kenslers Bend, and Miami reaches experienced net erosion during the time period that bracketed the managed May 2006 spring rise event from Gavins Point Dam.

Scientific Investigations Report↗
USGS2001

Hydrogeology of the Tully Lakes area in southern Onondaga and northern Cortland Counties, New York

Water levels in a series of kettlehole lakes and ponds known as the Tully Lakes respond to seasonal water-level changes in the surrounding aquifer but often differ from ground-water levels in the aquifer because the lakebed sediments are poorly permeable and inhibit the exchange of water. Three sets of ground-water-level measurements were made from the spring recharge period of 2000 through the fall of that year. Seasonal ground-water-level declines ranged from 1.5 to 8 feet. Average annual water-level fluctuations in the three western lakes ranged from 2.5 to 6 feet, whereas those in the two eastern lakes were only about 1.5 feet because these lakes have natural outlets. The ground-water divide between the St. Lawrence and Susquehanna River Basins did not coincide with the surface-water divide and the ground-water divide moved southerly in response to lower water levels in the aquifer during the summer and fall.

New York↗
USGS1995

Ground-water flow and water quality in the sand aquifer of Long Beach Peninsula, Washington

This report describes an investigation of ground-water flow and water quality in the sand aquifer of the Long Beach Peninsula. The peninsula is located in the southwestern corner of the State of Washington, is about 27 miles long, and has an average width of about 1.5 miles. It is surrounded by seawater, by the Pacific Ocean on the west and Willapa Bay on the east. Water supplies on the peninsula are derived mostly from a local water-table aquifer composed largely of sand. The recent growth of population on the peninsula and the projected future growth have created concerns about the quantity and quality of the ground-water resource. Some issues include declining ground-water levels from increased pumpage, and ground-water contamination from seawater intrusion, pesticides or fertilizers from cranberrygrowing areas, and septic-system effluent. The ground-water system of the Long Beach Peninsula consists of a sand aquifer with some lenses of silt and clay that may act as confining beds in local areas. Data are lacking or inconsistent to define a confining bed that extends throughout the peninsula. Hydraulic conductivity calculated from slug tests in 58 shallow wells ranged from 10 to 37 feet per day with a median of 22 feet per day. Average annual ground-water recharge by infiltration and percolation of precipitation is estimated to be about 58 inches or 111,000 acre-feet, which is 72 percent of the average annual precipitation of 80 inches. Average annual ground-water discharge is estimated to be about 30,200 acre-feet to the Pacific Ocean, 56,000 acre-feet to Willapa Bay, and 24,800 acre-feet to surface-water drainage channels. Ground-water movement is generally perpendicular to the spine of the peninsula. A ground-water divide occurs along a north-south line and ground water flows west or east from the divide toward the Pacific Ocean or Willapa Bay. There does not appear to have been any long-term decline of the water table of the sand aquifer from 1974-92. Ground-water levels measured at three east-west cross sections in 1974-75 were at about the same altitude as water levels measured in 1992. Relatively accurate individual regression relations were developed at 45 wells with ground-water altitude as a response variable and cumulative precipitation for 4 months as an explanatory variable. The average coefficient of determination for all individual relations was 0.77, with a range of 0.11 to 0.89. Some empirical frequency or probability relations for precipitation and ground-water levels were used to estimate how often the maximum water levels measured in this study would be expected to occur in the future. These water levels reflected the lower-than-average precipitation that occurred during the study. Assuming that the annual maximum precipitation for 4 consecutive months is random and independent, the historical record of precipitation is representative of the future distribution of precipitation, and the relation between precipitation and water levels is accurate and stationary; a probability analysis of the historical record indicates that in any one year in the future there is a probability of 70 percent that the maximum water levels measured in wells during the winter of 1991-92 would be equaled or exceeded. The shallow ground water had generally low dissolved-solids concentrations in July 1992, with a median concentration of 92 milligrams per liter (mg/L) and a range of 56 to 218 mg/L. Sodium was the dominant cation and bicarbonate was the dominant anion. The distribution of hardness of the water samples was 84 percent with soft water and 16 percent with moderately hard water. The water quality of the shallow ground water was generally good, with a few small to moderate problems. A natural problem is locally high concentrations of dissolved iron. About 30 percent of the water samples had dissolved-iron concentrations of greater than 0.3 mg/L, which is the secondary maximum contaminant level established by the U.S. Environmental Protection Agency. No appreciable amount of seawater has intruded into the sand aquifer. The samples of shallow ground water collected in July 1992 had a median chloride concentration of 15 mg/L and a maximum concentration of 52 mg/L. The heavy average annual precipitation of about 80 inches, large average annual ground-water recharge of about 58 inches or 111,000 acre-feet, and small ground-water withdrawal rate (about 780 acre-feet per year in 1992) combine to maintain a thick freshwater lens of ground water that prevents seawater intrusion throughout the year. Agricultural activities do not appear to have appreciably affected the quality of shallow ground water on the Long Beach Peninsula. The concentration of nitrate in ground water was not significantly higher near cranberry-growing areas, and no sample of ground water or surface water had concentrations of selected pesticides or associated compounds that were above the analytical detection limits. Of the seven ground-water samples in which bacteria were detected, only one sample appeared to be related to agriculture; that sample was from a well located in an area where cattle graze for part of the year. Septic systems probably caused an increase in the concentration of nitrate in shallow ground water in areas of higher population density. Concentrations of nitrate were significantly related to population density. However, the concentrations were not generally high; median concentrations of nitrate increased from less than 0.05 mg/L in areas of low population density to 0.74 mg/L in areas of high density. Septic systems did not cause regional bacterial contamination of the ground water. Bacteria were detected in seven ground-water samples; however, only two of those samples were from wells that are close to septic systems. A limited amount of historical water-quality data is available for the peninsula; therefore, it is difficult to assess long-term changes. From 1968-92, chloride concentrations and values of specific conductance appear to have remained stable. Likewise, it appears that nitrate concentrations did not change from 1987-92.

Washington↗
USGS2015

Water-budgets and recharge-area simulations for the Spring Creek and Nittany Creek Basins and parts of the Spruce Creek Basin, Centre and Huntingdon Counties, Pennsylvania, Water Years 2000–06

This report describes the results of a study by the U.S. Geological Survey in cooperation with ClearWater Conservancy and the Pennsylvania Department of Environmental Protection to develop a hydrologic model to simulate a water budget and identify areas of greater than average recharge for the Spring Creek Basin in central Pennsylvania. The model was developed to help policy makers, natural resource managers, and the public better understand and manage the water resources in the region. The Groundwater and Surface-water FLOW model (GSFLOW), which is an integration of the Precipitation-Runoff Modeling System (PRMS) and the Modular Groundwater Flow Model (MODFLOW-NWT), was used to simulate surface water and groundwater in the Spring Creek Basin for water years 2000–06. Because the groundwater and surface-water divides for the Spring Creek Basin do not coincide, the study area includes the Nittany Creek Basin and headwaters of the Spruce Creek Basin. The hydrologic model was developed by the use of a stepwise process: (1) develop and calibrate a PRMS model and steady-state MODFLOW-NWT model; (2) re-calibrate the steady-state MODFLOW-NWT model using potential recharge estimates simulated from the PRMS model, and (3) integrate the PRMS and MODFLOW-NWT models into GSFLOW. The individually calibrated PRMS and MODFLOW-NWT models were used as a starting point for the calibration of the fully coupled GSFLOW model. The GSFLOW model calibration was done by comparing observations and corresponding simulated values of streamflow from 11 streamgages and groundwater levels from 16 wells. The cumulative water budget and individual water budgets for water years 2000–06 were simulated by using GSFLOW. The largest source and sink terms are represented by precipitation and evapotranspiration, respectively. For the period simulated, a net surplus in the water budget was computed where inflows exceeded outflows by about 1.7 billion cubic feet (0.47 inches per year over the basin area); storage increased by about the same amount to balance the budget. The rate and distribution of recharge throughout the Spring Creek, Nittany Creek, and Spruce Creek Basins is variable as a result of the high degree of hydrogeologic heterogeneity and karst features. The greatest amount of recharge was simulated in the carbonate-bedrock valley, near the toe slopes of Nittany and Tussey Mountains, in the Scotia Barrens, and along the area coinciding with the Gatesburg Formation. Runoff extremes were observed for water years 2001 (dry year) and 2004 (wet year). Simulated average recharge rates (water reaching the saturated zone as defined in GSFLOW) for 2001 and 2004 were 5.4 in/yr and 22.0 in/yr, respectively. Areas where simulations show large variations in annual recharge between wet and dry years are the same areas where simulated recharge was large. Those areas where rates of groundwater recharge are much higher than average, and are capable of accepting substantially greater quantities of recharge during wet years, might be considered critical for maintaining the flow of springs, stream base flow, or the source of water to supply wells. The slopes of the Bald Eagle, Tussey, and Nittany Mountains are relatively insensitive to variations in recharge, primarily because of reduced infiltration rates and steep slopes.

Pennsylvania↗
USGS2024

Least Bell's Vireos and Southwestern Willow Flycatchers—Breeding activities and habitat use—2023 annual report

Executive Summary We completed four protocol surveys for Least Bell’s Vireos ( Vireo bellii pusillus ; hereinafter vireo) during the breeding season, supplemented by weekly territory monitoring visits between April 6 and July 20 at the San Luis Rey Flood Risk Management Project Area (hereinafter Project Area). We identified a total of 136 territorial male vireos; 121 were confirmed as paired, and 4 were confirmed as single males. For the remaining 11 territories, we were unable to confirm breeding status. In 2023, two transient vireos were detected. The vireo population in the Project Area increased by 2 percent from 2022 to 2023. Populations in southern San Diego County also increased (by 6 percent on the Otay River) or were stable (Salt Creek/Wolf Canyon). In contrast, the vireo population at Marine Corps Base Camp Pendleton (MCBCP) and at Marine Corps Air Station decreased by 2 and 10 percent, respectively. We used an index of treatment (hereinafter Treatment Index) to evaluate the effect of ongoing vegetation clearing on the Project Area vireo population. The Treatment Index measures the cumulative effect of vegetation treatment within a territory by using the percentage area treated weighted by the number of years since treatment. We determined that the Treatment Index for an unoccupied habitat was more than four times higher than that of an occupied habitat, indicating that vireos selected habitats that were less treated in which to settle. We monitored vireo nests at three general site types: (1) within the flood channel where non-native and native vegetation removal has occurred regularly (hereinafter Channel), (2) three sites near the flood channel where limited non-native and native vegetation removal has occurred (hereinafter Off-channel), and (3) three sites that have been actively restored by planting native vegetation (hereinafter Restoration). Nesting activity was monitored in 84 territories, 4 of which were occupied by single males. Overall, 46 percent of completed nests were successful, and nest success did not differ among the three sites. In 2023, we found that territories in the Channel had greater hatching success per egg compared to Off-channel, but there were no other differences with regard to clutch size, hatching, or fledging success among Channel, Off-channel, and Restoration sites. Overall breeding success and productivity were slightly higher in 2023 than in 2022, with pairs fledging an average±standard deviation of 3.1±2.1 young and 79 percent of pairs fledging at least 1 young. To investigate if the cumulative years of treatment had an effect on vireo reproductive effort, we looked at the effects of the Treatment Index on reproductive parameters. Results from generalized linear models indicated that treatment did not have an effect on vireo nesting effort (the number of nest attempts) or the number of vireo fledglings per pair produced in 2023. Similarly, we did not detect an effect of Treatment Index on the daily survival rate (DSR) of nests. Analysis of vegetation data collected at vireo nests from 2006 to 2023 did not reveal an effect of vegetation cover at the nest on DSR. We did find, however, that Channel nests were placed higher in and farther from the edge of the host plant than Off-channel nests. Within sites, we did not detect any differences in vegetation cover between successful and unsuccessful nests. Red/arroyo willow ( Salix laevigata or Salix lasiolepis ) and mule fat ( Baccharis salicifolia ) were the species most commonly selected for nesting by vireos in all three site types. Black willow ( Salix gooddingii ) and sandbar willow ( Salix exigua ) also were commonly used. Vireos used a wider variety of species for nesting in Channel and Off-channel sites (10 and 13 species, respectively) compared to Restoration sites (2 species), although there was limited nesting in Restoration sites in 2023. There were 51 vireos banded before the 2023 breeding season that were resighted and identified at the Project Area in 2023. Two of these vireos were originally banded outside of the Project Area, at the Santa Margarita River on MCBCP. Adult birds of known age ranged from 1 to 7 years old. Between 2006 and 2023, survival of males (66±11 percent) was consistently higher than that of females (60±12 percent). First-year birds from 2006 to 2022 had an average annual survival of 15±5 percent. First-year dispersal in 2023 averaged 20.2±31.3 kilometers (km), with the longest dispersal (76.3 km) by a female that was recaptured at Wolf Canyon, a tributary to Otay River. From 2007 to 2012, most returning first-year vireos returned to the Project Area, whereas from 2014 to 2016, a greater proportion of returning birds dispersed to areas outside of the Project Area. From 2018 to 2022, the trend shifted, and more first-year vireos returned to the Project Area, except for 2022 when only one out of five first-year vireos returned to the Project Area. This trend continued in 2023: 71 percent of all first-year vireos returned to the Project Area, and 29 percent dispersed to areas outside of the Project Area (San Diego River and Wolf Canyon). Most of the returning adult male vireos showed strong between-year fidelity to their previous territories. In 2023, 94 percent of males (34/36) occupied a territory that they had defended in 2022 (within 100 meters [m]). In 2023, 33 percent of females (1/3) detected returned to a territory they occupied in 2022. The average between-year movement for returning adult vireos was 0.2±0.9 km. The amount of treatment at adults’ 2022 territories did not affect the distance adults moved to their 2023 territories. We completed four protocol surveys for the endangered Southwestern Willow Flycatcher ( Empidonax traillii extimus ; hereinafter flycatcher) at the Project Area between May 15 and July 21, 2023. In 2023, four transient Willow Flycatchers were detected in the Project Area. Two transients were detected in Reach 1, one in Reach 3a, and one in Whelan Mitigation. No resident flycatchers were documented in the Project Area in 2023. A total of 46 vegetation transects (516 points) were sampled in the Project Area in 2023. There were 71 percent (368/516) of points located in the Channel, and 22 percent (113/516) were in Upper Pond. The remaining 7 percent (35/516) of points were at the Whelan Restoration site. Foliage cover below 1 m was higher at the Channel points and Upper Pond compared to Whelan Restoration. From 1 to 3 m, foliage cover was similar at all 3 sites; however, above 3 m foliage cover was higher in the Channel compared to the Upper Pond and Whelan Restoration sites. Average canopy height was higher in the Channel (5.6±3.8 m) compared to Upper Pond (4.7±2.7 m) and Whelan Restoration (4.0±2.0 m). From 2006 to 2023, total foliage cover declined from 2 to 3 m and above 6 m in the Channel, in contrast to Upper Pond and Whelan Restoration, where little directional change in vegetation cover has occurred and where vegetation cover has largely recovered to 2006 levels. Within the Channel, the steepest declines occurred between 2009 and 2013 and between 2014 and 2016. Since 2016, we observed an increase in foliage cover, largely herbaceous, between 0 and 2 m within the Channel. Although increases were observed at all height classes after 2016, percentage cover has remained below levels measured before 2009. We sampled vegetation at 45 vireo nests and 45 random plots (territory plots) within territories in the Channel and Upper Pond after the 2023 breeding season. Vireos in the Channel established territories in areas with significantly more cover from 3 to 7 m but less cover below 1 m relative to the available habitat. Within territories, Channel vireos selected nest sites largely at random, but with significantly less foliage cover from 4 to 5 m. Vireos at Upper Pond established territories in areas with significantly more foliage cover below 4 m and from 5 to 6 m relative to available habitat. Within territories, Upper Pond vireos also selected nest sites at random except for a preference for sites with significantly less foliage cover below 1 m.

Open-File Report↗
USGS2012

Near-field receiving water monitoring of trace metals and a benthic community near the Palo Alto Regional Water Quality Control Plant in south San Francisco Bay, California: 2011

Trace-metal concentrations in sediment and in the clam Macoma petalum (formerly reported as Macoma balthica), clam reproductive activity, and benthic macroinvertebrate community structure were investigated in a mudflat 1 kilometer south of the discharge of the Palo Alto Regional Water Quality Control Plant (PARWQCP) in South San Francisco Bay, Calif. This report includes the data collected by U.S. Geological Survey (USGS) scientists for the period January 2011 to December 2011. These data serve as the basis for the City of Palo Alto's Near-Field Receiving Water Monitoring Program, initiated in 1994. Following significant reductions in the late 1980s, silver (Ag) and copper (Cu) concentrations in sediment and M. petalum appear to have stabilized. Data for other metals, including chromium, mercury, nickel, selenium, and zinc, have been collected since 1994. Over this period, concentrations of these elements have remained relatively constant, aside from seasonal variation that is common to all elements. In 2011, concentrations of Ag and Cu in M. petalum varied seasonally in response to a combination of site-specific metal exposures and annual growth and reproduction, as reported previously. Seasonal patterns for other elements, including Cr, Hg, Ni, Se, and Zn, were generally similar in timing and magnitude as those for Ag and Cu. In 2011, metal concentrations in both sediments and clam tissue were among the lowest concentrations on record. This record suggests that regional-scale factors now largely control sedimentary and bioavailable concentrations of Ag and Cu, as well as other elements of regulatory interest, at the Palo Alto site. Analyses of the benthic community structure of a mudflat in South San Francisco Bay over a 38-year period show that changes in the community have occurred concurrent with reduced concentrations of metals in the sediment and in the tissues of the biosentinel clam, M. petalum, from the same area. Analysis of the M. petalum community shows increases in reproductive activity concurrent with the decline in metal concentrations in the tissues of this organism. Reproductive activity is presently stable (2011), with almost all animals initiating reproduction in the fall and spawning the following spring. The community has shifted from being dominated by several opportunistic species to a community where the species are more similar in abundance, a pattern that indicates a more stable community that is subjected to fewer stressors. In addition, two of the opportunistic species (Ampelisca abdita and Streblospio benedicti) that brood their young and live on the surface of the sediment in tubes have shown a continual decline in dominance coincident with the decline in metals; both species had short-lived rebounds in abundance in 2008, 2009, and 2010. Heteromastus filiformis (a subsurface polychaete worm that lives in the sediment, consumes sediment and organic particles residing in the sediment, and reproduces by laying its eggs on or in the sediment) showed a concurrent increase in dominance and, in the last several years before 2008, showed a stable population. H. filiformis abundance increased slightly in 2011. An unidentified disturbance occurred on the mudflat in early 2008 that resulted in the loss of the benthic animals, except for those deep-dwelling animals like Macoma petalum. Animals immediately returned to the mudflat in 2008, which was the first indication that the disturbance was not due to a persistent toxin or to anoxia. The reproductive mode of most species present in 2011 is reflective of the species that were available either as pelagic larvae or as mobile adults. Although egg layers were lower in number in this group, the authors hypothesize that these species will return slowly as more species move back into the area. The use of functional ecology was highlighted in the 2011 benthic community data, which show that the animals that have now returned to the mudflat are those that can respond successfully to a physical, nontoxic disturbance. Today, community data show a mix of animals that consume the sediment, filter feed, have pelagic larvae that must survive landing on the sediment, and brood their young. USGS scientists continue to observe the community's response to the 2008 defaunation event because it allows them to examine the response of the community to a natural disturbance (possible causes include sediment accretion or freshwater inundation) and compare this recovery to the long-term recovery observed in the 1970s when the decline in sediment pollutants was the dominating factor.

California↗