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USGS2020

Continuous stream discharge, salinity, and associated data collected in the Lower St. Johns River and its tributaries, Florida, 2018

The U.S. Army Corps of Engineers, Jacksonville District, plans to deepen the St. Johns River channel in Jacksonville, Florida, from 40 to 47 feet along 13 miles of the river channel, beginning at the mouth of the river at the Atlantic Ocean, in order to accommodate larger, fully loaded cargo vessels. The U.S. Geological Survey, in cooperation with the U.S. Army Corps of Engineers, monitored stage, discharge, and (or) water temperature and salinity at 26 continuous data collection stations in the St. Johns River and its tributaries. This is the third annual report by the U.S. Geological Survey on data collection for the Jacksonville Harbor deepening project and contains information pertinent to the data collection during the 2018 water year, from October 2017 to September 2018. Changes to the network on the main stem of the St. Johns River include the addition of (1) three new stations to monitor water temperature and salinity at Racy Point, Shands Bridge, and above Buckman Bridge; (2) stage data collection at both Buckman Bridge and Dames Point Bridge; and (3) three additional parameters, namely stage, velocity, and streamflow direction, to the St. Johns River at Jacksonville and Dames Point Bridge. Discharge and salinity varied widely during the data collection period, which included residual effects from Hurricane Irma in September 2017 and above-average rainfall for all counties in the project area over the 4-month period from April to July. The annual mean discharge at Durbin Creek was greatest among the tributaries, followed by annual mean discharges at Ortega River, Trout River, Cedar River, Julington Creek, Clapboard Creek, Broward River, Pottsburg Creek, and Dunn Creek. The annual mean discharge for each of the main-stem sites was higher in the 2018 water year than that of the previous 2 years of this study. Among the tributary sites, annual mean salinity was highest at Clapboard Creek, the site closest to the Atlantic Ocean, and lowest at Durbin Creek and Ortega River, the sites farthest from the ocean. Annual mean salinity data from the main-stem sites on the St. Johns River indicate that salinity decreased with distance upstream from the ocean, which is expected. Relative to annual mean salinity calculated since the 2016 water year, annual mean salinity at all monitoring locations was lower for the 2018 water year, except for Durbin Creek, which was the same.

Florida↗
USGS2023

Juvenile salmonid monitoring to assess natural recolonization following removal of Condit Dam on the White Salmon River, Washington, 2016–21

Condit Dam was removed from river kilometer (rkm) 5.3 of the White Salmon River, Washington, in 2011 and 2012 after blocking upstream passage of anadromous fish for nearly 100 years. The dam removal opened habitat upstream and improved habitat downstream with addition of cobble and gravel to a reach depauperate of spawning and rearing habitat. We assessed juvenile anadromous salmonid abundance and distribution in the subbasin from 2016 through 2021 to evaluate the efficacy of natural recolonization. We sampled for outmigrant smolts and other life-history stages at a rotary screw trap at rkm 2.3 and for juvenile abundance at sites in Buck and Rattlesnake Creeks, two primary tributaries upstream from the former dam location. We estimated smolt abundance of steelhead ( Oncorhynchus mykiss ) and coho salmon ( O. kisutch ) at the screw-trap site during most years of the study. High flow and missed trapping days in 2017 precluded estimates, and the trap was not fished during 2020 because of the onset of the COVID-19 pandemic. Steelhead smolt-abundance estimates ranged from 3,581 to 5,851 fish; coho salmon smolt-abundance estimates ranged from 1,093 to 1,773 fish, although in 2021, only 2 coho salmon smolt were captured and no estimate was made. Other species and life stages also were captured in the screw trap. Steelhead and coho salmon fry and parr, and Chinook salmon ( O. tshawytscha ) fry were captured, indicating the presence and likely use of improved habitat downstream from the former dam site by multiple life stages and spawning success upstream from the screw-trap site. Chinook salmon fry were captured, indicating spawning success upstream from the screw-trap site. Fry numbers varied greatly by day and year. Yearly variation in Chinook and coho salmon fry numbers may have been influenced by high flows following spawning causing redd scour and egg-to-fry mortality. Three bull trout ( Salvelinus confluentus ) were caught in the screw trap, one in June 2018, one in June 2019, and one in June 2021. All three bull trout showed smolt characteristics and were tagged with passive integrated transponders (PITs). The bull trout captured in June 2018 was detected at Bonneville Dam Corner Collector several days later, indicating likely anadromy. We also captured lamprey in the screw trap: 44 during 2018, 31 during 2019, and 11 during 2021; we believe most were adult brook lamprey ( Lampetra richardsoni ), although some could have been Pacific lamprey ( Entosphenus tridentatus ) macropthalmia. We confirmed the presence of juvenile steelhead (through smolt origin data) and coho salmon in Mill, Buck, and Rattlesnake Creeks, which are all upstream from the former site of Condit Dam. Juvenile salmonid abundance sampling at a site in Buck Creek during 2016–20 indicated the presence of juvenile coho salmon in all years except 2020. Total salmonid abundance (steelhead and coho salmon combined) at the Buck Creek site each year exceeded abundance in sampling prior to dam removal in 2009 and 2010. Juvenile salmonid abundance sampling in Rattlesnake Creek during 2016–20 indicated the presence of juvenile coho salmon in 2017, 2018, and 2019. Total juvenile salmonid abundance at the Rattlesnake Creek site was highly variable, sometimes exceeding and sometimes less than abundance prior to dam removal during 2001–05. During the period covered by this report, adult salmonid returns to the Columbia River were decreasing, largely because of marine survival. The extent to which this basin-wide decrease affected adult returns and juvenile populations in the White Salmon River subbasin is not known. Despite a period of poor marine survival, PIT-tagged smolt and juvenile steelhead and coho salmon from the screw trap and tributaries returned to Bonneville Dam. Smolt-to-adult return rates from the screw trap to Bonneville Dam were similar to those in other nearby rivers during this period. However, data are still incomplete for some years and sample sizes were low. Future tagging and monitoring would be beneficial to track this valuable metric. Genetic samples from steelhead smolt and parr collected at the screw trap and some main-stem electrofishing during 2016 were analyzed for Genetic Stock Identification (GSI) by CRITFC. Preliminary data showed that White Salmon River fish were the most common at about 42 percent, with 19 percent typing to Hood River, Oregon stock, and about 26 percent typing to Skamania stock, a common hatchery stock in the area. Winter and summer runs were represented in the samples. Juvenile salmonid sampling in the White Salmon River, Washington, following removal of Condit Dam, demonstrated that anadromous salmonids are using newly opened habitat upstream from the former dam site and improved lower river habitat. Steelhead and coho salmon smolts are being produced upstream from the former dam site, and some have returned to Bonneville Dam as adults. Chinook salmon spawning upstream from our smolt trap site are producing fry. These results are encouraging for success of the strictly natural recolonization strategy. However, declines in anadromous runs to the larger Columbia River Basin also likely have affected the White Salmon runs and our data may not reflect full capacity of the White Salmon River subbasin juvenile production. Continued abundance, distribution, and GSI monitoring will help to track the evolution of anadromous fish in the White Salmon River under a natural recolonization strategy.

Washington↗
USGS1972

Potential transport of sediment from Enloe Reservoir by the Similkameen and Okanogan rivers, Washington

This study was undertaken to determine the probable effects on the Similkameen and Okanogan Rivers of the removal, transport, and deposition of sediment now deposited behind Enloe Dam on the Similkameen River, if the dam were removed. Under existing conditions of sediment transport, the average annual suspended-sediment discharges at three streamflow-measuring sites are calculated to be 134,000 tons for the Similkameen River near Nighthawk, 175,000 tons for the Okanogan River near Tonasket, and 175,000 tons for the Okanogan River at Malott. The volume of sediment in Enloe Reservoir was computed to be 1.79 million cubic yards (about 2.4 million tons). The sediment is largely sand. If the dam were removed the maximum amount of reservoir sand transportable (in addition to normal sediment discharge), under stated conditions of velocity and depth during any average 10-year period, would range from about 17,000 to 580,000 cubic yards per year, with about 320,000 cubic yards being transported during a year of average water discharge. These volumes represent a range of 32 to less than 1 percent of the volume of sediment now deposited in the reservoir. The reservoir deposits not carried to the mouth of the Okanogan River (at Columbia River) would be deposited largely in a 17-mile reach of the Okanogon River immediately downstream from its confluence with the Similkameen River. Deposition of the reservoir sediment would tend to reduce the capacity of the channel of the Okanogan River in this reach; also there possibly would be some long-tern adjustments of the stream course to the temporary increase in the sediment load. Locally, the reduction in the channel cross section probably would increase the depth of the water and area of inundation during floods. Deposition of sediment in the Okanogan River channel and accompanying undesirable effects would be less severe if the dam were removed in segments over a period of several years. If the dam is removed in segments the amount of sediment transported by the river could be monitored to evaluate (1) the timing of the removal of the remaining segments of the dam, based on actual sediment-transport data, (2) the amount of sediment rremaining in the reservoit, and (3) the impact of sediment deposition on channel configuration and flooding.

Open-File Report↗
USGS1981

Preliminary water-quality assessment of the upper White River near Indianapolis, Marion County, Indiana

The White River Park Commission is planning the development of park facilities along the White River through Indianapolis. A key element in the planning is the determination of whether water quality of the river is suitable for recreation. A preliminary water-quality assessment of the river in Indianapolis on August 4-5, 1980, indicates that, during low-flow steady-state conditions, water quality of the river is suitable for partial body contact recreation (any contact with water up to, but not including, complete submergence). Dissolved-oxygen concentrations varied but were higher than the Indiana water-quality standards established to ensure conditions for the maintenance of a well-balanced, warm-water fish community. High fecal-coliform densities that have been observed in the White River during high stream-flow are probably caused by stormwater runoff from combined sewers. However, during the low-flow steady-state conditions on August 4-5, 1980, fecal coliform densities were within the Indiana standards for partial body contact recreation. Concentrations of organic matter (based on biochemical-oxygen demand and dissolved- and suspended-organic carbon concentrations), nutrients, and heavy metals in the White River were generally within the limits recommended by the U.S. Environmental Protection Agency and were generally similar to values for other Indiana rivers. Chromium, copper, lead, zinc, and mercury are accumulating in bottom materials downstream from 30th Street (river mile 235.58). The source of these metals is probably stormwater runoff from combined sewer overflows. The phytoplankton densities of the White River were high (>500 cells per milliliter). The dominant phytoplankton species are indicative of rivers moderately affected by organic wastes. The highest cell concentrations, upstream from dams on the White River, significantly affected dissolved-oxygen concentration and pH.

Indiana↗
USGS1996

Progress report on daily flow-routing simulation for the Carson River, California and Nevada

A physically based flow-routing model using Hydrological Simulation Program-FORTRAN (HSPF) was constructed for modeling streamflow in the Carson River at daily time intervals as part of the Truckee-Carson Program of the U.S. Geological Survey (USGS). Daily streamflow data for water years 1978-92 for the mainstem river, tributaries, and irrigation ditches from the East Fork Carson River near Markleeville and West Fork Carson River at Woodfords down to the mainstem Carson River at Fort Churchill upstream from Lahontan Reservoir were obtained from several agencies and were compiled into a comprehensive data base. No previous physically based flow-routing model of the Carson River has incorporated multi-agency streamflow data into a single data base and simulated flow at a daily time interval. Where streamflow data were unavailable or incomplete, hydrologic techniques were used to estimate some flows. For modeling purposes, the Carson River was divided into six segments, which correspond to those used in the Alpine Decree that governs water rights along the river. Hydraulic characteristics were defined for 48 individual stream reaches based on cross-sectional survey data obtained from field surveys and previous studies. Simulation results from the model were compared with available observed and estimated streamflow data. Model testing demonstrated that hydraulic characteristics of the Carson River are adequately represented in the models for a range of flow regimes. Differences between simulated and observed streamflow result mostly from inadequate data characterizing inflow and outflow from the river. Because irrigation return flows are largely unknown, irrigation return flow percentages were used as a calibration parameter to minimize differences between observed and simulated streamflows. Observed and simulated streamflow were compared for daily periods for the full modeled length of the Carson River and for two major subreaches modeled with more detailed input data. Hydrographs and statistics presented in this report describe these differences. A sensitivity analysis of four estimated components of the hydrologic system evaluated which components were significant in the model. Estimated ungaged tributary streamflow is not a significant component of the model during low runoff, but is significant during high runoff. The sensitivity analysis indicates that changes in the estimated irrigation diversion and estimated return flow creates a noticeable change in the statistics. The modeling for this study is preliminary. Results of the model are constrained by current availability and accuracy of observed hydrologic data. Several inflows and outflows of the Carson River are not described by time-series data and therefore are not represented in the model.

Open-File Report↗
USGS1997

Comparison of two methods for estimating discharge and nutrient loads from tidally affected reaches of the Myakka and Peace Rivers, west-central Florida

The Myakka and Peace River Basins constitute more than 60 percent of the total inflow area and contribute more than half the total tributary inflow to the Charlotte Harbor estuarine system. Water discharge and nutrient enrichment have been identified as significant concerns in the estuary, and consequently, it is important to accurately estimate the magnitude of discharges and nutrient loads transported by inflows from both rivers. Two methods for estimating discharge and nutrient loads from tidally affected reaches of the Myakka and Peace Rivers were compared. The first method was a tidal-estimation method, in which discharge and nutrient loads were estimated based on stage, water-velocity, discharge, and water-quality data collected near the mouths of the rivers. The second method was a traditional basin-ratio method in which discharge and nutrient loads at the mouths were estimated from discharge and loads measured at upstream stations. Stage and water-velocity data were collected near the river mouths by submersible instruments, deployed in situ, and discharge measurements were made with an acoustic Doppler current profiler. The data collected near the mouths of the Myakka River and Peace River were filtered, using a low-pass filter, to remove daily mixed-tide effects with periods less than about 2 days. The filtered data from near the river mouths were used to calculate daily mean discharge and nutrient loads. These tidal-estimation-method values were then compared to the basin-ratio-method values. Four separate 30-day periods of differing streamflow conditions were chosen for monitoring and comparison. Discharge and nutrient load estimates computed from the tidal-estimation and basin-ratio methods were most similar during high-flow periods. However, during high flow, the values computed from the tidal-estimation method for the Myakka and Peace Rivers were consistently lower than the values computed from the basin-ratio method. There were substantial differences between discharges and nutrient loads computed from the tidal-estimation and basin-ratio methods during low-flow periods. Furthermore, the differences between the methods were not consistent. Discharges and nutrient loads computed from the tidal-estimation method for the Myakka River were higher than those computed from the basin-ratio method, whereas discharges and nutrients loads computed by the tidal-estimation method for the Peace River were not only lower than those computed from the basin-ratio method, but they actually reflected a negative, or upstream, net movement. Short-term tidal measurement results should be used with caution, because antecedent conditions can influence the discharge and nutrient loads. Continuous tidal data collected over a 1- or 2-year period would be necessary to more accurately estimate the tidally affected discharge and nutrient loads for the Myakka and Peace River Basins.

Florida↗
USGS1997

Transport of diazinon in the San Joaquin River basin, California

Most of the application of the organophosphate insecticide diazinon in the San Joaquin River Basin occurs in winter to control wood boring insects in dormant almond orchards. A federal-state collaborative study found that diazinon accounted for most of the observed toxicity of San Joaquin River water to water fleas in February 1993. Previous studies focussed mainly on west-side inputs to the San Joaquin River. In this 1994 study, the three major east-side tributaries to the San Joaquin River, the Merced, Tuolumne, and Stanislaus Rivers, and a downstream site on the San Joaquin River were sampled throughout the hydrographs of a late January and an early February storm. In both storms, the Tuolumne River had the highest concentrations of diazinon and transported the largest load of the three tributaries. The Stanislaus River was a small source in both storms. On the basis of previous storm sampling and estimated traveltimes, ephemeral west-side creeks were probably the main diazinon source early in the storms, while the Tuolumne and Merced Rivers and east-side drainage directly to the San Joaquin River were the main sources later. Although 74 percent of diazinon transport in the San Joaquin River during 199193 occurred in January and February, transport during each of the two 1994 storms was only 0.05 percent of the amount applied during preceeding dry periods. Nevertheless, some of the diazinon concentrations in the San Joaquin River during the January storm exceeded 0.35 micrograms per liter, a concentration shown to be acutely toxic to water fleas. Diazinon concentrations were highly variable during the storms and frequent sampling was required to adequately describe the concentration curves and to estimate loads.

Open-File Report↗
USGS1998

Transport of sediment-bound organochlorine pesticides to the San Joaquin River, California

Most of the application of the organophosphate insecticide diazinon in the San Joaquin River Basin occurs in winter to control wood boring insects in dormant almond orchards. A federal-state collaborative study found that diazinon accounted for most of the observed toxicity of San Joaquin River water to water fleas in February 1993. Previous studies focused mainly on west-side inputs to the San Joaquin River. In this 1994 study, the three major east-side tributaries to the San Joaquin River, the Merced, Tuolumne, and Stanislaus Rivers, and a downstream site on the San Joaquin River were sampled throughout the hydrographs of a late January and an early February storm. In both storms, the Tuolumne River had the highest concentrations of diazinon and transported the largest load of the three tributaries. The Stanislaus River was a small source in both storms. On the basis of previous storm sampling and estimated traveltimes, ephemeral west-side creeks probably were the main diazinon source early in the storms, whereas the Tuolumne and Merced Rivers and east-side drainages directly to the San Joaquin River were the main sources later. Although 74 percent of diazinon transport in the San Joaquin River during 1991-1993 occurred in January and February, transport during each of the two 1994 storms was only 0.05 percent of the amount applied during preceding dry periods. Nevertheless, some of the diazinon concentrations in the San Joaquin River during the January storm exceeded 0.35 micrograms per liter, a concentration shown to be acutely toxic to water fleas. Diazinon concentrations were highly variable during the storms and frequent sampling was required to adequately describe the concentration curves and to estimate loads.

Open-File Report↗
USGS1998

Water-quality characteristics of the Slate and East rivers, Colorado, during the winter recreational season, December 1996

Periods of population influxes during winter recreation occur simultaneously with periods of extreme low flow in many Rocky Mountain areas. The ability of streams to assimilate additional nutrient loading is reduced by the low-flow conditions. Low-flow water-quality characteristics of the Slate and East Rivers, which drain the Crested Butte area, were investigated in December 1996. Six sites were chosen for evaluation-four on the Slate River and two on the East River-to assess water-quality conditions, including nutrient (nitrogen and phosphorus) concentrations and algal biomass, during a 24-hour period. Discharge in the Slate River ranged from about 18 to 30 cubic feet per second, and discharge in the East River downstream from the mouth of the Slate River was about 80 cubic feet per second. Chemical concentrations in water in the Slate and East Rivers generally were dilute with specific-conductance values of 175 to 300 microsiemens per centimeter and alkalinity values of 40 to 110 milligrams per liter during low-flow conditions. Dissolved oxygen was at or near saturation at all measurements sites. Ammonia nitrogen concentrations increased downstream from Crested Butte and Mount Crested Butte in the Slate River and then returned to background concentrations in the East River. Concentrations of nitrite plus nitrate nitrogen increased downstream from the Crested Butte area, probably associated with the nitrification of the ammonia to nitrate, and concentrations then were diluted in the East River downstream from the confluence of the Slate River. Phosphorus concentrations also increased slightly in the reach downstream from Crested Butte and Mount Crested Butte. Algal biomass values increased downstream from the Crested Butte area, decreased to low values in a subsequent reach, and then returned to higher values downstream. Biomass values were similar to those found in unenriched to moderately enriched streams. The lower biomass and higher phosphorus values occurred in a reach that was covered completely with ice and snow. Algal biomass in this reach was extremely low, probably due to the absence of light. The biomass values upstream and downstream from this reach were moderately high and probably resulted in the lower phosphorus and possibly somewhat lower nitrogen, which suggests that benthic algae may be partially controlling the nutrient levels through assimilation and uptake. When light conditions restrict algal growth and subsequent loading occurs, the concentrations of phosphorus increase slightly. Once the physical limitation (absence of light) is removed, the biomass responds with a corresponding decrease in phosphorus. The nutrient concentrations were low and well below stream standards. Nutrient increases were measured downstream from Crested Butte and Mount Crested Butte, and these increases resulted in an increase of algal biomass. Overall results indicate that, at the present time, the Slate and East Rivers can assimilate winter low-flow nutrient loads.

Colorado↗
USGS1998

Concepts for monitoring water quality in the Spokane River Basin, northern Idaho and eastern Washington

Numerous environmental studies have been conducted in the Spokane River Basin over the past several decades by government agencies, academic institutions, and environmental engineering firms. Most of these efforts have focused on the environmental effects of more than a century of silver, lead, and zinc mining and oreprocessing activities in the South Fork Coeur d'Alene River valley in northern Idaho. Several studies also have assessed the water quality and potential for eutrophication of Coeur d'Alene and Long Lakes and the Coeur d'Alene, St. Joe, and Spokane Rivers. Because past investigations often were limited in scope and employed different approaches and methods, an integrated understanding of hydrologic, water-quality, and aquatic biological conditions still is lacking for the basin as a whole. Substantial resources are being spent for water-quality and naturalresource management, and for mitigating the adverse environmental effects of past mining activities in the basin. A water-quality monitoring network, integrated with the decision-making processes associated with these efforts, could be of considerable value. The purpose of such a monitoring network is to produce high-quality information on which to base sound water-quality and natural-resource management decisions and to assess the effectiveness of those decisions. A streamflow- and water-quality monitoring infrastructure already exists in the Spokane River Basin. This infrastructure consists of 20 lake-stage and streamflow-gaging stations, representing specific drainages or subdrainages and, in many cases, specific stream reaches or subreaches. These gaging stations are operated by the U.S. Geological Survey (USGS), several of them in cooperation with State and Federal agencies and a private utility company. Extensive streamflow data are available, some dating from the late 1800s. Water-quality data are also available from recent USGS cooperative studies in the Coeur d'Alene Lake watershed. A nutrient load/lake response (eutrophication) model has been developed for Coeur d'Alene Lake. Hydraulic models for estimating streamflow through the low-gradient reaches of the Coeur d'Alene and St. Joe Rivers have been developed. Trace-element concentrations and distributions in sediments in the lower South Fork and main-stem Coeur d'Alene River flood plain and the bed of Coeur d'Alene Lake have been assessed. Trace-element transport models have been developed for the lower Coeur d'Alene River system; estimates of annual load are available from the early 1990's to the present (1998). The USGS is monitoring traceelement concentrations and transport at seven gaging stations in the lower Coeur d'Alene River system and upper Spokane River, in cooperation with the U.S. Environmental Protection Agency. Fish and macroinvertebrate community assessment and tissue contaminant analyses at four Coeur d'Alene and St. Joe River gaging stations will begin in 1998, either as part of the Idaho Surface- Water Quality Ambient Monitoring Network operated by USGS in cooperation with the Idaho Division of Environmental Quality, or for the Northern Rockies Intermontane Basins (NROK) study of the USGS National Water-Quality Assessment (NAWQA) Program. Several gaging stations in the Spokane River Basin are being considered for routine sampling sites for the NROK NAWQA study. Several other sites also will be sampled for contaminants in bed sediment and fish tissue for the NROK study. Combined with appropriate sampling and data interpretation strategies, the existing USGS gaging-station network and data base could provide integrated water-quality information needed for sound environmental and resource-management decisions throughout the Spokane River Basin.

Idaho;Washington↗
USGS2008

Nutrient Concentrations and Their Relations to the Biotic Integrity of Nonwadeable Rivers in Wisconsin

Excessive nutrient [phosphorus (P) and nitrogen (N)] input from point and nonpoint sources is frequently associated with degraded water quality in streams and rivers. Point-source discharges of nutrients are fairly constant and are controlled by the U.S. Environmental Protection Agency's (USEPA) National Pollutant Discharge Elimination System. To reduce inputs from nonpoint sources, agricultural performance standards and regulations for croplands and livestock operations are being proposed by various States. In addition, the USEPA is establishing regionally based nutrient criteria that can be refined by each State to determine whether actions are needed to improve water quality. More confidence in the environmental benefits of the proposed performance standards and nutrient criteria would be possible with improved understanding of the biotic responses to a range of nutrient concentrations in different environmental settings. To achieve this general goal, the U.S. Geological Survey and the Wisconsin Department of Natural Resources collected data from 282 streams and rivers throughout Wisconsin during 2001 through 2003 to: (1) describe how nutrient concentrations and biotic-community structure differ throughout the State, (2) determine which environmental characteristics are most strongly related to the distribution of nutrient concentrations and biotic-community structure, (3) determine reference conditions for water quality and biotic indices for streams and rivers in the State, (4) determine how the biotic communities in streams and rivers in different areas of the State respond to differences in nutrient concentrations, (5) determine the best regionalization scheme to describe the patterns in reference conditions and the corresponding responses in water quality and the biotic communities (primarily for smaller streams), and (6) develop algorithms to estimate nutrient concentrations in streams and rivers from a combination of biotic indices. The ultimate goal of this study is to provide the information needed to guide the development of regionally based nutrient criteria for Wisconsin streams and rivers. In this report, data collected, primarily in 2003, from 42 nonwadeable rivers are used to describe nutrient concentrations and their relations to the biotic integrity of rivers in Wisconsin. In a separate report by Robertson and others (2006a), the data collected from 240 wadeable streams are used to describe these relations in streams in Wisconsin. Reference water-quality conditions for nonwadeable rivers were found to be similar throughout Wisconsin (approximately 0.035 milligrams per liter (mg/L) for total P (TP), 0.500 mg/L for total N (TN), 4 micrograms per liter for suspended chlorophyll a (SCHL), and greater than 110 centimeters for Secchi-tube depth (SD)). For each category of the biotic community (SCHL, macroinvertebrates, and fish), a few indices were more strongly related to differences in nutrient concentrations than were others. For the indices most strongly related to nutrient concentrations, reference conditions were obtained with a regression approach, from values corresponding to the worst 75th-percentile value from a subset of minimally impacted streams (streams having reference nutrient concentrations), and from the best 25th-percentile value of all the data. Concentrations of TP and TN in nonwadeable rivers increased as the percentage of agricultural land in the basin increased; these increases resulted in increased SCHL concentrations and decreased SDs. The responses in SDs and SCHL concentrations to changes in nutrient concentrations were similar throughout most of the State except in rivers in the southeastern part, where SCHL concentrations were lower than would be expected given their nutrient concentrations. Rivers in the southeastern part of the State had high concentrations of total suspended sediment compared to the SCHL concentrations. Many biotic indices responded to increases in nu

Professional Paper↗
USGS2004

Water Quality and Streamflow of the Indian River, Sitka, Alaska, 2001-02

The Indian River Basin, located near Sitka Alaska, drains an area of 12.3 square miles. This watershed is an important natural resource of Sitka National Historic Park. At the present time, the watershed faces possible development on large tracts of private land upstream of the park that could affect the water quality of Indian River. Due to this concern, a study was conducted cooperatively with the National Park Service. The approach was to examine the water quality of the Indian River in the upper part of the watershed where no development has occurred and in the lower part of the basin where development has taken place. Measurements of pH, water temperature, and dissolved oxygen concentrations of the Indian River were within acceptable ranges for fish survival. The Indian River is calcium bicarbonate type water with a low buffering capacity. Concentrations of dissolved ions and nutrients generally were low and exhibited little variation between the two study sites. Analysis of bed sediment trace element concentrations at both sampling sites indicates the threshold effect concentration was exceeded for arsenic, chromium, copper, nickel, and zinc; while the probable effect concentration was exceeded by arsenic, chromium and nickel. However, due to relatively large amounts of organic carbon present in the bed sediments, the potential toxicity from trace elements is low. Discharge in the Indian River is typical of coastal southeast Alaska streams where low flows generally are in late winter and early spring and greater flows are during the wetter fall months. Alaska Department of Fish and Game has established instream flow reservations on the lower 2.5 miles of the Indian River. Discharge data indicate minimum flow requirements were not achieved during 236 days of the study period. Natural low flows are frequently below the flow reservations, but diversions resulted in flow reservations not being met a total of 140 days. Thirty-five algae species were identified from the sample collected at Indian River near Sitka while 24 species were identified from the sample collected at Indian River at Sitka. Most species of algae identified in the Indian River samples were diatoms and the majority were pinnate diatoms; however, green algae and (or) blue-green algae accounted for much of the algal biomass at the two sites. The trophic condition of the Indian River is oligotrophic, and algal productivity likely is limited by low concentrations of dissolved nitrogen. Few invertebrate taxa were collected relative to many high-quality streams in the contiguous United States, but the number of taxa in Indian River appears to be typical of Alaska streams. Ephemeroptera was the most abundant order sampled followed by Diptera.

Scientific Investigations Report↗
USGS2004

Questa baseline and pre-mining ground-water quality investigation 4. Historical surface-water quality for the Red River Valley, New Mexico, 1965 to 2001

Historical water-quality samples collected from the Red River over the past 35 years were compiled, reviewed for quality, and evaluated to determine influences on water quality over time. Hydrologic conditions in the Red River were found to have a major effect on water quality. The lowest sulfate concentrations were associated with the highest flow events, especially peak, rising limb, and falling limb conditions. The highest sulfate concentrations were associated with the early part of the rising limb of summer thunderstorm events and early snowmelt runoff, transient events that can be difficult to capture as part of planned sampling programs but were observed in some of the data. The first increase in flows in the spring, or during summer thunderstorm events, causes a flushing of sulfide oxidation products from scars and mine-disturbed areas to the Red River before being diluted by rising river waters. A trend of increasing sulfate concentrations and loads over long time periods also was noted at the Questa Ranger Station gage on the Red River, possibly related to mining activities, because the same trend is not apparent for concentrations upstream. This trend was only apparent when the dynamic events of snowmelt and summer rainstorms were eliminated and only low-flow concentrations were considered. An increase in sulfate concentrations and loads over time was not seen at locations upstream from the Molycorp, Inc., molybdenum mine and downstream from scar areas. Sulfate concentrations and loads and zinc concentrations downstream from the mine were uniformly higher, and alkalinity values were consistently lower, than those upstream from the mine, suggesting that additional sources of sulfate, zinc, and acidity enter the river in the vicinity of the mine. During storm events, alkalinity values decreased both upstream and downstream of the mine, indicating that natural sources, most likely scar areas, can cause short-term changes in the buffering capacity of the Red River. The major-element water chemistry of the Red River is controlled by dissolution of calcite and gypsum and the oxidation of pyrite, and the river is generally not well buffered with respect to pH. During higher-flow periods, Red River water was diluted by calcium-carbonate waters, most likely from unmineralized Red River tributaries and areas upstream from scars. The effect of pyrite oxidation on Red River water chemistry was more pronounced after the early 1980's. Elevated zinc concentrations were most apparent during summer thunderstorm and rising limb times, which also were associated with a decrease in alkalinity and an increase in sulfate concentrations and conductivity. The water-quality results demonstrate that it is critical to consider hydrologic conditions when interpreting water chemistry in naturally mineralized or mined drainages.

New Mexico↗
USGS2004

Comparison of methods for determining streamflow requirements for aquatic habitat protection at selected sites on the Assabet and Charles Rivers, Eastern Massachusetts, 2000-02

Four methods used to determine streamflow requirements for habitat protection at nine critical riffle reaches in the Assabet River and Charles River Basins were compared. The methods include three standard setting techniques?R2Cross, Wetted Perimeter, and Tennant?and a diagnostic method, the Range of Variability Approach. One study reach is on the main stem of the Assabet River, four reaches are on tributaries to the Assabet River (Cold Harbor Brook, Danforth Brook, Fort Meadow Brook, and Elizabeth Brook), three are on the main stem of the Charles River, and one is on a tributary to the Charles River (Mine Brook). The strength of the R2Cross and Wetted-Perimeter methods is that they may be applied at ungaged locations whereas the Tennant method and the Range of Variability Approach require a period of streamflow record for analysis. Fish community assessments conducted at or near riffle sites in flowing reaches of the Assabet River and Charles River Basins were used to indicate ecological conditions. The fish communities in the main stem and tributary reaches of both the Assabet and Charles River Basins indicated degraded aquatic ecosystems. However, the degree of degradation differs between the two basins. The extreme predominance of tolerant, generalist species in the Charles River fish community demon-strates the cumulative impacts of flow, habitat, and water-chemistry degradation, combined with the effects of nearby impoundments and changing land use. The range of discharges for nine ungaged riffle reaches defined by the median R2Cross 3-of-3 criteria, R2Cross 2-of-3 criteria, and Wetted-Perimeter streamflow requirements, was 0.86 cubic foot per second per square mile, 0.18 cubic foot per second per square mile, and 0.23 cubic foot per second per square mile, respectively. Application of R2Cross and Wetted-Perimeter methods to sites with altered streamflows or at sites that are riffles only at low to moderate flows can result in a greater variability of streamflow requirements than would result if the methods were applied to riffles on natural channels with unaltered streamflows. The R2Cross 2-of-3 criteria and the Wetted-Perimeter streamflow requirements for the Assabet and Charles River sites show narrower interquartile ranges and lower median streamflow requirements than for 10 index streamflow-gaging stations in southern New England. This is especially evident for the R2Cross 2-of-3 criteria and Wetted-Perimeter results that were close to half of the flow requirements determined at the 10 southern New England stations. The R2Cross and Wetted-Perimeter methods were also compared to the Range of Variability Approach analysis and the Tennant Method. The median R2Cross 3-of-3 criteria streamflow requirement for the nine riffles is close to the 75th percentile of the monthly mean flows during the summer low-flow period from six streamflow-gaging stations near the Assabet and Charles River Basins having mostly unaltered flow. This streamflow requirement is close to the median Tennant 40-percent-flow requirement for good habitat condi-tion for the same six nearby stations. The R2Cross 2-of-3 criteria and Wetted-Perimeter results were less than the 25th-percentile of monthly mean flows during the summer months for the six stations. These streamflow requirements are in the poor habitat range as indicated by a Tennant analysis of the same six stations. These comparisons indicate that the R2Cross and Wetted-Perimeter methods underestimate streamflow requirements when applied to sites in smaller drainage areas and channels that are runs at higher flows.

Scientific Investigations Report↗
USGS2004

Simulation of ground-water flow in the Cedar River alluvial aquifer flow system, Cedar Rapids, Iowa

The Cedar River alluvial aquifer is the primary source of municipal water in the Cedar Rapids, Iowa, area. Since 1992, the U.S. Geological Survey, in cooperation with the City of Cedar Rapids, has investigated the hydrogeology and water quality of the Cedar River alluvial aquifer. This report describes a detailed analysis of the ground-water flow system in the alluvial aquifer, particularly near well field areas. The ground-water flow system in the Cedar Rapids area consists of two main components, the unconsolidated Quaternary deposits and the underlying carbonate bedrock that has a variable fracture density. Quaternary deposits consist of eolian sand, loess, alluvium, and glacial till. Devonian and Silurian bedrock aquifers overlie the Maquoketa Shale (Formation) of Ordovician age, a regional confining unit. Ground-water and surface-water data were collected during the study to better define the hydrogeology of the Cedar River alluvial aquifer and Devonian and Silurian aquifers. Stream stage and discharge, ground-water levels, and estimates of aquifer hydraulic properties were used to develop a conceptual ground-water flow model and to construct and calibrate a model of the flow system. This model was used to quantify the movement of water between the various components of the aluvial aquifer flow system and provide an improved understanding of the hydrology of the alluvial aquifer. Ground-water flow was simulated for the Cedar River alluvial aquifer and the Devonian and Silurian aquifers using the three-dimensional finite-difference ground-water flow model MODFLOW. The model was discretized into 223 rows and 354 columns of cells. Areal cell sizes range from about 50 feet on a side near the Cedar River and the Cedar Rapids municipal wells to 1,500 feet on a side near the model boundaries and farthest away from the Cedar Rapids municipal well fields. The model is separated into five layers to account for the various hydrogeologic units in the model area. Model results indicate that the primary sources of inflow to the modeled area are infiltration from the Cedar River (53.0 percent) and regional flow in the glacial and bedrock materials (34.1 percent). The primary sources of outflow from the modeled area are discharge to the Cedar River (45.4 percent) and pumpage (44.8 percent). Current steady-state pumping rates have increased the flow of water from the Cedar River to the alluvial aquifer by 43.8 cubic feet per second. Steady-state and transient hypothetical pumpage scenarios were used to show the relation between changes in pumpage and changes in infiltration of water from the Cedar River. Results indicate that more than 99 percent of the water discharging from municipal wells infiltrates from the Cedar River, that the time required for induced river recharge to equilibrate with municipal pumpage may be 150 days or more, and that ground-water availability in the Cedar Rapids area will not be significantly affected by doubling current pumpage as long as there is sufficient flow in the Cedar River to provide recharge.

Iowa↗
USGS2004

Nutrient enrichment, phytoplankton algal growth, and estimated rates of instream metabolic processes in the Quinebaug River Basin, Connecticut, 2000-2001

A consistent and pervasive pattern of nutrient enrichment was substantiated by water-quality sampling in the Quinebaug River and its tributaries in eastern Connecticut during water years 2000 and 2001. Median total nitrogen and total phosphorus concentrations exceeded the U.S. Environmental Protection Agency?s recently recommended regional ambient water-qual-ity criteria for streams (0.71 and 0.031 milligrams per liter, respectively). Maximum total phosphorus concentrations exceeded 0.1 milligrams per liter at nearly half the sampled locations in the Quinebaug River Basin. Elevated total nitrogen and total phosphorus concentrations were measured at all stations on the mainstem of the Quinebaug River, the French River, and the Little River. Nutrient enrichment was related to municipal wastewater point sources at the sites on the mainstem of the Quinebaug River and French River, and to agricultural nonpoint nutrient sources in the Little River Basin. Nutrient enrichment and favorable physical factors have resulted in excessive, nuisance algal blooms during summer months, particularly in the numerous impoundments in the Quinebaug River system. Phytoplankton algal density as high as 85,000 cells per milliliter was measured during such nuisance blooms in water years 2000 and 2001. Different hydrologic conditions during the summers of 2000 and 2001 produced very different seston algal populations. Larger amounts of precipitation sustained higher streamflows in the summer of 2000 (than in 2001), which resulted in lower total algal abundance and inhibited the typical algal succession from diatoms to cyanobacteria. Despite this, nearly half of all seston chlorophyll-a concentrations measured during this study exceeded the recommended regional ambient stream-water-quality criterion (3.75 micrograms per liter), and seston chlorophyll-a concentrations as large as 42 micrograms per liter were observed in wastewa-ter-receiving reaches of the Quinebaug River. Estimates of primary productivity and respiration obtained from diel dissolved oxygen monitoring and from light- and dark-bottle dissolved oxygen measurements demonstrated that instream metabolic processes are consistent with a seston-algae dominant system. The highest estimated maximum primary productivity rate was 1.72 grams of oxygen per cubic meter per hour at the Quinebaug River at Jewett City during September 2001. The observed extremes in diel dissolved oxygen concentrations (less than 5 milligrams per liter) and pH (greater than 9) may periodically stress aquatic organisms in the Quinebaug River Basin.

Scientific Investigations Report↗
USGS2005

Base flow, water quality, and streamflow gain and loss of the Buffalo River, Arkansas, and selected tributaries, July and August 2003

A study of the Buffalo National River in north-central Arkansas was conducted between July 28-30 and August 13-15, 2003, to characterize the base-flow and water-quality characteristics and streamflow gain and loss in the Buffalo River. The study was separated into two time periods because of a precipitation event that occurred on the afternoon of July 30 causing appreciable storm runoff. Streamflow was separated to identify base-flow and surface-runoff components using the Base Flow Index hydrograph separation computer program. Base-flow separation analyses indicated annual variability in streamflow throughout the Buffalo River Basin. Based upon these analyses, total and base flow were below average for the mainstem of the river and Richland Creek during the 2003 water year. Waterquality samples were collected from 25 surface-water sites on the Buffalo River and selected tributaries. Most nutrient concentrations for the mainstem of the Buffalo River were near or below the minimum reporting level and were less than the median flow-weighted concentration for relatively undeveloped stream basins in the United States. Streamflow measurement data were collected at 44 locations along the mainstem of the Buffalo River and at points of inflow (prior to confluence with the mainstem) to identify gaining and losing reaches. Seven gaining and five losing reaches were identified for the Buffalo River. Additionally, surface flow on the mainstem of the Buffalo River was diverted to subsurface flow on the mainstem at two locations (river miles 73.6 and 131.6) where the mainstem was found to be dry. Reaches throughout the length of the river had calculated gains or losses that were less than the sum of measurement errors for the respective reaches of river.

Scientific Investigations Report↗
USGS2005

Simulation of flow and sediment transport in the white sturgeon spawning habitat of the Kootenai River near Bonners Ferry, Idaho

Characterization of sediment transport of the Kootenai River in the white sturgeon spawning reach is needed by the Kootenai River White Sturgeon Recovery Team to predict sediment-transport conditions that improve spawning conditions for the white sturgeon (Acipenser transmontanus) in the Kootenai River near Bonners Ferry, Idaho. The decreasing population and spawning failure of the white sturgeon has led to much concern. Few wild juvenile sturgeon are found in the river today. The Kootenai River begins in British Columbia, Canada, and flows through Montana, Idaho, and back into British Columbia. A 15-mile reach of the Kootenai River in Idaho was studied, including the white sturgeon spawning reach that has been designated as a critical habitat near Bonners Ferry, Idaho, and a 1-mile long side channel around the western side of Shorty Island. A one-dimensional sediment-transport model of the study reach was developed, calibrated, and used to simulate the response of the hydraulic and sediment system to varying discharges and water-surface elevations. The model comprises 79 cross sections, most of which came from a previous river survey conducted in 2002-03. Bed-sediment samples collected in 2002 and additional samples collected for this study in 2004 were used in the model. The model was calibrated to discharge and water-surface elevations at two U.S. Geological Survey gaging stations. The model also was calibrated to suspended-sediment discharge at several sites in the study reach. The calibrated model was used to simulate six different management alternatives to assess erosion and deposition under varying hydraulic conditions at the end of 21 days of simulation. Alternative 1 was simulated with a discharge of 6,000 cubic feet per second (ft3/s), alternative 2 with 20,000 ft3/s, alternative 3 with 40,000 ft3/s, and alternatives 4 through 6 with 60,000 ft3/s and represents low to high discharges in the river since the construction of Libby Dam. Sediment deposition was dominant in management alternatives 1 through 4. The streambed in the sandbed reach changed little or not at all. The gravel-cobble reach was more dynamic. In alternatives 1 through 4, deposition was the dominant feature because increasing river discharge alone did not produce boundary shear stresses that can erode and transport streambed sediments. Water-surface slope probably was the limiting factor in these alternatives because backwater conditions flattens the stage throughout the reach. High flows in the river probably would be more effective in eroding the streambed and transporting sediments if water-surface slope was increased. One practical method for increasing the slope is to lower the water level in Kootenay Lake. Two additional alternatives (5 and 6) were simulated to demonstrate the effects of a steeper slope in the study reach. Simulation results from management alternatives 5 and 6 (a discharge of 60,000 ft3/s) were quite different than those from alternatives 1-4. Erosion was the dominant feature in these simulations because water-surface slopes were increased by lowering water levels in Kootenay Lake. Slopes in alternatives 5 and 6 were 2.4 and 3.5 times, respectively, greater than slope in alternative 4. For alternatives 5 and 6, sediment deposition dominated in the gravel-cobble reach while erosion dominated in the sandbed reach. Downstream of Ambush Rock (river mile 151.8) in the sandbed reach, maximum streambed decreased 2 and 3 feet in alternatives 5 and 6, respectively. Decreases also were prevalent in the side channel and averaged 1 foot or greater. White sturgeon eggs have been collected in the study reach since 1994. The largest number of eggs have been collected in the reach adjacent to Shorty Island. Another large number of eggs was located between river miles 149 and 146. Although these reaches for alternatives 5 and 6 were erosional, these reaches are still considered unsuitable spawning habitat because

Scientific Investigations Report↗