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At least 1,135 records · Page 63Linked to original sources

Generalized sediment budgets of the Lower Missouri River, 1968–2014

Sediment budgets of the Lower Missouri River were developed in a study led by the U.S. Geological Survey in cooperation with the U.S. Army Corps of Engineers. The scope of the study included the development of a long-term (post-impoundment, 1968–2014) average annual sediment budget and selected annual, monthly, and daily sediment budgets for a reach and period that adequate data were available. Included in the analyses were 31 main-stem and tributary stations of the Lower Missouri River and two Mississippi River stations—the Mississippi River below Grafton, Illinois, and the Mississippi River at St. Louis, Missouri. Long-term average annual suspended-sediment loads of Missouri River main-stem stations ranged from 0.33 million tons at the Missouri River at Yankton, South Dakota, station to 71.2 million tons at Missouri River at Hermann, Mo., station. Gaged tributary gains accounted for 9–36 percent of the local reach budgets and cumulative gaged tributary contributions accounted for 84 percent of the long-term average suspended-sediment load of the Missouri River at Hermann, Mo., station. Although the sediment budgets for seven defined main-stem reaches generally were incomplete—missing bedload, reach storage, and ungaged tributary contributions—the budget residuals (net result of sediment inputs and outputs) for six of the seven reaches ranged from -7.0 to 1.7 million tons, or from -9.2 to 4.0 percent of the reach output suspended-sediment load, and were within the 10 percent reported measurement error of annual suspended-sediment loads for large rivers. The remaining reach, downstream from Gavin’s Point Dam, extended from Yankton, S. Dak., to Sioux City, Iowa, and had a budget residual of -9.8 million tons, which was -88 percent of the suspended-sediment load at Sioux City. The Lower Missouri River reach from Omaha, Nebraska, to Nebraska City, Nebr., had periods of concurrent sediment data for each primary budget component with which to analyze and determine a suspended-sediment budget for selected annual, monthly, and daily time increments. The temporal changes in the cumulative annual budget residuals were poorly correlated with the comparatively steady 1968–2011 annual stage trends at the Missouri River at Nebraska City, Nebr., station. An accurate total sediment budget is developed by having concurrent data available for all primary suspended and bedload components for a reach of interest throughout a period. Such a complete budget, with concurrent record for suspended-sediment load and bedload components, is unavailable for any reach and period in the Lower Missouri River. The primary data gaps are in bedload data, and also in suspended-sediment gains and losses including ungaged tributary inputs and sediment storage. Bedload data gaps in the Missouri River Basin are much more prevalent than suspended-sediment data gaps, and the first step in the development of reach bedload budgets is the establishment of a standardized bedload monitoring program at main-stem stations. The temporal changes in flow-adjusted suspended-sediment concentrations analyzed at main-stem Missouri River stations indicated an overall downward change in concentrations between 1968 and 2014. Temporary declines in flow-adjusted suspended-sediment concentrations during and following large floods were evident but generally returned to near pre-flood values within about 6 months. Data uncertainties associated with the development of a sediment budget include uncertainties associated with the collection of suspended-sediment and bedload data and the computation of suspended-sediment loads. These uncertainties vary depending on the frequency of data collection, the variability of conditions being represented by the discrete samples, and the statistical approach to suspended-sediment load computations. The coefficients of variation of suspended-sediment loads of Missouri River tributary stations for 1968–2014 were greater, 75.0 percent, than the main-stem stations, 47.1 percent. The lower coefficient of variation at main-stem stations compared to tributaries, primarily is the result of the lower variability in streamflow and sediment discharge identified at main-stem stations. To obtain similar accuracy between suspended-sediment loads at main-stem and tributary stations, a longer period of record is required of the tributary stations. During 1968–2014, however, the Missouri River main-stem station record was much more complete (87 percent) than the tributary station record (28 percent).

Missouri River Basin↗

Water-quality conditions with an emphasis on cyanobacteria and associated toxins and taste-and-odor compounds in the Kansas River, Kansas, July 2012 through September 2016

Cyanobacteria cause a multitude of water-quality concerns, including the potential to produce toxins and taste-and-odor compounds that may cause substantial economic and public health concerns, and are of particular interest in lakes, reservoirs, and rivers that are used for drinking-water supply. Extensive cyanobacterial blooms typically do not develop in the Kansas River; however, reservoirs in the lower Kansas River Basin occasionally develop blooms that may affect downstream water quality. During July 2012 through September 2016, continuous and (or) discrete water-quality data were collected at several sites (Wamego, De Soto, and three main reservoir-fed tributaries) on the Kansas River to characterize the sources, frequency and magnitude of occurrence, and causes of cyanobacteria, cyanobacterial toxins, and taste-and-odor compounds and to develop a real-time notification system of changing water-quality conditions that may affect drinking-water treatment. Algal biomass, as estimated by chlorophyll, was consistently higher at the downstream De Soto site than the upstream Wamego site. Higher algal biomass at the De Soto site likely was caused by algal growth during downstream transport without major losses due to grazing by aquatic organisms or other processes. Algal biomass at the Wamego and De Soto sites was negatively correlated with streamflow and total and bioavailable nutrient concentrations. The negative association between algal biomass and nutrients in the Kansas River likely reflects the relatively strong positive association between nutrient concentrations and streamflows. Cyanobacteria were relatively common in the Kansas River but rarely dominated the algal community. Like overall algal biomass, cyanobacterial abundances typically were higher at the De Soto site than the Wamego site. Cyanobacterial abundances generally peaked in late summer or early fall (July through October), with smaller peaks occasionally observed in spring (April through May). Cyanobacteria in the Kansas River rarely exceeded 20,000 cells per milliliter, the abundance at which cyanobacteria may become a concern for drinking-water treatment. Relations between cyanobacterial abundance and streamflow, turbidity, and nutrients in the Kansas River were similar to those between chlorophyll and total phytoplankton abundance, indicating the same processes that influence overall algal biomass and dynamics also are influencing cyanobacteria. The cyanotoxin microcystin was detected in about 27 percent of the samples collected from Kansas River tributary and main-stem sites. Cylindrospermopsin was detected in one sample from the De Soto site. Microcystin occurrence and concentration were similar between the Wamego and De Soto sites. Concentrations exceeded the U.S. Environmental Protection Agency health advisory guidance values for finished drinking water of 0.3 (for bottle-fed infants and pre-school children) and 1.6 micrograms per liter (μg/L; for school-age children and adults) in 6 percent or less of samples collected. These guidance values are for finished drinking water and are not directly applicable to observed environmental concentrations but do provide a benchmark for comparison. Microcystin was detected most often and had the highest concentrations during summer. Though seasonal patterns in microcystin occurrence were generally consistent, seasonal maxima varied by an order of magnitude across years. The taste-and-odor compounds geosmin and 2-methylisoborneol (MIB) were detected in about 78 and 43 percent of samples, respectively, collected across all sites (main stem and tributaries). Geosmin and MIB occurrence and concentration varied considerably between the Wamego and De Soto sites. Geosmin was detected in about 67 percent of Wamego samples and 81 percent of De Soto samples. The human detection threshold of 5 nanograms per liter (ng/L) was exceeded for geosmin in about 11 and 17 percent of the samples collected at the Wamego and De Soto sites, respectively. Geosmin was detected during all months of the year at both sites, and there were no clear seasonal patterns. MIB was detected less frequently in the Kansas River than geosmin and was observed in about 42 percent of Wamego samples and 33 percent of De Soto samples. Concentrations exceeded 5 ng/L in about 7 and 5 percent of samples from the Wamego and De Soto sites, respectively. As observed for geosmin, there were no clear seasonal patterns in MIB occurrence or concentration. There seems to be a connection between microcystin detections in the Kansas River and occurrence of microcystin in upstream reservoirs (and tributary streams). Microcystin concentrations greater than 0.3 μg/L may be likely during the summer when streamflow is less than 3,000 cubic feet per second (ft 3 /s) and contributions from Milford Lake exceed about 30 percent of total flow in the Kansas River. Observed microcystin concentrations typically were higher at the De Soto site than the Wamego or tributary sites during 2012 through 2016, indicating cyanobacteria may continue to grow and produce microcystin once introduced to the Kansas River. The spatial and temporal patterns in geosmin and MIB occurrence and concentration were more complex than microcystin. There were no clear connections between geosmin and MIB occurrence in the Kansas River and potential upstream reservoir (or tributary stream) sources. Likewise, there was not a clear relation between algal biomass, cyanobacteria, or actinomycetes bacteria and taste-and-odor events in the Kansas River. Geosmin and MIB were not strongly correlated with any measured environmental variable at either Kansas River site. Continuous water-quality data may be used independently or in combination with regression models to provide information on changing water-quality conditions that may affect drinking-water treatment processes or recreational activities on the Kansas River. For example, logistic regression model outputs and continuous water-quality data may both be indicative of the potential for microcystin events. Logistic regression models that are estimating a high probability of microcystin occurrence at concentrations above 0.1 μg/L can be used as one indicator. Streamflows less than 3,000 ft 3 /s during upstream reservoir releases during periods with low turbidity and increased chlorophyll fluorescence, specific conductance, and pH values may also be indicative of microcystin events. Advanced or near-real-time notification may inform proactive, rather than reactive, management strategies when water-quality conditions are changing rapidly or are likely to cause cyanobacteria-related events.

Kansas↗

Precipitation, temperature, groundwater-level elevation, streamflow, and potential flood storage trends within the Brazos, Colorado, Big Cypress, Guadalupe, Neches, Sulphur, and Trinity River basins in Texas through 2017

The U.S. Geological Survey (USGS), in cooperation with the U.S. Army Corps of Engineers (USACE), analyzed streamflow trends and streamflow-related variables through 2017 in seven important water-supply basins to provide information that can help water managers with the USACE and river authorities make future water management decisions. The primary purpose of this report is to document trends in long-term streamflow data at 114 selected USGS streamflow-gaging stations and 36 simulated reservoir-inflow stations in 7 river basins primarily in Texas: Brazos, Colorado, Big Cypress, Guadalupe, Neches, Sulphur, and Trinity. In this report, trends were considered statistically significant if their p -values were less than or equal to 0.05 ( p -value ≤0.05). Streamflow data selected for temporal trend analyses included annual minimum streamflow, annual peak streamflow, and streamflow volume. Precipitation, air temperature, and groundwater-level-elevation data were analyzed for trends that may help to explain changes observed in the streamflow statistics. Basins were divided into sections along county lines for precipitation analyses. Streamflow volumes were analyzed for associations with potential flood storage. The potential flood storage, defined as the difference between maximum storage and normal storage, was computed for each dam from the National Inventory of Dams database and accumulated over time based on the completion date of the dam. Precipitation and air temperature trends were analyzed for each of the eight climate divisions (High Plains, Trans-Pecos, Low Rolling Hills, Edwards Plateau, North Central Texas, South Central Texas, East Texas, and Upper Coast). Results of precipitation trend analyses indicated moderate upward trends in the Upper Coast and East Texas Climate Divisions analyzed on an annual time step from 1900 through 2017. These two climate divisions are in the eastern and southeastern parts of the State, and they receive more mean annual precipitation (45.88 and 46.09 inches, respectively) than the other climate divisions. The results of air temperature analyses indicated upward trends in annual mean air temperature within all climate divisions, with a mean slope of 0.02 degree Fahrenheit per year, or 1 degree every 50 years. Within the Brazos River Basin, results of precipitation trend analyses on an annual time step indicated that precipitation amounts are most likely increasing in the lower and middle sections of the basin. Downward trends in annual streamflow and in the ratio of streamflow volume to precipitation volume were indicated at 7 of the 15 stations in the upper sections of the basin. The lower sections of the basin had mostly downward trends in annual minimum streamflow, whereas upward trends in annual minimum streamflow were indicated in the upper sections of the basin. Downward trends in annual peak streamflow were indicated at many of the stations in the upper sections of the basin. At the same seven stations in the upper sections of the basin where there were downward trends in annual streamflow, there were also downward trends in the ratio of streamflow volume to precipitation volume. The data from the same seven stations indicated negative associations between potential flood storage volume and annual streamflow volume and downward trends in the ratio of annual streamflow volume to potential flood storage volume. With the known addition of 13,006,394 acre-feet of potential flood storage between 1900 and 2010 in the subbasins analyzed, streamflow volumes have decreased in the upper sections of the Brazos River Basin. Within the Colorado River Basin, results of precipitation trend analyses on an annual time step indicated no trends in the basin. Downward trends in annual streamflow were indicated at 16 stations in the upper sections of the basin, whereas no trends in annual streamflow were indicated in the lower section of the basin. In the lower section of the basin, one station that was operated as a continuous streamflow-gaging station through 2017 had a downward trend in annual minimum streamflow, and another station (operated through 2007) had an upward trend in annual minimum streamflow. In the upper sections of the basin, data from seven stations indicated upward trends in annual minimum streamflow, and data from six stations indicated downward trends. Data from 18 stations in the upper sections of the basin indicated downward trends in annual peak streamflow. Thirteen of the 16 stations in the upper sections of the basin with data that indicated downward trends in annual streamflow also have data that indicated downward trends in the ratio of streamflow volume to precipitation volume. Data from the same 13 stations indicated negative associations between potential flood storage volume and annual streamflow volume and downward trends in the ratio of annual streamflow volume to potential flood storage volume. With the known addition of 7,193,147 acre-feet of potential flood storage between 1891 and 2014 in the subbasins analyzed, streamflow volumes have decreased in the upper sections of the Colorado River Basin. Within the Big Cypress Basin, results of precipitation trend analyses on annual, seasonal, and monthly time steps indicated almost no trends in the basin as defined in this report. However, the annual precipitation p -value only slightly exceeded the p -value threshold for a statistically significant trend. Given the upward trend in precipitation in the East Texas Climate Division, which includes the Big Cypress Basin, and the low p -value for annual precipitation within the basin, precipitation in the basin may be increasing over time. Two annual streamflow trends, one upward and one downward, were in the upper parts of the basin. Data from USGS streamflow-gaging station 07346000 Big Cypress Bayou near Jefferson, Texas, indicated an upward trend in annual minimum streamflow and a downward trend in annual peak streamflow. The station is immediately downstream from Lake O’ the Pines; presumably, minimums have increased because of regulated releases, and annual peaks have decreased because of storage from the lake for flood control. Despite the known addition of 2,737,154 acre-feet of potential flood storage between 1898 and 2011 in the subbasins analyzed, there have not been widespread reductions in streamflow volumes in the Big Cypress Basin, except for within the drainage area for the farthest upstream station on the main stem downstream from Mount Pleasant, Texas. Within the Guadalupe River Basin, results of precipitation trend analyses on an annual time step indicated an upward trend in the lower section of the basin, but no trends in annual streamflow were indicated in the lower section of the basin. In the upper section of the basin, data from 1 of the 13 stations indicated an upward trend in annual streamflow. Data from 6 of the 13 stations in the upper section of the basin indicated a trend in annual minimum streamflow with 4 upward and 2 downward trends. Data from 2 of the 13 stations in the upper section of the basin indicated downward trends in annual peak streamflow. Despite the known addition of 2,016,534 acre-feet of potential flood storage between 1849 and 2013 in the subbasins analyzed, streamflow volumes have not decreased in the Guadalupe River Basin. Within the Neches River Basin, results of precipitation trend analyses on an annual time step indicated upward trends in the basin. None of the data from stations analyzed in the Neches River Basin indicated annual trends in streamflow despite upward trends in annual precipitation within the basin. Data from 9 of the 19 stations analyzed in the basin indicated upward trends in annual minimum streamflow. Data from one of the simulated-inflow stations indicated a downward trend in annual minimum streamflow into Sam Rayburn Reservoir. Data from two stations indicated downward trends in annual peak streamflow, and data from one small subbasin indicated an upward trend in annual peak streamflow. Despite the known addition of 4,839,609 acre-feet of potential flood storage between 1888 and 2008 in the subbasins analyzed, there have not been widespread reductions in streamflow volumes in the Neches River Basin. Within the Sulphur River Basin, results of precipitation trend analyses on an annual time step indicated a moderate upward trend within the basin. Data from only one of the stations, the simulated inflow to Jim Chapman Lake, indicated an annual upward trend in streamflow despite an upward trend in annual precipitation throughout the basin. Data from three of the six stations in the Sulphur River Basin indicated upward trends in annual minimum streamflow, and data from one of the six stations indicated a downward trend in annual peak streamflow. Despite the known addition of 6,933,361 acre-feet of potential flood storage between 1904 and 2006 in the subbasins analyzed, streamflow volumes have not decreased in the Sulphur River Basin. Within the Trinity River Basin, results of precipitation trend analyses on an annual time step indicated upward trends in most sections of the basin. Data from 8 of the 36 stations analyzed for trends in annual streamflow indicated upward trends, and all 8 stations are in the upper sections of the basin. None of the data from stations in the lower sections of the basin indicated trends in annual streamflow. Data from 16 of the 36 stations indicated upward trends in annual minimum streamflow. Upward trends in annual minimum streamflow could be the result of managed reservoir releases in combination with wastewater treatment plant releases in the large Dallas-Fort Worth metroplex in the upper sections of the basin. All the trends in annual peak streamflow were in the sections of the basin that include the Dallas-Fort Worth metroplex. Data from two stations, one USGS streamflow-gaging station and one simulated-inflow station, indicated upward trends in annual peak streamflow, and data from one streamflow-gaging station indicated a downward trend in annual peak streamflow. Of the basins included in this study, the Trinity River Basin has the second largest amount of potential flood storage of 8,947,349 acre-feet from dams added between 1890 and 2013. Eleven stations in the Trinity River Basin had positive associations between potential flood storage volume and annual streamflow volume, indicating that annual streamflow increases as potential flood storage increases. Data from 7 of the 11 stations also indicated upward trends in annual streamflow. The positive associations may be the result of increases in minimum streamflow, which could be the result of any combination of managed reservoir releases, wastewater treatment plant releases, or increased runoff from urbanized areas, particularly in the urbanized area of the Dallas-Fort Worth metroplex.

Texas↗

Cimarron River alluvial aquifer hydrogeologic framework, water budget, and implications for future water availability in the Pawnee Nation Tribal jurisdictional area, Payne County, Oklahoma, 2016–18

The Cimarron River is a free-flowing river and is a major source of water as it flows across Oklahoma. Increased demand for water resources within the Cimarron River alluvial aquifer in north-central Oklahoma (primarily in Payne County) has led to increases in groundwater withdrawals for agriculture, public, irrigation, industrial, and domestic supply purposes. The Pawnee Nation of Oklahoma (Pawnee Nation) is particularly concerned about the sustainability of the Cimarron River alluvial aquifer and whether the aquifer will continue to be a viable water resource for future generations of Tribal members and residents. To better understand current (2021) water resources and possible future water availability in the Pawnee Nation Tribal jurisdictional area, the U.S. Geological Survey, in cooperation with the Bureau of Indian Affairs and the Pawnee Nation of Oklahoma, compiled available hydrogeologic data and developed conceptual and numerical groundwater-flow models for the Cimarron River alluvial aquifer in Payne County, north-central Oklahoma, including a focus area in the Pawnee Nation Tribal jurisdictional area for the 2016–18 study period. A conceptual water budget was created to establish estimates of groundwater fluxes into and out of the aquifer through hydrologic boundaries and groundwater withdrawals for use in the numerical groundwater-flow model. The conceptual water budget focuses on the alluvial aquifer, meaning that inflows include sources of water to the aquifer and that outflows include sources of water out of the aquifer, such as base-flow contributions to the Cimarron River. The conceptual water budget was constructed by using data from 2017 (the most complete year of record for each data type included in the model) for the Pawnee Nation subdomain of the Cimarron River alluvial aquifer model extent (Pawnee Nation subdomain). Groundwater withdrawals were estimated from groundwater-withdrawal rate information for permanent and temporary permitted wells that was obtained from the Oklahoma Water Resources Board. One-half of each annual permitted groundwater-withdrawal rate allotted was used as the estimated annual groundwater-withdrawal amount. Halving the permitted groundwater-withdrawal rate was done because permitted withdrawal rates are the maximum permitted rate and actual groundwater withdrawals are generally appreciably lower than the maximum permitted rate. Total groundwater withdrawals were estimated as 1,300 acre-feet per year for the Pawnee Nation subdomain. Various hydrogeologic data were measured to assist with model development, including depth to bedrock and water-table altitude data. In support of the model development, analyses pertaining to groundwater flow, groundwater/surface-water interactions, base flows in the Cimarron River, and lithological interpretations in the Pawnee Nation Tribal jurisdictional area were used to compute a conceptual water budget applicable to the 2016–18 study period. A numerical groundwater-flow model was developed using the hydrogeologic framework of the Cimarron River alluvial aquifer and the conceptual water budget. The numerical model consists of a single layer representing alluvium and terrace deposits within the alluvial aquifer model area. Hydraulic conductivities were estimated and modeled for the alluvium and terrace deposits in the alluvial aquifer. Base-flow values were estimated using the base-flow index from streamflow data collected at U.S. Geological Survey streamgages. Stream seepage values were derived from the mean 2017 base-flow index between certain streamgages. Hydraulic conductivities were specified an initial (before calibration) value of 120 feet per day for the alluvium deposits and 16 feet per day for the terrace deposits. The simulated inflows in the numerical groundwater-flow model of the Pawnee Nation subdomain were higher than the inflows of conceptual water budget, and the simulated outflows were lower than the outflows of the conceptual water budget. Overall, simulated base flows matched closely to observed base flows for the 2016 and 2017 stress periods. Simulated streamflow tended to match better with the observed streamflow for 2017, which was the period with the most data for the Cimarron River alluvial aquifer model. Streamflow capture analysis was applied to the steady-state simulation to identify areas of the aquifer where base flows in the Cimarron River were most sensitive to groundwater withdrawals. The initial base-flow value was assigned the value obtained from streamflow-routing software used to simulate stream outflow for the calibrated steady-state base model. Subsequent simulations were run in each active cell in the Pawnee Nation subdomain for a specified groundwater-withdrawal rate of 180,000 cubic feet per day. The study area that includes the Pawnee Nation subdomain is in the upper Arkansas River Basin. A groundwater-withdrawal rate of 180,000 cubic feet per second per day represents a 34 percent increase compared to the highest permitted groundwater-withdrawal rate for the study area, which corresponds to the estimated 34 percent increase in groundwater withdrawals predicted by 2060 for the upper Arkansas River Basin. Simulated streamflow capture was highest in the alluvium deposits adjacent to the Cimarron River; that is, base flow in the Cimarron River decreased the most for simulated groundwater withdrawals in the alluvium deposits adjacent to the Cimarron River. Streamflow capture increased as the distance of a well from the Cimarron River decreased in the simulation. The northeastern part of the Pawnee Nation subdomain showed greater streamflow capture in a broader area; streamflow in that part of the Pawnee Nation subdomain is likely more sensitive to groundwater withdrawals compared to other parts of the Pawnee Nation subdomain.

Oklahoma↗

Evaluation of salinity and nutrient conditions in the Heart River Basin, North Dakota, 1970–2020

The Heart River Basin is predominantly an agricultural basin in western North Dakota and is approximately 3,350 square miles. The U.S. Geological Survey, in cooperation with the U.S. Department of Agriculture Natural Resources Conservation Service and the Grant County Soil Conservation District, completed a study to assess spatial and temporal patterns of water quality in the Heart River Basin. The purpose of this report is to describe the methods and results of a study to evaluate salinity and nutrients in the Heart River Basin in western North Dakota. Water-quality and streamflow data used in the study were compiled from 1970 to 2020 using the National Water Quality Monitoring Council Water Quality Portal and National Water Information System. Changes in streamflow characteristics were investigated at three sites from 1970 to 2020, and changes in water quality were investigated at four sites from 1974 to 2019. Streamflow analysis indicated decreasing streamflow from 1970 until the late 1990s followed by increasing streamflow through 2020, with the largest increase in the 7-day minimum streamflow or base flow. For the historical water-quality trend period (1974–2019), total dissolved solids, sulfate, sodium, chloride, and sodium adsorption ratio concentrations have increased since the mid-1970s through 2019. Potassium concentrations during the historical period remained mostly constant with some small fluctuations. Calcium and magnesium concentrations increased since the mid-1970s at all sites, except for a decrease at one site between 1974 and 1999. During the recent trend period (1999–2019), increasing concentrations in total dissolved solids, sulfate, sodium, chloride, calcium, magnesium, and sodium adsorption ratios were observed across the Heart River Basin. The magnitude of the increases was smaller at tributary sites compared to main-stem sites. During the recent period, potassium was mostly constant, although small (−0.9 milligram per liter or less) decreases on tributaries and minor (1.3 milligrams per liter) increases on the main-stem sites were detected. Unlike dissolved ion concentrations, significant increases in nutrient concentrations were not detected from 1999 to 2019, but nitrate plus nitrite concentrations most likely decreased upstream from Lake Tschida. Inverse modeling for period 1 (1974–99) in model zone 1 (Heart River reach from site 5 to site 6) had eight reasonable models that indicated the clay mineral-water interactions and dissolution of evaporites control the geochemistry. Results of the inverse modeling for period 2 (1999–2019) in model zone 1 also had eight reasonable models that indicated that the dissolution of evaporites was the major geochemical control. Results of the geochemical modeling for period 1 (1974–99) in model zone 2 (Heart River and Sweetbriar Creek reach from sites 20 and 21 to site 22) produced seven reasonable models, and the geochemical control of the system was the dissolution of sulfate evaporite minerals. Geochemical modeling results for period 2 (1999–2019) in model zone 2 produced 11 reasonable models and was also controlled by the dissolution of sulfate evaporite minerals. Differences between the two model zones indicated that geology controls some of the water-quality changes in the Heart River Basin. Loads were estimated for total dissolved solids, sulfate, sodium, and chloride and total phosphorus. Annual loads estimated for the Heart River from 2013 through 2020 at the Heart River site upstream from Lake Tschida (site 5) and near Mandan (site 22) were generally greatest in 2014 and least in 2016 for total dissolved solids, sulfate, sodium, and chloride. Most of the annual loads of total dissolved solids, sulfate, sodium, and chloride are delivered in March through July in the Heart River at these sites and are likely from snowmelt and spring and summer rains. The mean annual yields of total dissolved solids and sodium from 2013 to 2020 generally were largest in Big Muddy Creek (site 18), whereas yields of sulfate and chloride were largest at Sweetbriar Creek (site 21) compared to the other selected sites in the Heart River Basin. Larger yields of total dissolved solids, sulfate, sodium, and chloride at sites located on Big Muddy Creek and Sweet Briar Creek in the lower Heart River Basin were likely a result of differences in geology and soils upstream from the selected sites. A mass balance of total dissolved solids, sulfate, sodium, and chloride was estimated for the lower Heart River Basin, specifically the reach below Lake Tschida to Mandan (site 7 to site 22). Intervening flow was the largest contributor to the dissolved ion loads in the lower Heart River Basin and is an important part of understanding the transport of dissolved ions in the basin. The intervening load can include groundwater discharge, irrigation return flow, local runoff, and input from smaller ephemeral tributaries. Tributaries in the lower Heart River Basin contributed portions of the total dissolved solids, sulfate, sodium, and chloride loads at the Heart River near Mandan (site 22) that generally were proportional to the streamflow contributions. Annual loads for total phosphorus between 2013 and 2020 at the Heart River site upstream from Lake Tschida (site 5) and near Mandan (site 22) generally were largest in 2019 and smallest in 2016. Most of the total phosphorus loads for main-stem sites 5 and 22 were transported in March, April, and June, likely from snowmelt and early summer rains. The mean annual yields of total phosphorus for 2013–20 were largest on the main-stem site upstream from Lake Tschida (site 5) and Sweetbriar Creek (site 21), whereas the smallest yields were in Big Muddy Creek (site 18). Much of the phosphorus that enters Lake Tschida from the upper basin does not get transported downstream to the lower basin, and much of the phosphorus in the lower basin was attributed to intervening flow.

North Dakota↗

Characterization of streamflow and nutrient occurrence in the upper White River Basin, Colorado, 1980–2020

In 2016, Colorado Parks and Wildlife identified filamentous algae collected from the main stem White River as Cladophora glomerata , a pervasive nuisance aquatic alga. Excessive levels of filamentous algae can compromise aesthetic quality, limit recreational activities, and have negative effects on aquatic life including strong fluctuations in dissolved oxygen levels and a reduction in overall biodiversity. To increase understanding of the biology of the upper White River Basin in Colorado, identify potential factors promoting or limiting nuisance algal abundance, and outline information to aid in the understanding and protection of water resources, the U.S. Geological Survey (USGS), in cooperation with the White River and Douglas Creek Conservation Districts and the White River Algae Technical Advisory Group, initiated a study to collect and analyze physical, chemical, and biological information for the upper White River Basin. The report describes long-term changes and spatial variations in streamflow and nutrient concentrations and loads in the upper White River Basin and identifies possible nutrient sources in the basin. Long-term streamflow and nutrient data indicate that conditions in the upper White River Basin have become more favorable to benthic algae over varying timescales. Upward trends in total phosphorus concentrations and loads were found at three sites across the basin from 2000 to 2020. Total phosphorus loads increased around 50 percent, ranging from 18 to 48 pounds per year. Annual estimated concentrations of total phosphorus from 2005 to 2020 were above algal-specific nutrient criteria at the North Fork White River at Buford, Colo., indicating that phosphorus concentrations at this site likely promote algal growth. Discrete concentrations of total phosphorus exceeded algal-specific nutrient criteria on the South Fork and main stem White River during the summer season, though less frequently than samples collected from the North Fork White River. Nitrogen to phosphorus molar ratios collected from July to September indicate movement from colimitation (10–22) to nitrogen limited (less than 13) conditions at the North Fork White River at Buford, Colo. and the South Fork White River at Buford, Colo. starting in 2012. The magnitude of trends in phosphorus loads were generally greater than trends in concentrations across all sites, indicating that the largest changes in concentrations occurred during greater streamflow periods. At White River above Coal Creek, near Meeker, Colo., significant downward trends in streamflow were found in August and September for mean streamflow (15 and 14 percent per decade, respectively) and 7-day minimum streamflows (23 and 22 percent per decade, respectively). Significant downward trends in annual 7-day minimum streamflows of 24 percent per decade, or 66 percent over the 40-year period of analysis, were also observed. Though not significant based on 90-percent confidence intervals, downward trends in 1-day maximum and mean streamflows in May and June and corresponding increases in April may indicate a shift toward earlier snowmelt runoff, as observed across western North America and the Colorado River Basin. Alteration of the annual hydrograph can influence factors that influence algae including nutrient input and dilution potential, water temperature, dissolved oxygen, light availability, and physical disturbance. Results from a synoptic-style sampling identified the lower North Fork White River subbasin as a large source of phosphorus to the downstream system. Large increases in phosphorus loads were observed below Marvine Creek. Synoptic samples and samples collected during spring and summer of 2019 and 2020 also show large increases in total nitrogen, orthophosphate, and total phosphorus occurring at the furthest three downstream sites on the White River. To further evaluate sources of nitrogen in the upper White River Basin, the dual isotopic composition of nitrate was compared across four sites. The isotopic compositions of nitrate were all within the expected range of typical soil-derived nitrate, though the same values can also be derived from a mixture of agricultural fertilizer and manure or septic sources.

Colorado↗

Assessment of channel morphology, hydraulics, and bedload transport along the Siletz River, western Oregon

Significant Findings Chinook salmon ( Oncorhynchus tshawytscha ) and Pacific lamprey ( Entosphenus tridentatus ) are native, anadromous fish species in the Siletz River Basin, western Oregon, that face many threats to their survival in freshwater and the ocean. The Confederated Tribes of Siletz Indians of Oregon seek to mitigate freshwater threats to Chinook salmon and Pacific lamprey, where possible, with habitat conservation and restoration efforts. This study was conducted to assist the Confederated Tribes of Siletz Indians of Oregon in documenting and understanding the hydrogeomorphic processes shaping present-day habitat conditions and assessing future habitat implications for Chinook salmon and Pacific lamprey along the main-stem Siletz River. As such, this study focused on understanding geomorphic processes and patterns of channel change, including lateral and vertical adjustments in channel position and changes in bed-material sediment (sands, gravels, and cobbles that mantle the channel bed), which collectively determine overall patterns of channel morphology and fluvial habitats. Objective One was to evaluate lateral changes in channel position, vertical changes in bed elevation, and longitudinal patterns in bed-material particle size along the Siletz River using detailed channel maps developed from aerial photographs collected from 1939 to 2016, long-term records of stage and discharge collected by the U.S. Geological Survey (USGS) near the City of Siletz, and sediment particle size data. Objective Two was to assess hydraulic conditions using one- and two-dimensional hydraulic models and transport capacity of bed-material sediment using bedload transport models and sediment particle size data for a range of discharge conditions. Objective Three was to identify potential burrowing habitat for lamprey larvae (PBH) along the Siletz River network and provide insights in local factors influencing PBH along the main-stem Siletz River. The overall findings are synthesized to describe habitat implications for Chinook salmon and Pacific lamprey under present-day and future conditions. Results of Objective One, an evaluation of changes in channel position and bed elevations and longitudinal patterns in bed-material particle size along the Siletz River, include the following From 1939 to 2016, channel planform and the mapped area of gravel bars did not change considerably along the 97.2-kilometers (km) of Siletz River between Elk Creek and Millport Slough, except for in short sections generally less than 1 km long. This inherent lateral channel stability results from the resistant bedrock and terraces that bound most of the channel and limit lateral changes in channel position. Intermittent sections along the study reach where the active channel widened at channel bends displayed noticeable planform changes and increases in mapped bar area. From water year (WY; a 12-month period from October 1 through September 30 and named for the year in which it ends) 1906 to 2021, changes in the stage-discharge relation interpreted as rising and lowering channel bed levels were observed at the USGS streamgage 14305500 (Siletz River at Siletz, OR) in response to floods (such as high flows in February 1996 and January 2002 that exceeded 0.1 and 0.667 annual exceedance probabilities [AEP] events, respectively). However, the rating curve representing the stage-discharge relation did not change in response to high-magnitude floods between 2007 and 2021. Along the approximately 54-km of the Siletz River between Moonshine Park and the Bulls Bag area, surficial particle distributions varied considerably between sampling sites in response to changes in channel width and gradient, sediment inputs from tributaries, and basin geology. Despite this variability, median particle sizes tended to decrease in size in the downstream direction over the 54 km. Results of Objective Two, an evaluation of hydraulic and bedload transport conditions along the Siletz River, include the following The most substantial increases in maximum and mean water velocity and bedload sediment transport capacity occurred at events between the 0.995 and 0.50 AEPs. Events of these magnitudes occur approximately every 1–2 years. Smaller events (0.995 AEP) are generally contained by the banks of the main channel, whereas larger events (0.50 AEP) generally spill over the banks and inundate high-elevation bar and low-elevation floodplain surfaces. Multiple smaller floods within a WY that exceed the 0.995 and 0.50 AEPs (such as in WY 1996) can transport as much or more bed-material sediment than a single, higher magnitude event (such as the maximum event recorded in WY 2000 with an estimated AEP of around 0.002). Bedload transport capacity generally exceeds sediment supply (greater than 2 millimeters [mm]) for most of the study area from Wildcat Creek to the City of Siletz as evidenced by substantial in-channel bedrock. Despite overall conditions of limited sediment supply, transport capacity still varies considerably within and between years with discharge magnitude and spatially in relation to local hydraulics imposed by bedrock, channel morphology, and human infrastructure (such as bridges). Results of Objective Three, an analysis of PBH for lamprey larvae, include the following About 28 percent of the Siletz River network meets the mean annual suspended sediment loads and channel slope criteria for PBH. Along the main-stem Siletz River, in-channel bedrock outcrops and high transport capacity are expected to further constrain PBH. Together, these results suggest that most of the Siletz River between Wildcat Creek and the City of Siletz has had only modest vertical and lateral change between the 1930s and 2010s because of the bedrock in and along the main channel and the river’s relatively high transport capacity relative to bed-material sediment supply. However, localized sections of the Siletz River where the active channel widens, particularly at channel bends, exhibited some change in channel planform and the locations and area of gravel bars. In the future, moderate increases in autumn-winter discharge may not result in substantial changes in coarse gravel bars along the Siletz River but may result in selective transport of finer bed-material sediment (gravel, sands, and silts) that provide spawning habitats for Chinook salmon and Pacific lamprey and burrowing habitats for lamprey larvae. Assuming no substantial changes in bed-material sediment supply, increased bedload transport capacity may cause frequent entrainment of lamprey larvae that are burrowed in coarse sand deposits, suspension and downstream transport of salmon eggs incubating in gravels, and reductions in the areas of spawning gravels for Chinook salmon and Pacific lamprey. Exact implications of current and future discharge conditions for these species along the Siletz River depends on many factors, including sediment supply, local hydraulics, and the timing of flood events relative to fish life stages.

Oregon↗

Characterization and simulation of ground-water flow in the Kansas River Valley at Fort Riley, Kansas, 1990-98

Hydrologic data and a ground-water flow model were used to characterize ground-water flow in the Kansas River alluvial aquifer at Fort Riley in northeast Kansas. The ground-water flow model was developed as a tool to project ground-water flow and potential contaminant-transport paths in the alluvial aquifer on the basis of past hydrologic conditions. The model also was used to estimate historical and hypothetical ground-water flow paths with respect to a private- and several public-supply wells. The ground-water flow model area extends from the Smoky Hill and Republican Rivers downstream to about 2.5 miles downstream from the city of Ogden. The Kansas River Valley has low relief and, except for the area within the Fort Riley Military Reservation, is used primarily for crop production. Sedimentary deposits in the Kansas River Valley, formed after the ancestral Kansas River eroded into bedrock, primarily are alluvial sediment deposited by the river during Quaternary time. The alluvial sediment consists of as much as about 75 feet of poorly sorted, coarse-to-fine sand, silt, and clay, 55 feet of which can be saturated with ground water. The alluvial aquifer is unconfined and is bounded on the sides and bottom by Permian-age shale and limestone bedrock. Hydrologic data indicate that ground water in the Kansas River Valley generally flows in a downstream direction, but flow direction can be quite variable near the Kansas River due to changes in river stage. Ground-water-level changes caused by infiltration of precipitation are difficult to detect because they are masked by larger changes caused by fluctuation in Kansas River stage. Ratios of strontium isotopes Sr87 and Sr86 in water collected from wells in the Camp Funston Area indicate that the ground water along the northern valley wall originates, in part, from upland areas north of the river valley. Water from Threemile Creek, which flows out of the uplands north of the river valley, had Sr87:Sr86 ratios similar to those in ground water from wells in the northern Camp Funston Area. In addition, comparison of observed water levels from wells CF90-06, CF97-101, and CF97-401 in the Camp Funston Area and ground-water levels simulated for these wells using floodwave-response analysis indicates that ground-water inflow from bedrock is a hydraulic stress that, in addition to the changing stage in the Kansas River, acts on the aquifer. This hydraulic stress seems to be located near the northern valley wall because the effect of this stress is greater for well CF97-101, which is the well closest to the valley wall. Ground-water flow was simulated using a modular, three-dimensional, finite-difference ground-water flow model (MODFLOW). Particle tracking, used to visualize ground-water flow paths in the alluvial aquifer, was accomplished using MODPATH. Forward-in-time particle tracking indicated that, in general, particles released near the Kansas River followed much more variable paths than particles released near the valley wall. Although particle tracking does not simulate solute transport, this increased path variability indicates that, near the river, ground-water contaminants could follow many possible paths towards the river, whereas more distant from the river, ground-water contaminants likely would follow a narrower corridor. Particle tracks in the Camp Funston Area indicate that, for the 1990-98 simulation period, contaminants from the ground-water study sites in the Camp Funston Area would be unlikely to move into the vicinity of Ogden's supply wells. Backward-in-time particle tracking indicated that the flow-path and recharge areas for model cells corresponding to Ogden's supply wells lie near the northern valley wall and extend into the northern Camp Funston Area. The flow-path and recharge areas for model cells corresponding to Morris County Rural Water District wells lie within Clarks Creek Valley and probably extend outside the model area. Three hypothetical simulations, i

Water-Resources Investigations Report↗

Water quality in the Little Sac River basin near Springfield, Missouri, 1999-2001

The Little Sac River, north of Springfield, Missouri, flows through mainly agricultural and forest land. However, the quality of the river water is a concern because the river flows into Stockton Lake, which is a supplemental drinking water source for Springfield. Large bacterial densities and nutrient concentrations are primary concerns to the water quality of the river. A 29-river mile reach of the Little Sac River is on the 1998 list of waters of Missouri designated under section 303(d) of the Federal Clean Water Act because of fecal coliform densities larger than the Missouri Department of Natural Resources standard (hereinafter referred to as Missouri standard) of 200 colonies per 100 milliliters for whole-body contact recreation. During an investigation of the water quality in the Little Sac River by the U.S. Geological Survey, in cooperation with the Watershed Committee of the Ozarks, fecal coliform bacteria densities exceeded the Missouri standard (the standard applies from April 1 through October 31) in one sample from a site near Walnut Grove. At other sites on the Little Sac River, the Missouri standard was exceeded in two samples and equalled in one sample upstream from the Northwest Wastewater Treatment Plant (NW WTP) and in one sample immediately downstream from the NW WTP. Effluent from the NW WTP flows into the Little Sac River. Annually from April 1 through October 31, the effluent is disinfected to meet the Missouri standard for whole-body contact recreation. Fecal coliform bacteria densities in samples collected during this period generally were less than 100 colonies per 100 milliliters. For the rest of the year when the effluent was not disinfected, the bacteria densities in samples ranged from 50 (sample collected on November 1, 2000) to 10,100 colonies per 100 milliliters (both counts were non-ideal). When the effluent was disinfected and the fecal coliform bacteria density was small, samples from sites upstream and downstream from the NW WTP had a bacteria density larger than the density in the effluent. Other sources of bacteria are likely to be present in the study area in addition to the NW WTP. These potential sources include effluent from domestic septic systems and animal wastes. Nutrient concentrations in the Little Sac River immediately downstream from the NW WTP were affected by effluent from the NW WTP and possibly other sources. At two sites upstream from the NW WTP, median nitrite plus nitrate concentrations were 1.1 and 1.4 milligrams per liter. The median nitrite plus nitrate concentration for the effluent from the NW WTP was 6.4 milligrams per liter, and the median concentration decreased downstream in the Little Sac River to 2.2, 1.2, and 0.56 milligrams per liter. The effects of the effluent from the NW WTP on the water quality of the Little Sac River downstream from the NW WTP were reflected in an increase in discharge (effluent from the NW WTP can be as much as 50 percent of the flow at the site about 1.5 river miles downstream from the NW WTP), an increase in specific conductance values, an increase in several inorganic constituent concentrations, including calcium, magnesium, and sulfate, and a large increase in sodium and chloride concentrations. The effluent from the NW WTP seemed to have no effect on the pH value, temperature, and dissolved oxygen concentrations in the Little Sac River. Results of repetitive element polymerase chain reaction (rep-PCR) pattern analysis indicated that most Escherichia coli ( E. coli ) bacteria in water samples probably were from nonhuman sources, such as horses and cattle. The rep-PCR pattern analysis indicated that horses were an important source of E. coli downstream from the NW WTP, which was consistent with horses pastured adjacent to the sampling site. Fecal coliform bacteria loads increased upstream from the NW WTP from the most upstream site to the site immediately upstream from the NW WTP. Loads in the effluent from the NW WTP and also those in the Little Sac River downstream from the NW WTP were dependent on the treatment of the effluent. When the effluent was not disinfected, the loads in the effluent increased from those upstream. Downstream in the Little Sac River, the loads decreased, but then increased at the most downstream site. The increase may be a result of increased loads from tributaries and other sources not sampled during the study. When the effluent was disinfected, fecal coliform bacteria loads were less than loads in samples from the Little Sac River downstream from the NW WTP.

Water-Resources Investigations Report↗

Simulations of floodflows on the White River in the vicinity of U.S. Highway 79 near Clarendon, Arkansas

A two-dimensional finite-element surface-water model was used to study the effects of the proposed modification to the U.S. Highway 79 corridor on flooding on the White River near Clarendon, Arkansas. The effects of floodflows were simulated for the following scenarios: existing, natural, and four proposed bridging alternatives. All of the scenarios were modeled with floods having the 5- and 100-year recurrence intervals (115,100 and 216,000 cubic feet per second). The simulated existing conditions included a 3,200-foot White River bridge located on the east side of the study area near Clarendon, Arkansas; a 3,700-foot First Old River bridge located 0.5 mile west of the White River bridge opening; and a 1,430-foot Roc Roe Bayou bridge located 1.6 mile west of the First Old River bridge. The simulated hypothetical natural conditions involved removing the U.S. Highway 79 and the Union Pacific Railroad embankments along the entire length of the flood plain. The primary purpose of model simulations for natural conditions was to calculate backwater data for the existing and proposed conditions. The four simulated hypothetical proposed alternatives involved a 1.8-mile White River bridge located on the east side of the study area near Clarendon, Arkansas, either a 1,400-foot relief bridge (Alternative 1) or a 1,545 relief bridge (Alternatives 2-4) located 0.25 mile west of the White River bridge opening, and three different Roc Roe Bayou bridge openings ranging from 1,540-3,475 feet in length located 0.9 mile west of the relief bridge (Alternatives 1-4). Simulation of the 5-year floodflow for the existing bridge openings indicates that about 57 percent (65,600 cubic feet per second) of flow was conveyed by the White River bridge, about 26 percent (29,900 cubic feet per second) by the First Old River bridge, and about 17 percent (19,600 cubic feet per second) by the Roc Roe Bayou bridge. Maximum depth-averaged point velocities for the White River, First Old River, and Roc Roe Bayou bridges were 3.6, 1.6, and 3.3 feet per second, respectively. For the 100-year floodflow, the simulation indicates that about 56 percent (123,100 cubic feet per second) of flow was conveyed by the White River bridge, about 26 percent (56,200 cubic feet per second) by the First Old River bridge, and about 19 percent (41,000 cubic feet per second) by the Roc Roe Bayou bridge. The maximum depth-averaged point velocities for the White River, First Old River, and Roc Roe Bayou bridges were 4.2, 2.2, and 4.1 feet per second, respectively. Simulation of the 5-year floodflow for the proposed U.S. Highway 79 alignment alternatives indicates that 76-78 percent (87,100-89,900 cubic feet per second) of the flow was conveyed by the proposed White River bridge, 6-7 percent (7,000-7,500 cubic feet per second) by the proposed relief bridge, and 13-16 percent (14,600-18,600 cubic feet per second) by the proposed Roc Roe Bayou bridge. For the 100-year floodflow, simulations predicted that 70-72 percent (151,200-155,600 cubic feet per second) of the flow was conveyed by the proposed White River bridge, 9-10 percent (19,800-20,700 cubic feet per second) by the proposed relief bridge, and 14-20 percent (30,700-43,000 cubic feet per second) by the proposed Roc Roe Bayou bridge.

Water-Resources Investigations Report↗

Nitrogen and phosphorus in streams of the Great Miami River Basin, Ohio, 1998–2000

Sources and loads of nitrogen and phosphorus in streams of the Great Miami River Basin were evaluated as part of the National Water-Quality Assessment program. Water samples were collected by the U.S. Geological Survey from October 1998 through September 2000 (water years 1999 and 2000) at five locations in Ohio on a routine schedule and additionally during selected high streamflows. Stillwater River near Union, Great Miami River near Vandalia, and Mad River near Eagle City were selected to represent predominantly agricultural areas upstream from the Dayton metropolitan area. Holes Creek near Kettering is in the Dayton metropolitan area and was selected to represent an urban area in the Great Miami River Basin. Great Miami River at Hamilton is downstream from the Dayton and Hamilton-Middletown metropolitan areas and was selected to represent mixed agricultural and urban land uses of the Great Miami River Basin. Inputs of nitrogen and phosphorus to streams from point and nonpoint sources were estimated for the three agricultural basins and for the Great Miami River Basin as a whole. Nutrient inputs from point sources were computed from the facilities that discharge one-half million gallons or more per day into streams of the Great Miami River Basin. Nonpoint-source inputs estimated in this report are atmospheric deposition and commercial-fertilizer and manure applications. Loads of ammonia, nitrate, total nitrogen, orthophosphate, and total phosphorus from the five sites were computed with the ESTIMATOR program. The computations show nitrate to be the primary component of instream nitrogen loads, and particulate phosphorus to be the primary component of instream phosphorus loads. The Mad River contributed the smallest loads of total nitrogen and total phosphorus to the study area upstream from Dayton, whereas the Upper Great Miami River (upstream from Vandalia) contributed the largest loads of total nitrogen and total phosphorus to the Great Miami River Basin upstream from Dayton. An evaluation of monthly mean loads shows that nutrient loads were highest during winter 1999 and lowest during the drought of summer and autumn 1999. During the 1999 drought, point sources were the primary contributors of nitrogen and phosphorus loads to most of the study area. Nonpoint sources, however, were the primary contributors of nitrogen and phosphorus loads during months of high streamflow. Nonpoint sources were also the primary contributors of nitrogen loads to the Mad River during the 1999 drought, owing to unusually large amounts of ground-water discharge to the stream. The Stillwater River Basin had the highest nutrient yields in the study area during months of high streamflow; however, the Mad River Basin had the highest yields of all nutrients except ammonia during the months of the 1999 drought. The high wet-weather yields in the Stillwater River Basin were caused by agricultural runoff, whereas high yields in the Mad River Basin during drought resulted from the large, sustained contribution of ground water to streamflow throughout the year. In the basins upstream from Dayton, an estimated 19 to 25 percent of the nonpoint source of nitrogen and 4 to 5 percent of the nonpoint source of phosphorus that was deposited or applied to the land was transported into streams.

Ohio↗

Water quality of selected rivers in the New England Coastal Basins in Maine, Massachusetts, New Hampshire, and Rhode Island, 1998-2000

Nine rivers were monitored routinely for a variety of field conditions, dissolved ions, and nutrients during 1998-2000 as part of the New England Coastal Basins (NECB) study of the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) Program. The nine rivers, located primarily in the Boston metropolitan area, represented a gradient of increasing urbanization from 1 to 68 percent urban land use. Additional water samples were collected and analyzed for pesticides and volatile organic compounds at two of the nine rivers. Specific conductance data from all rivers were correlated with urban land use; specific conductance values increased during winter at some sites indicating the effect of road de-icing applications. In the more intensely urbanized basins, concentrations of sodium and chloride were high during winter and likely are attributed to road de-icing applications. Concentrations of total nitrogen and the various inorganic and organic nitrogen species were correlated with the percentage of urban land in the drainage basin. Total phosphorus concentrations also were correlated with urbanization in the drainage basin, but only for rivers draining less than 50 square miles. Preliminary U.S. Environmental Protection Agency total nitrogen and total phosphorus criteria for the rivers in the area were frequently exceeded at many of the rivers sampled. At the two sites monitored for pesticides and volatile organic compounds, the Aberjona and Charles Rivers near Boston, greater detection frequencies of pesticides were in samples from the spring and summer when pesticide usage was greatest. At both sites, herbicides were detected more commonly than insecticides. The herbicides prometon and atrazine and the insecticide diazinon were detected in over 50 percent of all samples collected from both rivers. No water samples contained pesticide concentrations exceeding any U.S. Environmental Protection Agency drinking-water standard or criteria for protecting freshwater aquatic life. The volatile organic compounds trichloroethylene, tetrachloroethylene, and cis-1,2- dichloroethylene--all solvents and de-greasers--were detected in all water samples from both rivers. The gasoline oxygenate methyl tert-butyl ether (MTBE) and the disinfection by-product chloroform were detected in all but one water sample from the two rivers. Two water samples from the Charles River had trichloroethylene concentrations that exceeded the U.S. Environmental Protection Agency Maximum Contaminant Level of 5 micrograms per liter for drinking water. Selected water-quality data from two NCEB rivers in the Boston metropolitan area were compared to two similarly sized intensely urban rivers in another NAWQA study area in the New York City metropolitan area and to other urban rivers sampled as part of the NAWQA Program nationally. Nutrient total nitrogen and total phosphorus concentrations and yields were less in the NECB study area than in the other study areas. In addition, the pesticides atrazine, carbaryl, diazinon, and prometon were detected less frequently and at lower concentrations in the two NECB rivers than in the New York City area streams or in the other urban NAWQA streams. Concentrations of the insecticides diazinon and carbaryl were detected more frequently and at higher concentrations in the NECB study area than in the other urban rivers sampled by NAWQA nationally. Detection frequency and concentrations of volatile organic compounds generally were higher in the two NECB streams than in the New York City area streams or in other urban NAWQA streams.

Water-Resources Investigations Report↗

Hydrogeology of the unconsolidated sediments, water quality, and ground-water/surface-water exchanges in the Methow River Basin, Okanogan County, Washington

The U.S. Geological Survey, in cooperation with Okanogan County, investigated the hydrogeology of the unconsolidated sedimentary deposits in the Methow River Basin, the quality of surface and ground waters, and the exchanges between ground water and surface water. Alluvium (Qa) and glaciofluvial sediments (Qga) deposited during the Quaternary period constitute the primary aquifer in the Methow River Basin, which is used as a source of water for domestic and public-water supplies and for maintaining streamflow during seasonal dry periods. The sediments form a nearly continuous unit along the valley bottom from above the Lost River to the confluence of the Methow and Columbia Rivers, covering more than 45 square miles of the basin?s surface. There are no distinct units within the deposit that can be identified across or along the valley except for fragments of a possible lake bed near the town of Twisp. Ground-water levels in the unconsolidated aquifer are highest during the summer and lowest in the winter and early spring. Ground water and surface water, sampled during June and September 2001, generally were of high quality. Only two samples from domestic and municipal wells indicated the possibility of ground-water contamination from nitrate and arsenic concentrations. In both cases, potential contamination was isolated to an individual well. No trends in water quality were apparent when comparing the results of this investigation with previous studies. The flow of water between rivers and aquifers is important for regulating the availability of water resources for in-stream and out-of-stream uses in the Methow River Basin. Ground-water discharge from the unconsolidated aquifer to the Methow River from Lost River to Pateros ranged from an estimated 153,000 acre-ft in water year 2001 to 157,000 acre-ft in water year 2002. In contrast, ground-water discharge to the lower Twisp River from Newby Creek to near Twisp ranged from 4,700 acre-ft in water year 2001 to 9,200 acre-ft in water year 2002. The Methow and Twisp Rivers, among others in the basin, are major sources of recharge for the unconsolidated aquifer, particularly during high-flow periods in May and June. Aquifer recharge by both rivers increased with streamflow in water year 2002 compared to water year 2001 as indicated by daily losses of streamflow. Aquifer recharge by the Methow River from Lost River to Pateros was estimated to be 82,000 acre-ft in water year 2001 and 137,000 acre-ft in water year 2002. Aquifer recharge by the Twisp River from Newby Creek to near Twisp was estimated to be 2,000 acre-ft in water year 2001 and 6,400 acre-ft in water year 2002. Seepage from unlined irrigation canals also recharges the unconsolidated aquifer during the late spring and summer and may contribute as much 38,000 acre-ft annually to aquifer recharge in the basin. Some portion of this ground water returns to rivers as indicated by a seasonal increase in ground-water discharge in the Methow River from Winthrop to Twisp and in the lower Twisp River during late summer and early autumn. Although the increase is likely due primarily to irrigation canal seepage, however, fluvial recharge during the summer also may have contributed to the increase. The increased rate of ground-water discharge decays by January in both reaches.

Washington↗

Aquifer-test results, direction of ground-water flow, and 1984-90 annual ground-water pumpage for irrigation, lower Big Lost River Valley, Idaho

The study area (see index map of Idaho), part of the Big Lost River drainage basin, is at the northern side of the eastern Snake River Plain. The lower Big Lost River Valley extends from the confluence of Antelope Creek and the Big Lost River to about 4 mi south of Arco and encompasses about 145 mi 2 (see map showing water-level contours). The study area is about 18 mi long and, at its narrowest, 4 mi wide. Arco, Butte City, and Moore, with populations of 1,016, 59, and 190, respectively, in 1990, are the only incorporated towns. The entire study area, except the extreme northwestern part, is in Butte City. The study area boundary is where alluvium and colluvium pinch out and abut against the White Knob Mountains (chiefly undifferentiated sedimentary rock with lesser amounts of volcanic rock) on the west and the Lost River Range (chiefly sedimentary rock) on the east. Gravel and sand in the valley fill compose the main aquifer. The southern boundary is approximately where Big Lost River valley fill intercalates with or abuts against basalt of the Snake River Group. Spring ground-water levels and flow in the Big Lost River depend primarily on temperature and the amount and timing of precipitation within the entire drainage basin. Periods of abundant water supply and water shortages are, therefore, related to the amount of annual precipitation. Surface reservoir capacity in the valley (Mackay Reservoir, about 20 mi northwest of Moore) is only 20 percent of the average annual flow of the Big Lost River (Crosthwaite and others, 1970, p. 3). Stored surface water is generally unavailable for carryover from years of abundant water supply to help relieve drought conditions in subsequent years. Many farmers have drilled irrigation wells to supplement surface-water supplies and to increase irrigated acreage. Average annual flow of the Big Lost River below Mackay Reservoir near Mackay (gaging station 13127000, not shown) in water years 1905, 1913-14, and 1920-90 was about 224,600 acre-ft; average annual flow of the Big Lost River near Arco (gaging station 13132500; see map showing water-level contours) in water years 1947-61, 1967-80, and 1983-90 was about 79,000 acre-ft (Harenberg and others, 1991, p. 254-255). Moore Canal and East Side Ditch divert water from the Big Lost River at the Moore Diversion, 3 mi north of Moore (see map showing water-level contours) and supply water for irrigation near the margins of the valley. When water supply is average or greater, water in the Big Lost River flows through the study area and onto the Snake River Plain, where it evaporates or infiltrates into the Snake River Plain aquifer. When water supply is below average, water in the Big Lost River commonly does not reach Arco; rather, it is diverted for irrigation in the interior of the valley, evaporates, or infiltrates to the valley-fill aquifer. This report describes the results of a study by the U.S. Geological Survey, in cooperation with the Idaho Department of Water Resources, to collect hydrologic data needed to help address water-supply problems in the Big Lost River Valley. Work involved (1) field inventory of 81 wells, including 46 irrigation wells; (2) measurement of water levels in 154 wells in March 1991; (3) estimation of annual ground-water pumpage for irrigation from 1984 through 1990; and (4) analysis of results of an aquifer test conducted southwest of Moore. All data obtained during this study may be inspected at the U.S. Geological Survey, Idaho District office, Boise.

Idaho↗

Sources, instream transport, and trends of nitrogen, phosphorus, and sediment in the lower Tennessee River basin, 1980-96

In 1997, the U.S. Geological Survey (USGS) began an assessment of the lower Tennessee River Basin as part of the National Water-Quality Assessment Program. Existing nutrient and sediment data from 1980 to 1996 were compiled, screened, and interpreted to estimate watershed inputs from nutrient sources, provide a general description of the distribution and transport of nutrients and sediments in surface water, and evaluate trends in nutrient and sediment concentrations in the lower Tennessee (LTEN) River Basin. Nitrogen inputs from major sources varied widely among tributary basins in the LTEN River Basin. Point source wastewater discharges contributed between 0 and 0.61 tons per square mile per year [(tons/mi 2 )/yr]. Of the nonpoint sources of nitrogen for which inputs were estimated (atmospheric deposition, nitrogen fixation, fertilizer application, and livestock waste) livestock waste contributed the largest input in about two-thirds (7 out of 11) of the tributary basins, and fertilizer application contributed the largest input in the remaining 4 basins. Nitrogen input from fertilizer application was the most variable spatially among the nonpoint sources of nitrogen, ranging from 1.5 to 23 (tons/mi 2 )/yr. Atmospheric deposition estimates varied the least from basin to basin, ranging from 1.6 to 2.0 (tons/mi 2 )/yr. Estimates of nitrogen input from livestock waste ranged between 2.0 to 13 (tons/mi 2 )/yr. The percentage of the input from each of these nonpoint sources that entered the surface-water system is not known. Wastewater discharge contributed between 0 and 0.14 (ton/mi 2 )/yr of phosphorus to tributary basins. Livestock waste contributed most of the input in 8 out of the 11 basins, and fertilizer application contributed the most in the remaining 3 basins. Estimates of phosphorus input for fertilizer application ranged from 0.35 to 5.1 (tons/mi 2 )/yr and from 0.62 to 4.3 (tons/mi 2 )/yr from livestock waste. Reservoirs on the main stem of the Tennessee River and on the Duck and Elk Rivers affect nutrient transport because hydrodynamic conditions in the reservoirs promote assimilation by aquatic plants and deposition of particulate matter. Observed decreases in total nitrite plus nitrate and dissolved-orthophosphorus concentrations in reservoirs or at sites downstream of reservoirs during summer months were probably related to seasonality of plant growth. Nutrient and sediment data used to estimate annual instream loads and yields were compiled from various water-quality monitoring programs and represent the best available data in the LTEN River Basin, but these data have several characteristics that limit accuracy of load estimates. Many of the monitoring programs were not designed with the objective of annual load estimation, and data representing storm transport are, therefore, sparse; sampling and analytical methods varied through time and among the monitoring programs, hampering spatial and temporal comparisons. The load estimates computed from these data are useful for evaluating broad spatial patterns of instream load, and comparisons of instream load to inputs, but may not be sufficiently accurate for local-scale evaluations of water quality. Estimates of the mean annual instream load of total nitrogen entering (Chattanooga, Tenn.) and leaving (Paducah, Ky.) the LTEN River Basin were 29,000 and 60,000 tons per year (tons/yr), respectively. These estimates represent a gain of 31,000 tons/yr, on average, across the area (18,930 mi 2 ) between these inlet and outlet sites. The sum of the mean annual instream load from gaged tributaries to the main stem within the study unit was 14,000 tons/yr; however, this number cannot be directly compared with the gain between the inlet and outlet sites because (1) the gaged area represents only 30 percent of the total area and (2) the period of record at many tributary sites did not correspond with the period of record at the inlet or outlet sites. Estimates of mean annual instream load of total phosphorus at the inlet and outlet sites of the LTEN River Basin were 1,300 and 5,000 tons/yr, respectively, representing a gain of 3,700 tons/yr, on average, across the study unit. The sum of the gaged tributary load, representing only 28 percent of the area contributing to the main stem, was 4,300 tons/yr. Although this number cannot be closely compared with the gain throughout the study unit, for the same reasons given for total nitrogen, a general comparison suggests that the main stem of the Tennessee River and the tributary embayments along the main stem function as a sink for total phosphorus, removing a substantial amount from the water column through deposition or assimilation. The estimates of inputs can be compared and correlated with yields (area-normalized instream loads); significant correlations between estimates of inputs and yields might be useful as predictive tools for instream water quality where monitoring data are not available. Yields of nitrogen correlated moderately well with inputs from nonpoint sources, based on 1992 estimates. Nitrogen yield was highest [3.5 (tons/mi 2 )/yr] for Town Creek, for which the balance of nonpoint-source inputs to agricultural lands (fertilizer application plus nitrogen fixation plus livestock waste minus harvest) was also the highest [15 (tons/mi 2 )/yr]. Nitrogen yield was low [1.0 (tons/mi 2 )/yr] for the Buffalo River, for which the balance of agricultural nonpoint-source input was correspondingly low [3.2 (tons/mi 2 )/yr, the second lowest]. Correlation of wastewater discharge with yield was poor, and contrasted with the significant correlation between wastewater discharge and median nitrogen concentration during low streamflow. The poor correlation between wastewater discharge and annual yield was expected, however, as wastewater discharge is a small fraction compared with annual yield. In contrast with nitrogen, phosphorus yield did not correlate well with any estimated inputs or land-use types for the tributary basins. Phosphorus yield was highest [1.1 and 0.93 (tons/mi 2 )/yr] at two sites along the Duck River and at Elk River near Prospect [0.89 (ton/mi 2 )/yr]; however, estimates of inputs at these sites were in the middle of their respective ranges. The influence of the outcrop of phosphatic limestone formations of the brown-phosphate districts in the lower Duck and lower Elk River Basins might be responsible for the poor correlation between estimated inputs and yields of phosphorus. The outcrop pattern of these phosphatic limestones are an important factor to consider as regional boundaries are established for attainable, region-specific water-quality criteria for total phosphorus. Estimates of sediment input from cropland soil erosion in 1992 ranged from 51 to 540 (tons/mi 2 )/yr among the major hydrologic units in the LTEN River Basin. Information was not available to estimate this input for individual tributaries. Sediment yield estimates ranged from 65 to 263 (tons/mi 2 )/yr for the three tributary monitoring basins for which instream data were available, and from 17 to 26 (tons/mi 2 )/yr for the Tennessee River at South Pittsburg and at Pickwick Landing Dam, respectively. Lower sediment yields for the main stem sites compared with the tributary sites is probably due to sediment deposition in the main stem of the Tennessee River and tributary embayments along the main stem. Most of the significant trends in nutrient concentrations from about 1985 to about 1995 were decreasing trends, except for total nitrite plus nitrate, which increased at one site on the Elk River. The spatial distribution of decreasing trends of total nitrogen and total ammonia corresponds with the spatial variation among basins in wastewater loading rate. The time period of observed trends corresponds to the period of improvements in municipal treatment, thus decreases in wastewater effluent concentrations of nitrogen might be responsible for the decreasing trend in instream concentrations at these sites. Concentrations of total phosphorus did not decrease during this period at these sites, as might have been expected considering the reductions in wastewater input of phosphorus during this period.

Alabama, Georgia, Kentucky, Mississippi, Tennessee↗

Diverse portfolios: Investing in tributaries for restoration of large river fishes in the Anthropocene

Rehabilitation of large Anthropocene rivers requires engagement of diverse stakeholders across a broad range of sociopolitical boundaries. Competing objectives often constrain options for ecological restoration of large rivers whereas fewer competing objectives may exist in a subset of tributaries. Further, tributaries contribute toward building a “portfolio” of river ecosystem assets through physical and biological processes that may present opportunities to enhance the resilience of large river fishes. Our goal is to review roles of tributaries in enhancing mainstem large river fish populations. We present case histories from two greatly altered and distinct large-river tributary systems that highlight how tributaries contribute four portfolio assets to support large-river fish populations: 1) habitat diversity, 2) connectivity, 3) ecological asynchrony, and 4) density-dependent processes. Finally, we identify future research directions to advance our understanding of tributary roles and inform conservation actions. In the Missouri River United States, we focus on conservation efforts for the state endangered lake sturgeon, which inhabits large rivers and tributaries in the Midwest and Eastern United States. In the Colorado River, Grand Canyon United States, we focus on conservation efforts for recovery of the federally threatened humpback chub. In the Missouri River, habitat diversity focused on physical habitats such as substrate for reproduction, and deep-water habitats for refuge, whereas augmenting habitat diversity for Colorado River fishes focused on managing populations in tributaries with minimally impaired thermal and flow regimes. Connectivity enhancements in the Missouri River focused on increasing habitat accessibility that may require removal of physical structures like low-head dams; whereas in the Colorado River, the lack of connectivity may benefit native fishes as the disconnection provides refuge from non-native fish predation. Hydrologic variability among tributaries was present in both systems, likely underscoring ecological asynchrony. These case studies also described density dependent processes that could influence success of restoration actions. Although actions to restore populations varied by river system, these examples show that these four portfolio assets can help guide restoration activities across a diverse range of mainstem rivers and their tributaries. Using these assets as a guide, we suggest these can be transferable to other large river-tributary systems.

Frontiers in Environmental Science↗

Wind River subbasin restoration: Annual report of US..Geological Survey activities, January 2018 through December 2018

We sampled juvenile wild Steelhead Oncorhynchus mykiss in headwater streams of the Wind River, WA, to characterize populations and investigate life-history metrics, particularly migratory patterns. We used Passive Integrated Transponder (PIT)-tagging and a series of instream PIT-tag interrogation systems (PTISs) to track juveniles. The Wind River subbasin is considered a wild Steelhead refuge by Washington Department of Fish and Wildlife (WDFW). No hatchery Steelhead have been planted in the Wind River subbasin since 1997, and hatchery adults are estimated to be less than one percent of spawners in most years (pers comm. Thomas Buehrens, Washington Department of Fish and Wildlife). Our repeated headwater sampling of consistent sites in the Wind River subbasin has also allowed us to track relative abundance of Brook Trout, a non-native species to the Wind River. Our work is contributing to understanding of Steelhead population response to numerous restoration actions in the subbasin, including removal of Hemlock Dam from Trout Creek in 2009, where our PTISs are helping to quantify adult response. Data from our study, and companion work by Washington Department of Fish and Wildlife, are contributing to Bonneville Power Administration’s (BPA) Research Monitoring and Evaluation (RM&E) Program Strategy of Fish Population Status Monitoring (www.cbfish.org/ProgramStrategy.mvc/ViewProgramStrategySummary/1). Specifically this work addresses the sub-strategies of: 1) Assessing the Status and Trends of Diversity of Natural Origin Fish Populations and to Uncertainties Research regarding differing life histories of a wild Steelhead population, 2) Assessing the Status and Trend of Adult Natural Origin Fish Populations, and 3) Monitoring and Evaluating the Effectiveness of Tributary Habitat Actions Relative to Environmental, Physical, or Biological Performance Objectives. Our headwaters parr PIT tagging, WDFW parr, smolt, and adult tagging and our instream PTISs are providing data on movements and life histories of parr, smolt, and adult Steelhead. During summer 2018, we PIT-tagged 1,592 age-0 and age-1 Steelhead parr in headwater areas of the Wind River subbasin to characterize population traits and investigate life-history diversity, including growth and pre-smolt downstream movement. Repeat headwater sampling and smolt trap operations provide opportunities for recapture, and instream PTISs and Columbia River infrastructure provide opportunity for detection of PIT-tagged fish. Throughout the year, we maintained a series of six instream PTISs to monitor movement of tagged Steelhead parr, smolts, and adults. Detections at the instream PTISs have demonstrated trends of age-0 and age-1 parr emigration from natal areas during summer and fall, in addition to the expected movement of parr and smolts in spring. Substantial numbers of parr make downstream movements as age-1 fish. We have estimated that from 15 to 33 percent of parr tagged as age-0 fish make downstream migrations at age-1 for additional rearing. We have estimated that from 1 to 27 percent of parr tagged as age-1 fish make downstream migrations during fall. These findings raise many questions about parr rearing strategies, habitat use, and success of these migrants and suggest a need for broader monitoring of juvenile Steelhead in some river systems to fully document juvenile production. Long-term monitoring of PIT-tagged fish is providing information on contribution of various life-history strategies to smolt production and adult returns. Movements of PIT-tagged adult Steelhead were recorded at instream PTISs. These data have allowed assessment of adult returns to tributary watersheds within the Wind River subbasin. Detection efficiency of adult PIT-tagged Steelhead at our primary adult-monitoring PTIS in Trout Creek has been greater than 92 percent during 6 of the past 7 years. This is providing excellent data to estimate adult returns to this watershed. Determination of adult use of tributary watersheds is providing data to help evaluate the efficacy of the removal of Hemlock Dam on Trout Creek. Hemlock Dam, located at rkm 2.0 of Trout Creek, was removed in summer 2009. The dam contributed to hydrologic impairment of Trout Creek and had potential negative effects on Steelhead. The improvements made to the upper Wind River PTIS (site code WRU at rkm 28.3; better site characteristics and grid power) during 2016 and 2017, and a planned new site in the Mine Reach of the upper Wind River, will allow estimates of subbasin adult escapement like those in Trout Creek. During 2018, we also completed planning and permitting with U.S. Forest Service for a new PTIS site at rkm 36 of the Wind River (the Mine Reach, mentioned above). This site will replace two sites (one in Paradise Creek and one at rkm 41 of the Wind River), which had operational challenges due to lack of adequate solar power and winter difficulties. The new Mine Reach PTIS site at rkm 36, will have better solar exposure, fewer winter operations difficulties, and provide opportunity to detect fish from juvenile sampling sites that were downstream of the previous two PTISs. The more consistent operation of the new Mine Reach PTIS site will increase our ability to estimate migrant abundance as all the juveniles tagged upstream of it will be subject to the same potential detection history, instead of three different potential detection histories as before. Additionally, with the new Mine Reach PTIS site lower in the watershed, it will subject more PIT-tagged adult Steelhead to detection and provide ability to generate a nonbiased adult-detection efficiency estimate for the WRU PTIS at rkm 28.3 of the Wind River. This will provide the opportunity to estimate yearly adult Steelhead abundance to the upper Wind watershed area. Permitting is complete and some supplies have been purchased to build and install this new site in 2019. Repeat sampling at consistent locations in the subbasin has allowed investigation into juvenile Steelhead growth patterns. Growth rates (relative change in weight) of age-0 PIT-tagged parr during summer are similar across the subbasin, but lower for age-1 parr in the Trout Creek watershed than the upper Wind River watershed. Yearly growth for parr tagged at age-0 is similar across the subbasin. Yearly growth for parr tagged at age-1 is lowest in Martha Creek, but similar elsewhere. Non-native Brook Trout are present in portions of the subbasin, chiefly the Trout Creek watershed, and repeat sampling has allowed us to index their prevalence. Percentage of catch that is Brook Trout at each of four sample sites in Trout Creek have declined from the period 1998 – 2003 to the period 2011 – 2018. There was a pattern of decline in percent of catch and number of Brook Trout at the Trout Creek sites from 2011 through 2016, though a slight upward trend during 2017 and 2018 has been evident. Evaluating and planning restoration efforts are of interest to many managers and agencies to ensure efficient use of resources. The evaluation of various life-histories of Steelhead within the Wind River subbasin will provide information to better track populations, and to direct habitat restoration and water allocation planning. Movement of Steelhead parr raises many questions regarding estimating juvenile abundance, origin, and habitat use within watersheds. Improved PTISs and focused PIT tagging of age-0 and age-1 Steelhead parr are increasingly allowing us to investigate such questions. Increasingly detailed Viable Salmonid Population information, such as that provided by PIT-tagging and instream PTISs networks like those in the Wind River subbasin, provide data to inform policy and management, as life-history strategies and production bottlenecks are identified and understood.

Washington↗

Wind River Subbasin Restoration Annual Report of USGS Activities January 2021 through December 2022

We sampled juvenile wild Steelhead Trout Oncorhynchus mykiss in headwater streams of the Wind River, WA, to characterize population attributes and investigate life-history metrics, particularly migratory patterns, and early life-stage survival. We used passive integrated transponder (PIT) tagging and a series of instream PIT-tag interrogation systems (PTISs) to track juveniles and adults. The Wind River subbasin is considered a wild Steelhead refuge by Washington Department of Fish and Wildlife (WDFW). No hatchery Steelhead Trout have been released in the Wind River subbasin since 1997, and hatchery adults are estimated at less than one percent of spawners in most years. Over twenty years of Steelhead Trout status and trend monitoring and research in the subbasin is contributing to understanding of population response to numerous restoration actions in the subbasin, including removal of Hemlock Dam from Trout Creek in 2009, which had an outdated adult ladder and contributed to increased water temperatures reducing performance of juvenile Steelhead Trout. Data from our study, and companion work by Washington Department of Fish and Wildlife, are contributing to Bonneville Power Administrations (BPA) Research, Monitoring, and Evaluation (RM&E) Program Strategy of Fish Population Status Monitoring (https://www.cbfish.org/ProgramStrategy.mvc/Index). Specifically, this work addresses the sub-strategies of 1) Assessing the Status and Trends of Diversity of Natural Origin Fish Populations and Uncertainties Research regarding differing life histories of a wild Steelhead Trout population, 2) Assessing the Status and Trend of Adult Natural Origin Fish Populations, and 3) Monitoring and Evaluating the Effectiveness of Tributary Habitat Actions Relative to Environmental, Physical, or Biological Performance Objectives. During summer and fall 2021 and 2022, we PIT-tagged 1,889 and 1,391 Steelhead parr (age-0 and age-1), respectively, in the Trout Creek and upper Wind River watersheds. Age-0 parr were at lower densities in 2022 than many years due to a poor return of adult Steelhead spawners in 2022. Steelhead Trout parr were recaptured and detected through repeat headwater sampling, smolt trap operations, and instream PTISs and Columbia River PIT-tag detection infrastructure. We maintained, and upgraded in 2022, a series of six instream PTISs to monitor movement of tagged Steelhead Trout parr, smolts, and adults, providing data to population assessments, and life-cycle research and modeling. We continue to improve our PTISs in the Wind River subbasin. The improvements in siting and addition of grid power to the upper Wind River PTIS (site code WRU, rkm 27.6) during 2016 and 2017, and the addition of the Mine Reach site (site code MIN, rkm 36.0) have much improved PIT-tagged fish monitoring in the upper Wind River watershed. The paired PTIS design in the upper Wind River watershed (sites WRU and MIN) matches that in the Trout Creek watershed (sites TRC, rkm 2.0; and TC4, rkm 11.5) and will allow comparisons of Steelhead Trout population metrics between the two watersheds as response to Hemlock Dam removal continues and future restoration efforts occur in Trout Creek. During summer 2022, we upgraded three PTISs with new transceivers and new or reconfigured antennas. We replaced the Biomark 1001 Multiplexing Transceivers with Biomark MTS IS1001 Master Controller and individual IS1001 Transceivers at WRU, TRC (Trout Creek, rkm 2.0), and TC4 (Trout Creek at 43 Road Bridge, rkm 11.5). These new transceivers and antennas will improve detection performance due to increased read range and decreased susceptibility to noise. We also installed an additional IS1001 Transceiver and 11-foot antenna at WRA in summer 2021 to increase cross-channel and water column coverage. Detection data from PIT-tagged adult Steelhead Trout at PTISs allow assessment of adult escapement to tributary watersheds within the Wind River subbasin. Adult Steelhead Trout detection efficiency estimates at our primary PTIS in Trout Creek have been greater than 99 percent during six of the past eight years and have exceeded 97% at our primary PTIS in the Wind River during seven of the past eight years. Adult escapement estimates to tributary watersheds are helping us evaluate the efficacy of the 2009 removal of Hemlock Dam from rkm 2.0 of Trout Creek. The dam had potential negative effects on Steelhead Trout populations in Trout Creek due to hydrologic impairment, increased temperatures, and adult passage issues. Hemlock Dam was laddered for adult passage, but not to modern standards, which likely resulted in avoidance by some adult Steelhead Trout. Detections at the instream PTISs have demonstrated trends of age-0 and age-1 parr emigration from natal areas during summer and fall, in addition to the expected movement of parr and smolts in spring. We have estimated that from 15 to 51% of parr tagged as age-0 fish in headwater areas make downstream migrations at age 1 for additional rearing. Downstream movement occurs primarily during spring but also in fall. We have estimated that up to 27% of Steelhead Trout parr, tagged as age-1 fish, make downstream migrations during fall. Fall migration of age-1 parr has been more common in the upper Wind River watershed than the Trout Creek watershed. These findings raise questions about where parr most successfully rear and whether migrations are density- or habitat-quality driven. Broader monitoring programs would give a more comprehensive understanding of juvenile Steelhead Trout production and rearing and contributions to adult recruitment from varied rearing strategies. Repeat sampling at consistent locations in the subbasin has enabled assessment of juvenile Steelhead Trout growth patterns. Growth rates (relative change in weight) of age-0 PIT-tagged parr during summer were similar across the subbasin, though slightly lower in the Trout Creek watershed. The greatest summer growth rate was in the mainstem of the Wind River (rkm 37 and 41). Summer growth rates were lower for age-1 parr in the Trout Creek watershed than the upper Wind River watershed. Yearly relative growth was similar across the subbasin for both age-0 and age-1 tagged parr. Lower Layout Creek had the highest yearly growth rate of parr from age-0 to age-1. Mainstem Wind River (rkm 37) had the highest yearly growth rate of parr from age-1 to age-2. Non-native Brook Trout Salvelinus fontinalis are present in the subbasin, chiefly the Trout Creek watershed, and repeat sampling provides an index of their prevalence. Mean percent-of-catch that is Brook Trout, at four sample sites in Trout Creek, has declined from the period 1998 2003 to the period 2011 2022. Percent-of-catch and number of Brook Trout at the Trout Creek sites from 2011 through 2022 has generally declined, though both metrics have been somewhat variable. Evaluation and planning of habitat restoration efforts are critical to ensure efficient use of money and resources. Assessing Steelhead Trout life history variation in the Wind River subbasin will inform research and tracking of many populations and help inform habitat restoration and water allocation planning. Movement of Steelhead Trout parr from natal areas to other rearing areas raises questions regarding juvenile abundance, origin, and habitat use within watersheds. Improved PTISs and focused PIT-tagging of age-0 and age-1 Steelhead Trout parr allow investigation of such questions. Increasingly detailed viable salmonid population information, such as that provided by PIT-tagging and instream PTIS networks like those in the Wind River, can provide data to inform fisheries policy and management and understand life-history strategies and limiting factors. Such efforts also enable assessment of long-term effects of habitat restoration actions such as the removal of Hemlock Dam on Trout Creek, and the proposed Stage-0 restoration effort for upper Trout Creek, which would be a large-scale effort to reset sections of stream within their floodplain, restoring connectivity and interaction with surrounding landscape.

Report↗