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At least 1,495 records · Page 83Linked to original sources

Sediment storage and transport in the Nooksack River basin, northwestern Washington, 2006–15

The Nooksack River is a dynamic gravel-bedded river in northwestern Washington, draining off Mount Baker and the North Cascades into Puget Sound. Working in cooperation with the Whatcom County Flood Control Zone District, the U.S. Geological Survey studied topographic, hydrologic, and climatic data for the Nooksack River basin to document recent changes in sediment storage, long-term bed elevation trends, rates of sediment transport, and factors influencing surficial drainage in order to support ongoing river management. Differences in elevations between topographic and bathymetric surveys in 2005/06 and 2013/15 indicate the active channel aggraded about 1–2 feet locally near the cities of Ferndale and Everson but was primarily stable between them. The active channel upstream of Nugent’s Corner generally incised. Total incision upstream of Nugent’s Corner to Glacier Creek generated 2.3 ± 1.7 million cubic yards of sediment from 2005/06 to 2013 and likely represented a significant source of coarse sediment to the lower mainstem river over that time. Long-term records of local channel-bed elevation, derived from U.S. Geological Survey streamgage data, show bed-elevation changes of about 1–3 feet. The river bed at most streamgages exhibits long-term trends, with relatively consistent rates of change on the order of 1 foot per decade that persist years to decades. Lagged correlations in bed-elevation trends at all seven streamgages in the North Fork Nooksack and mainstem Nooksack suggest that decadal periods of persistent aggradation and incision originate in the North Fork and translate downstream. The channel-change signal propagates downstream 0.5–2.5 miles per year, with the rate of propagation scaling closely with channel slope. The pattern of incision and aggradation in the North Fork correlates with regional climate, where persistent incision follows extended cold and wet periods, and persistent aggradation follows extended warm and dry periods. Climate-driven variation in coarse-sediment delivery, primarily from the North Fork Nooksack, then appears to be a strong control on long-term vertical channel adjustments at sites downstream. The downstream-translating climate signal generated in the North Fork would account for recently observed aggradation at Everson and Ferndale but not the observed incision in unconfined reaches upstream of Nugent’s Corner from 2005–06 to 2013. This mismatch indicates that understanding how changes in sediment-supply influence those unconfined reaches remains a key uncertainty for predicting future channel change. Continuous turbidity monitoring integrated with suspended sediment and limited bedload sampling were used to calculate annual sediment loads at five sites in the basin. The sediment load in the lower river at Ferndale ranged from 0.78 to 1.17 million tons per year and averaged 0.97 million tons per year for WYs 2012–17. Suspended sediment made up 93 percent of the load, and bedload made up 7 percent. Most of the fine sediment load of the lower river is supplied from headwaters of the North, Middle, and South Fork Nooksack basins, with relatively little net increase in fine sediment loads in the lower mainstem basin. The three forks supply approximately equal proportions of the lower-river fine sediment load. However, the glacially sourced North and Middle Fork Nooksack basins carry a notably sandier suspended-sediment load than the South Fork Nooksack. A comparison of monthly streamflow and precipitation trends since 1981 indicate statistically significant increases in total spring precipitation and the number of spring days with measurable precipitation in much of the basin, as well as increases in mean spring river stage near Ferndale. Since no trends in mean spring discharge are observed, the trends in river stage are attributed primarily to observed changes in bed elevation. Changes in bed elevation and precipitation may then both have plausibly impacted field drainage in the lower river below Ferndale.

Washington↗

Streamflow gains and losses in New Fork and Green Rivers, upstream from Fontenelle Reservoir, Wyoming, October 2015

The Wyoming Landscape Conservation Initiative is a program created to implement a long-term, science-based program of assessing natural resources while facilitating responsible energy and other development and does studies in much of southwestern Wyoming, including all or parts of Lincoln, Sublette, Fremont, Sweetwater, and Carbon Counties. A synoptic study was completed by the U.S. Geological Survey as part of ongoing contributions to the Wyoming Landscape Conservation Initiative to better understand the streamflow dynamics in the New Fork and Green Rivers in an area with historical, current, and future energy development. Streamflow measurements were collected October 19–22, 2015, at 19 sites on the New Fork and Green Rivers in Wyoming to determine changes in streamflow and, where applicable, describe the inflow and outflow of groundwater. Streamflow in the New Fork River generally increased from 50 cubic feet per second (ft 3 /s) at the most upstream site near Pinedale, Wyoming, to 350 ft 3 /s at the mouth of the river. Streamflow in the Green River generally increased downstream from 250 ft 3 /s at the most upstream site at Warren Bridge to around 800 ft 3 /s at the most downstream site near La Barge, Wyo., upstream from Fontenelle Reservoir. Estimated streamflow gains and losses were calculated for five reaches on the New Fork River. Four of the five reaches on the New Fork River had a change greater than the associated measurement error and were gaining reaches; the reach with the largest gain was the most upstream reach. One reach, the most downstream reach, had a calculated change in streamflow less than the associated measurement error. Estimated streamflow gains and losses were calculated for four reaches on the Green River. One reach was determined to be a gaining reach, one was a losing reach, and two reaches had changes less than the associated measurement error. Comparing the annual streamflow hydrographs for three long-term streamgages likely showed the effects of applying irrigation water to the upstream areas of land draining to the Green and New Fork Rivers. Streamflows in the New Fork River near Big Piney and the Green River near La Barge, Wyo., are sustained later in the season compared to the upstream site of Green River at Warren Bridge, which has few diversions and minimal irrigation.

Wyoming↗

Quantifying the eroded and deposited mass of mercury-contaminated sediment by using terrestrial laser scanning at the confluence of Humbug Creek and the South Yuba River, Nevada County, California, 2011–13

High-resolution, terrestrial laser scanning, also known as ground-based lidar (light detection and ranging), was used to quantify the volume of mercury-contaminated sediment eroded from an outcrop of historical placer-mining debris at the confluence of Humbug Creek and the South Yuba River in the Sierra Nevada foothills, about 17 kilometers northeast of Grass Valley, California, and delivered to a zone below an observed flood stage of the South Yuba River. Substantial quantities of mercury were used and lost to the environment from historical placer gold mining activities on the western slope of the Sierra Nevada, California, and recent studies have documented continued persistence of mercury and methylmercury concentrations in water, sediment, fish, and predatory invertebrates in the Yuba River drainage basin in relation to suspected mercury sources. To identify areas that have high levels of mercury contamination as possible remediation targets in the Yuba River drainage basin and other areas in the Sierra Nevada, the U.S. Geological Survey worked in cooperation with the Bureau of Land Management on this and other detailed studies. Malakoff Diggings, one of the largest hydraulic gold mines in the Sierra Nevada, is 3.5 kilometers north of the study site in the Humbug Creek subbasin. Terrestrial laser scanning was used to produce centimeter-scale, three-dimensional maps of the complex outcrop surface, which was composed of an upper erosional area (cliff and over-steepened slope) and a lower depositional area (colluvial slope). The outcrop could not be mapped non-destructively or in sufficient detail by traditional surveying techniques. The study site, which was approximately 70 meters long, 30 meters wide and 20 meters high, was surveyed four times in 2 years (December 15, 2011; October 25, 2012; January 4, 2013; and November 22, 2013) to determine volumetric differences in the upper erosional and lower depositional areas between surveys. Measured changes in volume for the upper erosional area and lower depositional area were multiplied by the corresponding sediment density so that a mass-balance relationship, between the eroded and deposited sediment during each period, could be used to estimate the amount of mercury-contaminated sediment that was transported to below the base of the colluvial slope, where it could be mobilized by the South Yuba River during a flood having a 5-to-10-year recurrence interval. On December 2, 2012, a flood of this estimated magnitude reached the base of the colluvial slope. Between the first and second surveys (December 15, 2011–October 25, 2012), an estimated mass of 18±9.2 kilograms of sediment was transported from steeper slopes to the gently sloping river bank below the base of the colluvial slope. Between the second and third surveys (October 25, 2012–January 4, 2013), an atmospheric river caused heavy precipitation at the study site during late November and early December 2012. This short-duration, high-intensity rain resulted in a large amount of erosion and deposition at the study site and also caused high streamflow (flood stage) in the South Yuba River. From October 2012 to January 2013, 51±31 kilograms of sediment was transported to below the base of the colluvial slope, that is, below the high-water mark of December 2, 2012. Between the third and fourth surveys (January 4, 2013–November 22, 2013), an additional 10±26 kilograms of sediment was transported to below the base of the colluvial slope. During the 24 months of the study, the total mass of sediment delivered below the base of the colluvial slope and the high-water mark of December 2, 2012, was 79±66 kilograms. In any given year there is a 10–20-percent chance (5-to-10-year recurrence interval) of a flood equal to or greater than that of the December 2, 2012, flood, which could transport mercury-contaminated sediment at the study site into the South Yuba River. Hydraulically modeled estimates of the South Yuba River stage during floods having a 50- and 100-year recurrence interval (2- and 1-percent annual exceedance probability, respectively) indicated that resulting river stages could be 2.2–3.0 meters above the base of the colluvial slope, or 2.2–3.0 meters above the high-water mark of December 2, 2012. Such high river stages would be likely to inundate the lower half of the colluvial slope and mobilize a substantial volume of mercury-contaminated sediment to downstream areas.

California↗

Water-quality trends for selected sites and constituents in the international Red River of the North Basin, Minnesota and North Dakota, United States, and Manitoba, Canada, 1970–2017

A comprehensive study to evaluate water-quality trends, while considering natural hydroclimatic variability, in the Red River of the North Basin and assess water-quality conditions for the Red River of the North crossing the international boundary near Emerson, Manitoba, Canada (the binational site), was completed by the U.S. Geological Survey in cooperation with the International Joint Commission, North Dakota Department of Environmental Quality, and Minnesota Pollution Control Agency and in collaboration with Manitoba Sustainable Development and Environment and Climate Change Canada. The international Red River of the North Basin encompasses 3 U.S. States (South Dakota, North Dakota, and Minnesota) and 1 Canadian Province (Manitoba). Water quality in the Red River of the North Basin is of concern for both Federal governments and State and Provincial governments. Water-quality objectives have been previously established for selected dissolved ions and recently (2019) proposed for selected nutrients for the binational site. In the current (2020) study, water-quality data from State, Provincial, and Federal agencies in the United States and Canada for sites in the Red River of the North Basin from 1970 to 2017 were compiled and used for trend analysis. Trend analysis using a water-quality dataset from multiple agencies that collect water-quality data for various objectives presented multiple challenges. The trend-analysis approach was able to accommodate differences in water-quality data caused by field-collection and laboratory-analytical method differences, disparities in sampling frequencies, and spatial and temporal gaps in data. Most of these challenges were overcome by the statistical tool, R–QWTREND, which identifies trends in concentration unrelated to variability in streamflow. The integrated basin approach used in the current study, combined with comparing current data trends with historical trends, provided valuable insights into understanding how water quality is changing spatially (34 sites analyzed for a recent period, 2000–15) and temporally (5 sites analyzed for a 45-year historical period, 1970–2015) within the Red River of the North Basin. One of the most consistent spatial and temporal changes observed in the current study was increasing concentrations of sulfate among tributary and main-stem sites since 2000. For some sites, increases were detected starting as early as 1985. Total dissolved solids and chloride concentrations had spatial and temporal patterns like sulfate. Although R–QWTREND removes the variability in constituent concentration caused by natural streamflow variability, all variability in sulfate caused by hydroclimatic variability may not be captured because of changes in hydrologic pathways and changes in the contributions of sulfate from various natural sources. Nutrient concentrations demonstrated less consistent spatial and temporal changes than sulfate, and changes in nutrient concentrations were assumed to be more closely tied to human-induced rather than natural changes. Nitrate-plus-nitrite concentrations were mostly increasing in the upper Red River of the North subbasin, and for nitrate plus nitrite and total nitrogen, the Sheyenne River subbasin had consistent decreasing concentrations. Since 2000, total phosphorus has decreased in the upper Red River of the North subbasin, but total phosphorus concentration has increased for sites in the lower Red River of the North subbasin, and for some main-stem sites, concentrations have been increasing since 1985. Unlike sulfate, the pattern in historical trends for total phosphorus for the main-stem sites differed from tributary sites, indicating that human-induced changes affected tributaries and main-stem sites differently. The more detailed evaluation of flow-averaged water-quality conditions for the binational site provided an understanding of how loads have changed over time and what proportion of the year and season concentrations are expected to exceed water-quality objectives. In a basin with highly variable streamflow like the Red River of the North, the trend in flow-averaged load (assuming streamflow conditions are the same year after year) provided a robust measure of change over time. Increasing concentrations of sulfate, chloride, total dissolved solids, and total phosphorus since 1985 for the binational site resulted in longer periods of exceedance of water-quality objectives per year occurring over time. For total nitrogen, decreasing concentrations resulted in shorter periods of exceedance per year during 1980 to 2015, but concentrations were still expected to exceed the water-quality objective about half the year. Periods of when exceedances were likely to occur during the year were affected by the source and transport mechanisms of the constituent. Trend results from this effort identified how water quality has changed across the basin, and further investigation would help to identify causes for the trends observed here. Information from the current study provides a basis for future trend attribution studies, evaluation of water-quality objectives, and development of comprehensive strategies for reducing nutrients to desired targets and establishes a baseline for tracking future progress in the Red River of the North Basin.

Minnesota, North Dakota, South Dakota, Manitoba↗

Groundwater budgets for the Big Lost River Basin, south-central Idaho, 2000–19

The Big Lost River Basin, located in parts of Butte and Custer Counties in south-central Idaho, supports the communities surrounding the cities of Arco, Leslie, Mackay, and Moore and provides for agricultural resources that depend on a sustainable supply of surface water from the Big Lost River and its tributaries and groundwater from an unconfined aquifer. The aquifer, situated in a structurally controlled intermontane valley, is composed of unconsolidated alluvium, consolidated sedimentary and volcanic rocks, and younger interbedded volcanic rocks. This report presents two separate groundwater budgets for the aquifer, one above and one below Mackay Dam, as well as a combined groundwater budget for the aquifer within the entire Big Lost River Basin. The budgets span a 20-year period (2000–19), characterizing average conditions, a dry year (2014), and a wet year (2017). The groundwater budgets will help address questions regarding the availability of groundwater supply in the Big Lost River Basin and inform future groundwater modeling. The Idaho Geological Survey has prepared the groundwater budgets as part of a larger hydrogeologic investigation completed by the U.S. Geological Survey and the Idaho Geological Survey in cooperation with the Idaho Department of Water Resources during 2018–21. Other reports describe the hydrogeologic framework and several streamflow-measurement events to evaluate gains and losses on the Big Lost River. Collectively, these reports provide an updated characterization of groundwater resources in the Big Lost River Basin which will help address water resources challenges. A groundwater budget is a conceptual and numerical accounting of inflow (recharge) to groundwater and outflow (discharge) from groundwater. The predominant sources of recharge to the aquifer include losing river reaches (33 percent), areal recharge (as precipitation less evapotranspiration and surface runoff, comprising about 23 percent of the total inflow), tributary canyon underflow from higher altitudes (20 percent), canal seepage (13 percent), recharge through applied irrigation on fields below the root zone and other minor sources (11 percent), and Mackay Reservoir seepage (less than 1 percent). The primary sources of discharge from the aquifer are groundwater pumpage to meet irrigation demand, domestic supply, and municipal supply (76 percent) and gaining river reaches (24 percent). The positive or negative difference between the sum of all inflows and outflows is regarded as the residual, representing the change in groundwater storage, groundwater outflow from the basin or subbasins, and uncertainty and errors in the budget. In the Big Lost River Basin, groundwater outflow is at the mouth of the basin below Arco into the eastern Snake River Plain aquifer. The total mean annual estimated recharge to the Big Lost River Basin was 439,100 acre-feet per year (acre-ft/yr; 607 cubic feet per second [ft 3 /s]) for 2000–19, 373,900 acre-ft/yr (516 ft 3 /s) in 2014, and 762,100 acre-ft/yr (1,053 ft 3 /s) in 2017. The mean annual estimated groundwater discharge from the aquifer was about 112,300 acre-ft/yr (155 ft 3 /s) for 2000–19, 153,500 acre-ft/yr (212 ft 3 /s) in 2014, and 53,400 acre-ft/yr (74 ft 3 /s) in 2017. The estimated mean annual groundwater residual was 326,800 acre-ft/yr (451 ft 3 /s) for 2000–19, 220,400 acre-ft/yr (304 ft 3 /s) in 2014, and 708,700 acre-ft/yr (979 ft 3 /s) in 2017. The mean annual residual above Mackay Dam was 100,400 acre-ft/yr (2000-19), 96,700 acre-ft (2014), and 248,300 acre-ft (2017). The mean annual residual contribution below Mackay Dam, minus any groundwater-flow above Mackay Dam, was 226,400 acre-ft/yr (2000-19), 123,700 acre-ft (2014), and 460,400 acre-ft (2017). These results are highly sensitive to assumptions about certain budget inflow parameters. In particular, the magnitude of the budget residuals during especially dry and wet periods is amplified by the groundwater-budget terms tributary streamflow and tributary underflow that contribute appreciable recharge but also have high uncertainty. The results of the groundwater-budget evaluation describe an interconnected and complex hydrologic response throughout the basin to various climatic and water-use trends. The part of the basin above Mackay Dam typically has a positive groundwater residual derived from snowmelt recharge to tributary canyons and areal recharge in excess of groundwater pumpage for irrigation demand. This supply is used to meet irrigation demand above Mackay Dam and to provide for water supply below Mackay Dam. On average, groundwater inflow from above Mackay Dam to below Mackay Dam, assuming negligible reservoir storage effects, accounts for about 25 percent of the total groundwater recharge below Mackay Dam. Considerable recharge to groundwater below Mackay Dam occurs through seepage from the Big Lost River and canals and ditches. Most groundwater discharge from the aquifer is through irrigation pumping. The water supply below Mackay Dam is highly dependent on available upstream surface-water flows, the magnitude of the groundwater residual from above Mackay Dam, and annual variability in local groundwater conditions.

Idaho↗

Thermal heterogeneity and cold-water anomalies within the lower Yakima River, Yakima and Benton Counties, Washington

Warm water temperatures in the lower Yakima River in central Washington are key limitations to the restoration of Pacific salmon ( Onchorhynchus spp .) populations within the Yakima River Basin. Identification of the location and magnitude of cold-water anomalies, which are cooler than ambient river temperatures during summer months, and the processes that create and maintain them is needed to inform salmon restoration efforts within the Yakima River Basin. Longitudinal thermal profiles of nine reaches in the lower Yakima River were surveyed at ambient river velocity during summer 2018 when surface-water temperatures were near their annual maximum and the difference between surface-water and groundwater temperatures was greatest. The profiles were compared to previously published profiles of the same reaches measured in 2001, 2002, 2008, and 2009, and analyzed in the context of hydrologic, geomorphic, and hydrogeologic conditions that may create and maintain cold-water inputs to the river. Cold-water anomalies that departed from expected diurnal increases in water temperature were measured in all nine study reaches and were attributed to diffuse groundwater discharge through the streambed, discrete groundwater discharge at seeps and springs, and cold-water tributaries entering the river. Some cold-water anomalies were measured during repeated surveys in different years, whereas other cold-water anomalies did not persist across surveys. Additionally, some discrete cold-water anomalies were confined to one side of the channel, but others associated with diffuse groundwater discharge were present across the channel for several river miles. Hydrogeologic conditions including the extent and thickness of aquifers connected to the Yakima River, geomorphic conditions including channel gradient, channel geometry, and floodplain extent, and the location of tributaries, irrigation returns, and other surface-water inputs created the large-scale conditions that facilitate the formation and maintenance of cold-water anomalies. Finer-scale geomorphic features such as side channels, gravel-bar alcoves, deep pools, and other locations, where colder water collected and remained relatively unmixed with upstream surface water, were also important factors in the occurrence and distribution of cold-water anomalies. These hydrogeologic and geomorphic conditions, coupled with the alteration of the Yakima River’s hydrologic regime to support irrigation within the Yakima Valley, contributed to the surveyed distribution of cold-water anomalies within the river.

Washington↗

Sediment and nutrient retention on a reconnected floodplain of an Upper Mississippi River tributary, 2013–2018

The connection of rivers with their floodplains has been greatly reduced in agricultural drainage basins, especially in the Upper Mississippi River Basin. The restriction of the Mississippi River from its floodplain has reduced the sediment trapping and nutrient deposition capabilities of the floodplain, exacerbating water quality problems in the river and in downstream waterbodies. A small part of the Maquoketa River, a tributary to the Upper Mississippi River, was permanently reconnected to its floodplain in 2010 when a levee failure resulted in breaches in two locations. This study quantified the water quality benefits of that reconnection from October 2013 through September 2018. As part of the study, data from groundwater monitoring wells were used to determined hydraulic connectivity and surface-water/groundwater mixing; soil samples were collected in the floodplain to quantify floodplain sediment and nutrient retention potential during postflood and dry, interflood periods; and sensors were placed in the Maquoketa River to quantify total suspended solids, nitrogen, and phosphorus concentrations and loads. The floodplain aquifer in the study area had low hydraulic gradients toward the Maquoketa (mean of 0.017) and Mississippi Rivers (mean of 0.0029) and reducing water-quality conditions (dissolved oxygen less than 1.0 milligram per liter [mg/L] and nitrate less than 0.04 mg/L as nitrogen) capable of denitrification. A specific conductance-based mixing indicated precipitation was the predominate source of groundwater; however, specific conductance-based mixing analysis was unable to distinguish between the river or direct precipitation as the source. The floodplain was fully inundated five times during the study: in June–July 2014, March 2015, January 2017, February 2018, and September 2018. During the March 2015 flood (the only inundation event with sufficient duration to leave quantifiable sediment deposition in the study area), the equivalent of 0.91 percent of the nitrate load and 3.8 percent of the phosphorus load was deposited as sediment on the floodplain. Potential nitrogen losses on the floodplain because of denitrification ranged from 250 kilograms per day (kg/d) as nitrogen in March 2015 to 668 kg/d as nitrogen in October 2014. Potential denitrification rates indicate that when the soil is inundated, inorganic nitrogen present in the soil and in the water column is rapidly denitrified. Soil phosphorus measurements indicated that floodplain soils contain a mean of 365 milligrams per kilogram as phosphorus but still have the capacity to remove phosphorus from flood waters of the Maquoketa River depending on the surface water phosphorus concentration. Results from this study indicate that restoration of even small river-floodplain connections can improve water quality in the Upper Mississippi River.

Iowa↗

Modeling the water-quality effects to the Klamath River from recirculation in drains and canals, Oregon and California, 2006–15

The potential recirculation of Klamath Strait Drain (hereafter called by its local name, “Klamath Straits Drain”) water into Ady Canal to reduce the drain discharge of high nutrient loads into the Klamath River was assessed by the U.S. Geological Survey for the Bureau of Reclamation. To study the feasibility of recirculation, this investigation evaluated three recirculation scenarios over a 10-year period from 2006 to 2015, as a series of 1-year model simulations. A combination of two existing hydrodynamic, water-temperature, and water-quality models (CE-QUAL-W2) were used, including (1) the Link-Keno reach of the Klamath River, using Klamath Straits Drain as a tributary and for calendar years 2006–11, and (2) the same Link-Keno model used for calendar years 2012–15 in combination with an independent Klamath Straits Drain model from 2012 to 2015. Model simulations using the water-quality models were configured for the base case conditions and three different sets of recirculation scenarios: the maximum year-round recirculation without limits (scenario 1), limited year-round recirculation fixed by the current pipe flow configuration (scenario 2), and limited seasonal recirculation (May–September) also fixed by the current pipe flow configuration (scenario 3). In the base case, estimates of annual average daily total nitrogen loads and daily total phosphorus loads exported to the Klamath River from the Klamath Straits Drain were as much as 3,060 and 457 pounds per day (lbs/day), respectively. Currently (2023), the Total Maximum Daily Loads allocations for the Klamath Straits Drain are 21 and 268 lbs/day for total phosphorus and total nitrogen, respectively, so these maximum estimates exceed the current Total Maximum Daily Loads by greater than an order of magnitude. With scenario 1, load reductions occurred year-round for all constituents evaluated (total nitrogen, total phosphorus, 5-day biochemical oxygen demand [BOD5], 5-day carbonaceous biochemical oxygen demand) for the Klamath Straits Drain discharging to the Klamath River. Scenario 2 also had large reductions in total nitrogen, total phosphorus, and BOD5 loads. Substantial reductions did occur for scenario 3 but were constrained to only the active recirculation period from May through September. Despite the restricted period, the average reductions in the annual average daily load for total phosphorus and total nitrogen were 32.1 percent and 26.5 percent, respectively. The Ady Canal diverts high nutrient loads from the Klamath River, so the loading tradeoffs to the Klamath River between no recirculation and the recirculation scenarios were calculated. On an annual basis, the overall net balance between the Klamath Straits Drain and Ady Canal resulted in more total nitrogen and total phosphorus load reductions to the Klamath River for the three recirculation scenarios than the base case, for most years. In contrast, the net balance for BOD5 loads was higher to the Klamath River for the three recirculation scenarios than the base case, for most years. With the recirculation scenarios, the optimal recirculation periods to benefit Ady Canal, Klamath River, and Klamath Straits Drain did not always coincide. Recirculation would be most effective at reducing loads toward the Klamath Straits Drain Total Maximum Daily Load allocations in the spring (March–May) of each year. However, recirculation during these months would also increase salinity in the Ady Canal. In summer, recirculation would reduce Klamath Straits Drain loads toward the Total Maximum Daily Load allocations, though recirculation could decrease Klamath River water quality mostly because of decreased withdrawals of Klamath River water by the Ady Canal. Scenario 3 avoided recirculation into Ady Canal in the early spring months when salinity concerns would be the highest, while still decreasing nutrient loads exported from the Klamath Straits Drain to the Klamath River in the summer months.

California, Oregon↗

Suspended sediment and trace element transport in the Big River downstream from the Old Lead Belt in southeastern Missouri, 2018–21

Lead Belt, an area of major lead mining from the 1860s until 1972 where more than 8.5 million tons of lead were mined. After active mining ceased, the effects of mining activities persisted in the Big River system because of large mine waste pile erosion, and floodplain sediment and streambank contamination along several tributaries and the main stem of the Big River. Lead-contaminated streambed and floodplain sediments extend more than 90 miles from the Old Lead Belt to the confluence of the Big River with the Meramec River. The waste piles and mine-waste contaminated streambed and floodplain sediments have been sources of high concentrations of several trace elements, primarily cadmium, lead, and zinc. The U.S. Environmental Protection Agency Region 7 has made several efforts to prevent further erosion of contaminated sediments into the Big River including the capping of major mine waste piles, reclaiming sediment deposits along the floodplains, and monitoring soil conditions of croplands and residential properties. A cooperative effort began in 2011 between the U.S. Geological Survey and the U.S. Environmental Protection Agency Region 7 to characterize suspended sediment quantity and quality in the Big River downstream from the Old Lead Belt as reclamation activities in the drainage basin progressed. The study was completed in two phases, and each phase included continuous stage, turbidity, and water temperature monitoring at the Big River below Bonne Terre, Missouri, streamgage and sampling station. Periodic suspended sediment samples also were collected manually (discrete samples) during base flow and selected stormflow events. Continuous streamflow, turbidity, and discrete suspended sediment data were used to develop regression models to compute daily suspended sediment concentrations and loads. During both phases, the discrete stormflow event samples were also evaluated to determine particle size distribution and concentrations of select trace elements. Phase one was completed from October 2011 through September 2013, and phase two, which is the primary focus of this report, was completed from October 2018 through September 2021. Phase two also included time-integrated suspended sediment samples collected using passive samplers. Discrete samples (collected during stormflow events) and passive samples were analyzed for concentrations of barium, cadmium, lead, and zinc in two sediment size fractions (when possible) to estimate trace element loads. Suspended sediment concentrations and loads and select trace element concentration results computed during phase one were compared to those computed during phase two to identify trends in the Big River Basin during the full study period. The concentrations of cadmium, lead, and zinc in nearly all discrete stormflow event suspended sediment samples and passive suspended sediment samples exceeded the threshold effect concentrations and the probable effect concentrations, which are two sediment quality guidelines. Most samples also exceeded the toxic effect threshold, the level at which sediment is considered to be heavily contaminated and problematic for sediment-dwelling organisms. Bulk cadmium concentrations (median of 7.90 milligrams per kilogram [mg/kg]) exceeded the toxic effect threshold (3.0 mg/kg) in 17 discrete stormflow event samples, and bulk lead concentrations (median of 1,070 mg/kg) exceeded the toxic effect threshold (170 mg/kg) in all 18 discrete stormflow event samples. Bulk zinc concentrations (median of 500 mg/kg) exceeded the toxic effect threshold (540 mg/kg) in eight discrete stormflow event samples. Bulk concentrations of these trace elements in passive suspended sediment samples were slightly greater, with concentrations of cadmium (median of 14.0 mg/kg) and lead (median of 1,860 mg/kg) exceeding the toxic effect threshold in all 18 samples. Bulk concentrations of zinc (median of 733 mg/kg) exceeded the toxic effect threshold in 15 passive samples. Compared to phase one (water years 2012–13), phase two (water years 2019–21) concentrations of lead and cadmium in the fine fraction of discrete suspended sediment samples collected at Big River below Bonne Terre were statistically similar; concentrations of barium and zinc were statistically smaller in samples collected during phase two (water years 2018–21). Sediment quality data from passive samples and daily mean suspended sediment loads from the regression model were used to calculate annual oads of barium, cadmium, lead, and zinc at the Bonne Terre streamgage. Water year 2019 had the largest loads of barium, cadmium, lead, and zinc (58.6, 1.43, 194, and 76.5 tons, respectively). The total loads of barium, cadmium, lead, and zinc for phase two (water years 2019–21) were 149, 4.00, 520, and 213 tons, respectively. Less than 5 percent of the total lead load calculated for the study period was transported when daily mean streamflow was less than 455 cubic feet per second, which is the approximate flow at which the passive samplers were inundated and began sampling. This highlights that most of the lead load is transported during stormflow events and the effectiveness of using passive samplers for ongoing monitoring of the Big River. Annual suspended sediment loads at the Bonne Terre streamgage computed using the regression model were 113,000 tons in water year 2019, 83,400 tons in water year 2020, and 96,500 tons in water year 2021. The event-based suspended sediment loads for the eight sampled stormflow events ranged from 45.3 to 32,500 tons. Although only a portion of all stormflow events during phase two were sampled, the loads accounted for during these eight stormflow events represented approximately 30.9 percent of the total suspended sediment load calculated for the study period, confirming that a large part of suspended sediments continue to be transported in the Big River during stormflow events. Event-based loads of barium, cadmium, lead, and zinc were greatest during the stormflow events sampled in January 2020 (event 4) and March 2021 (event 8). Event-based loads calculated for event 4 for barium, cadmium, lead, and zinc were 17.1, 0.206, 27.2, and 14.5 tons, respectively. During event 8, an estimated 15.6 tons of barium, 0.239 tons of cadmium, 34.0 tons of lead, and 13.6 tons of zinc were transported in suspended sediments. The continued high concentrations of lead in suspended sediments in the Big River, despite reclamation activities, is likely because of the continual transport from streambed and stream banks of lead-enriched sediment, which remain in the system from historical mining activities.

Missouri↗

Fluvial sediment dynamics in the Shoshone River and tributaries around Willwood Dam, Park County, Wyoming

Sedimentation affects many of the aging reservoirs in the United States. Dams and water diversions from rivers have been central elements of infrastructure supporting agricultural irrigation in the arid and semiarid regions of the Western United States for more than a century. The Willwood Irrigation District diversion dam (hereafter referred to as “Willwood Dam”) in Park County, Wyoming, is approximately 12 miles northeast of Cody, Wyo.; has a structural height of 70 feet; and impounds the Shoshone River for diversion into the Willwood Canal. Willwood Dam is part of a larger irrigation scheme supported by water storage in the much larger Buffalo Bill Dam, which is approximately 20 miles upstream. In October 2016, renovation construction activities at Willwood Dam and the Willwood Canal caused an unplanned evacuation of nearly 96,000 cubic yards of fine sediment. The fine sediment release in 2016 raised concerns that ongoing sediment management at Willwood Dam could impose limits on the long-term health of the aquatic ecosystem and fish populations. The U.S. Geological Survey, in cooperation with Wyoming Department of Environmental Quality and Willwood Work Groups 2 and 3, initiated an investigation of the dynamics of sediment transport in the Shoshone River and selected tributaries between Buffalo Bill Dam and Willwood Dam. The goal of the study was to quantify sediment transport into and out of Willwood Dam on an annual, seasonal, and event basis to better understand the relative quantities of sediment coming from natural sources and human activities on the landscape. The study ran from March 2019 through October 2021 and used observations of streamflow, turbidity, and acoustic backscatter collected at streamgages upstream and downstream from Willwood Dam to quantify suspended-sediment loads into and out of the dam during irrigation and fallow seasons, precipitation-runoff events, and deliberate sediment releases. Each tributary’s relative contribution to the sediment load upstream from Willwood Dam was examined using discrete measurements of suspended-sediment concentration and bedload during irrigation and fallow seasons, precipitation events, and stable conditions. Analysis of daily precipitation and temperature data indicated that conditions in the study area during the 2019 agricultural year were wetter and colder than period of record normal, and drier and near normal temperatures for the 2020 and 2021 agricultural years. Not all sediment load records between 2019 and 2021 are complete because of rejected observations (outliers), instrument failures or fouling, and instrument removal for calibrations. Statistical modeling of suspended-sediment concentration using paired values of turbidity and acoustic backscatter produced four models that, after refinement, had coefficients of determination indicating that more than 84 percent of the variance was explained by either turbidity or acoustic backscatter. A system of rules was developed to select the model predictions based on the seasonal operations of Willwood Dam, assumptions about the grain sizes mobilized during these operations, and assumed accuracy of the models at the downstream streamgage (Shoshone River below Willwood Dam, near Ralston, Wyo. [streamgage 06284010]) under different operational conditions. The sediment budget between upstream and downstream estimates of loads was interpreted using the mean predicted values bound by their respective model prediction intervals. When mean predicted loads of one streamgage were contained in the prediction intervals of the other streamgage, and vice-versa, difference in the sediment budget were interpreted as “indeterminate.” Modeled sediment load balances demonstrated the depositional and erosional behaviors expected from the conceptual model of dam operations whereby sediment tends to accumulate during irrigation seasons when the dam is spilling over the top, and sediment tends to evacuate during the fallow seasons when it is flowing through the sluice gates at the base of the dam. The sediment load calculations using the rules-based model criteria indicated that between 14,200 and 380,000 tons of suspended sediment moved through the Shoshone River around Willwood Dam during the irrigation seasons of 2019, 2020, and 2021; 380,000 tons of suspended sediment were transported during the cool, wet year of 2019, and 14,200 tons of suspended sediment were transported in 2020, which was relatively dry. During fallow seasons 2019, 2020, and 2021, which had fewer complete records, between 1,140 and 106,000 tons of suspended sediment was estimated to have moved through the river. For all seasons except fallow season 2022, the models estimated that more sediment was released from the dam than entered the dam, but the modeled mean loads at each streamgage were nearly always within the prediction intervals of each other, making the sediment balance indeterminant. Examination of suspended-sediment loads during irrigation seasons indicated that between 65 and 85 percent of fine sediment was transported during annual high flows and storm events, with the remainder transported during steady, lower streamflows. Examination of suspended loads during fallow seasons indicated that deliberate sediment releases through Willwood Dam accounted for between 39 and 67 percent of the total sediment moved during the fallow seasons. Deliberate sediment releases from Willwood Dam had estimated net exports of between 1,360 and 22,400 tons. Between August 2017 and July 2023, suspended-sediment concentration and bedload sediment samples were collected from 9 tributaries to the Shoshone River during 137 sampling events, including stable and precipitation-runoff conditions. During irrigation season precipitation events, the mean total sediment yields ranged from 0.33 to 9.51 tons per day per square mile; during fallow season precipitation events, the mean total yields ranged from 0.04 to 0.95 ton per day per square mile. The mean total sediment yield per unit area across all samples at each tributary site ranged from 0.26 to 3.08 tons per day per square mile. Bedload was a minor fraction of the total load, constituting a mean of 4 percent across all samples; 3 and 6 percent for events and nonevents, respectively, during irrigation season; and 3 and 1 percent for events and nonevents, respectively, during the fallow season. With the exception of one tributary, Dry Creek, these mean yield values were within the range of watershed-scale background sediment yield values estimated from reservoir surveys and previous suspended-sediment studies. Imagery from irrigation seasons 2012, 2015, 2017, 2019, and 2022 was used to determine the planimetric backwater extent of the pool area in the Shoshone River behind Willwood Dam to identify any changes in sediment storage. Active river channel widths in the Shoshone River upstream from Willwood Dam were all similar between years except 2015, which was determined to be statistically different from all other years. Bathymetric data taken in the pool behind Willwood Dam during three different surveys between November 2017 and April 2022 indicated no statistically significant differences in bed elevations between the years. Results from the planimetric and bathymetric survey data provide multiple lines of evidence indicating that sediment did not accumulate behind the dam within the error of the methods used. Examination of how precipitation affects sediment transport in the Shoshone River upstream from Willwood Dam indicated that accumulated rainfall from the natural runoff events captured during the study period varied from a trace to as much as 4.26 inches, with associated predicted suspended-sediment loads varying from 112 to 232,000 tons of suspended sediment. The behavior of the sediment loads relative to accumulated precipitation did not appear to change depending on irrigation or fallow season. A model of suspended-sediment concentrations relative to the 2-day accumulated precipitation indicated that suspended-sediment concentrations in the Shoshone River upstream from Willwood Dam increased exponentially for accumulations of 0.3 inch or more; such storms accounted for 10 percent or less of precipitation events observed during the 1981 to 2018 period of record. The gaps in records, precision of the instrumentation, and large variation in grain sizes in suspended-sediment mixtures downstream from the dam made closing the sediment budgets for most seasons unattainable. The biggest recent change in sediment storage measured using the planimetric area of deposits behind Willwood Dam took place between 2015 and 2017. The main event between these two measurements was the installation of new Willwood Canal gates in October 2016, which resulted in the large unplanned sediment release. Because the sediment budgets were nearly always indeterminate and the planimetric and bathymetric data indicated little change in the bed and bank material, it is likely that the change in sediment storage behind the dam during the study period was small relative to the precision of the statistical models and other uncertainties. This body of evidence suggests that, averaged during the 3-year study period, no major changes in storage took place, and that the current operations may be keeping storage at near-equilibrium. This condition could have been initiated because the middle sluice gate has now been operational since 2014, and the sediment release in October 2016 evacuated a large amount of legacy sediment from storage. Although the uncertainties are large, sluicing events allow for controlled releases of sediment that contributed to the near equilibrium conditions observed over an annual basis during this study.

Wyoming↗

Dissolved cadmium, zinc, and lead loads from ground-water seepage into the South Fork Coeur d'Alene River system, northern Idaho, 1999

The valley of the South Fork Coeur d’Alene River and some of its tributaries have been heavily impacted by the dispersion of metal-enriched materials from the Coeur d’Alene mining district since 1884. The valley floor, including the unconsolidated valley-fill/flood-plain aquifers, is a major holding area for mine tailings. The U.S. Geological Survey, in cooperation with the U.S. Environmental Protection Agency, characterized groundwater and surface-water relations for parts of the South Fork Coeur d’Alene River Basin and quantified the loading of dissolved metals into the South Fork Coeur d’Alene River system from groundwater seepage. This information can be used to determine the effects of dissolved metal from ground-water seepage on the river system and to evaluate the necessity and feasibility of remediation along gaining reaches. This study defines a field approach that can be repeated during and after the implementation of remediation solutions to measure the effectiveness of these efforts in reducing loading to streams. The study area includes three reaches along the South Fork Coeur d’Alene River valley in the Coeur d’Alene mining district in central Shoshone County, northern Idaho: a 3.3-mile reach of Canyon Creek at Woodland Park, a 4.8-mile reach of the South Fork Coeur d’Alene River near Osburn, and a 6.5-mile reach of the South Fork Coeur d’Alene River near Kellogg and Smelterville. Seepage studies were conducted during July 27–29; September 17–19; and October 15–17, 1999. Each seepage study was conducted over a 3-day period, during which each station was measured on a daily basis for streamflow, and waterquality samples were collected. The consecutiveday approach allowed for an evaluation of variability in streamflow gains and losses and metal loading that resulted from changing hydrologic conditions. During the July, September, and October seepage studies, ground-water seepage was the predominant source for gains in dissolved cadmium and zinc loads in the three study reaches, whereas tributary inflow loads were a minor source. The overall average net gain in dissolved zinc load from ground-water seepage into the South Fork Coeur d’Alene River near Kellogg and Smelterville was about 730 pounds per day, compared with the net gains in Canyon Creek at Woodland Park and the South Fork Coeur d’Alene River near Osburn, which were roughly similar at 150 and 218 pounds per day, respectively. The net gain in dissolved cadmium load from ground-water seepage into the three river reaches was about two orders of magnitude less than the gain in dissolved zinc. On the South Fork Coeur d’Alene River study reaches near Osburn and near Kellogg and Smelterville, no pattern associated with an increase or decrease in dissolved lead load along gaining or losing subreaches was recognizable. Canyon Creek at Woodland Park was the only study reach where ground-water seepage contributed appreciably to the dissolved lead load; the average net gain was 1.5 pounds per day. The average dissolved lead loads leaving South Fork Coeur d’Alene River study reaches (corrected for tributary inflow along the study reaches) near Osburn and near Kellogg and Smelterville were 1.4 and 0.8 pounds per day less, respectively, than the loads entering the study reaches. The decrease in dissolved lead could be the result of lead adsorbing onto organic and inorganic sediment surfaces and (or) coprecipitating with iron and manganese oxides. These forms of lead likely will be resuspended into the water column at high flows.

Idaho↗

Pesticides in surface water in the lower Illinois River basin, 1996-98

Surface-water quality samples were collected from April 1996 to September 1998 from eight locations in the Lower Illinois River Basin, a study unit of the U.S. Geological Survey?s National Water-Quality Assessment program. The study area is approximately 15,600 square miles and encompasses most of central and western Illinois. The dominant land use is agricultural and most land is used for the production of corn and soybeans. About 6.9 million acres of corn and soybeans are planted annually in the lower Illinois River Basin. Conservation tillage, defined as mulch-till and no-till, is used on about 40 percent of the cropland in the study area, similar to the statewide average. Nearly 90 percent of the samples for pesticide analyses were collected at four sites: the Illinois River at Ottawa, the Illinois River at Valley City, the La Moine River at Colmar, and the Sangamon River at Monticello. Two hundred fifty-eight samples were collected and analyzed for various herbicides, insecticides, and herbicide transformation products (also referred to as degradates). Thirty-one pesticides were detected at concentrations above their respective method detection limit: 23 herbicides and 8 insecticides. An additional set of 34 samples was collected in the summer of 1998 for the analysis of herbicide transformation products. Nine herbicide transformation products were detected, all belonging to the chloroacetanilide or the triazine chemical class. Two herbicides, atrazine and cyanazine, exceeded the associated human health drinking-water criteria and the aquatic health-criteria. Atrazine was detected in all samples. Sixty percent of the samples (48 of 80) collected in the months of May and June had atrazine concentrations that exceeded the clean drinking- water standard of 3 micrograms per liter (mg/L). The average atrazine concentration in the May to June samples was about 7.0 mg/L. The maximum atrazine concentrations were 110 mg/L in the La Moine River at Colmar and 32 mg/L in the Sangamon River at Monticello. The maximum atrazine concentration in the lower Illinois River was 20 mg/L, measured at Valley City, although most of the relatively elevated concentrations in the Illinois River sites were in the range from 5 to 8 mg/L. The concentrations of the herbicide cyanazine exceeded the health advisory guideline of 1 mg/L in about 19 percent (15 of 80) of the May to June samples. The pesticides chlorpyrifos, diazinon, metolachlor, and 2,4-D exceeded aquatic health guidelines at various times from May to August. Three dominant factors that affect the presence of pesticides in streams are identified: the pesticide usage, the time-of-year (or season), and the flow condition. The pesticides with the highest usage--atrazine, metolachlor, cyanazine, and acetochlor--generally were the pesticides detected most frequently and at the highest concentrations. Notable exceptions to this general observation are alachlor and simazine, which did not have high usage but were detected frequently. The elevated pesticide concentrations were most affected by seasonality--most of these elevated concentrations were observed across all flow conditions during May to June. Flow conditions also affect pesticide concentrations, but not as much as seasonality. The maximum pesticide loads were observed between March and July on the Illinois River. The net contribution of pesticides applied in the study area to net increases in load indicates that only about 1-2 percent of the pesticides applied exit the basin through the Illinois River at Valley City. The chloroacetanilide-class transformation products observed in samples collected in summer 1998 persistently contained elevated concentrations relative to the associated parent pesticide compound at all locations and for all streamflow conditions. The concentration of the transformation product metolachlor ethane sulfonic acid (ESA) usually was about 10 times higher than the parent compound in the mainstem of the lower

Water-Resources Investigations Report↗

Channel stability and water quality of the Alagnak River, southwestern Alaska

The Alagnak River, a National Wild River located in southwestern Alaska, drains an area of 3,600 square kilometers and is used for recreational and subsistence activities, primarily angling, camping, rafting, and hunting by visitors and seasonal residents, and for commercial guiding by several lodges. Increases in visitor use in the 1990s included an increase in the use of high-horsepower motorboats on the river, primarily for angling, and raised concerns regarding human impacts on water quality. Downstream from its confluence with the Nonvianuk River at river kilometer (RK) 93, the Alagnak River is formed in glacial drift and outwash with a single, low bedrock outcrop. Analysis of aerial photography from 1951, 1982, and 2001 shows that the river's multiple channels from RK 57 to 93 have been relatively stable. In contrast, long reaches of multiple channels from RK 35 to 57 changed substantially between 1951 and 1982, creating a new complex of channels. Downstream from RK 35, channel changes in the past 50 years consist largely of minor meander migration. Analysis of water samples collected during this study at RK 21, 46, and 93 and in the Alagnak and Nonvianuk Rivers at the outlets of the lakes that form their source shows that the Alagnak River is a nutrient-poor, calcium-bicarbonate water with low suspended-sediment concentrations. Water chemistry changes little over time or in a downstream direction. Weak patterns over time include high late May/early June concentrations of some nutrients, carbon, and iron. Weak patterns over distance include downstream increases in iron, manganese, and phosphorous. No pervasive human impacts on Alagnak River water chemistry were detected. Local effects that could be diluted within a kilometer downstream of the source were not detectable by this study. Data collected at three continuously recording wake gaging stations at RK 21, 46, and 93 showed that 1999-2000 motorboat use was heaviest in the lower reaches of the river, moderate in the middle reaches, and very light in the upper reaches. Maximum boat use was 137, 40, and 4 wakes per day at RK 21, 46, and 93, respectively. The mean height of the maximum wave generated in each wake was about 0.15 m (meters) at all three gaging stations. Bank erosion monitoring at 14 sites between RK 21 and 93 quantified erosion rates ranging from 0 to 1.1 m/yr (meters per year). Erodibility (based on grain-size analysis) increases in a downstream direction, as do measured erosion rates. Alagnak River banks are noncohesive and erode by grain-by-grain removal of sediment in an alternating pattern of water-driven erosion and gravitydriven erosion. Periodic surveys at bank erosion monitoring sites detected the development of a shallow underwater shelf formed by the action of wind waves and boat wakes at several sites. This shelf contains sediment eroded from the bank and redeposited adjacent to the bank; the shelf reformed as water levels changed but maintained the same wave-generated form throughout much of the season. Measurements of bank erosion processes, particularly the development of a wave-generated shelf, and visual observations suggest that boat wakes increase bank erosion rates, especially at high, exposed banks. Analysis of aerial photography and other assessments of bank erosion processes indicate that this increase in erosion rates has not altered the mechanisms of channel change, which in the past 50 years have included complex, compound channel changes and meander migration.

Water-Resources Investigations Report↗

Hydrologic conditions in the Bill Williams River National Wildlife Refuge and Planet Valley, Arizona, 2000

During a period of sustained base-flow conditions in the Bill Williams River below Alamo Dam in west central Arizona from March to July 2000, the channel of the river through Planet Valley was dry, and the water table sloped almost due west parallel to the main slope of the flood plain. Water from the river infiltrated into the channel bottom at the head of Planet Valley, moved downgradient in the subsurface, and reappeared in the channel about 0.3 mile downstream from the east boundary of the Bill Williams River National Wildlife Refuge. A river aquifer in hydraulic connection with the Bill Williams River was mapped from a point 6.3 miles upstream from Highway 95 to the upstream end of Planet Valley. Formations that make up the river aquifer in Planet Valley are younger alluvium, older alluviums, and fanglomerate. Total thickness of the river aquifer probably is less than 200 feet in the bedrock canyons to as much as 1,035 feet in Planet Valley. The purpose of this study was to investigate the current hydrologic conditions along the Bill Williams River, which included an inventory of wells within the river aquifer of the Colorado River and in Planet Valley, and to determine the configuration of the water table. A map shows the elevation and configuration of the water table from the east end of Planet Valley to the confluence of the Bill Williams River with Lake Havasu.

Arizona↗

Microbiological Water Quality in Relation to Water-Contact Recreation, Cuyahoga River, Cuyahoga Valley National Park, Ohio, 2000 and 2002

The microbiological water quality of a 23-mile segment of the Cuyahoga River within the Cuyahoga Valley National Park was examined in this study. This segment of the river receives discharges of contaminated water from stormwater, combined-sewer overflows, and incompletely disinfected wastewater. Frequent exceedances of Ohio microbiological water-quality standards result in a health risk to the public who use the river for water-contact recreation. Water samples were collected during the recreational season of May through October at four sites on the Cuyahoga River in 2000, at three sites on the river in 2002, and from the effluent of the Akron Water Pollution Control Station (WPCS) both years. The samples were collected over a similar range in streamflow in 2000 and 2002. Samples were analyzed for physical and chemical constituents, as well as the following microbiological indicators and pathogenic organisms: Escherichia coli (E. coli), Salmonella, F-specific and somatic coliphage, enterovirus, infectious enterovirus, hepatitis A virus, Clostridium perfringens (C. perfringens), Cryptosporidium, and Giardia. The relations of the microorganisms to each other and to selected water-quality measures were examined. All microorganisms analyzed for, except Cryptosporidium, were detected at least once at each sampling site. Concentrations of E. coli exceeded the Ohio primary-contact recreational standard (298 colonies per 100 milliliters) in approximately 87 percent of the river samples and generally were higher in the river samples than in the effluent samples. C. perfringens concentrations were positively and significantly correlated with E. coli concentrations in the river samples and generally were higher in the effluent samples than in the river samples. Several of the river samples that met the Ohio E. coli secondary-contact recreational standard (576 colonies per 100 milliliters) had detections of enterovirus, infectious enterovirus, hepatitis A virus, and Salmonella, indicating that there are still risks even when the E. coli standard is not exceeded. River samples in which the secondary-contact recreational standard for E. coli was exceeded showed a higher percentage of the co-occurrence of pathogenic organisms than samples that met the standard. This indicates that in this study area, E. coli is a useful indicator of human health risk. Detections of hepatitis A virus tended to be associated with higher median concentrations of somatic coliphage, F-specific coliphage, and infectious enterovirus. In addition, geometric mean C. perfringens concentrations tended to be higher in samples where hepatitis A virus was present than in samples where hepatitis A virus was absent. Hepatitis A virus was not detected in samples collected upstream from the Akron WPCS; all downstream detections had coincident detections in the Akron WPCS effluent, suggesting that Akron WPCS was a principal source of hepatitis A virus at the downstream sites. Geometric mean concentrations of E. coli were calculated on the basis of analytical results from at least five samples collected at each river site during May, July, and September of 2000. In each case, the Ohio geometric-mean primary-contact recreational standard of 126 col/100 mL was exceeded. E. coli concentrations were significantly correlated with streamflow and increased with streamflow at sites upstream and downstream from the Akron WPCS. This indicates that E. coli loads from sources upstream from the Akron WPCS have the potential to appreciably influence the frequency of attainment of recreational water-quality standards at downstream locations.

Water-Resources Investigations Report↗

Water-quality assessment of part of the Upper Mississippi River Basin, Minnesota and Wisconsin: Trace elements in streambed sediment and fish livers, 1995-96

Trace elements were analyzed in streambed sediment and fish livers in part of the Upper Mississippi River Basin as part of the U.S. Geological Survey’s National Water-Quality Assessment Program. The purpose of this report was to describe the occurrence and distribution of trace elements, describe the relations of concentrations measured to natural and anthropogenic factors, and describe any relation between concentrations in streambed sediment and fish livers. The study unit included the part of the Upper Mississippi River Basin from the river’s source in northern Minnesota to the outlet of Lake Pepin, a natural lake on the river located near Red Wing, Minnesota. Streambed sediment samples were collected from 27 sites located throughout the study unit, and fish were obtained from 25 sites. The occurrence and distribution of trace elements in streambed sediment were related to land use and the composition of surficial glacial deposits covering the study unit. Concentrations of antimony, arsenic, cadmium, copper, lead, mercury, nickel, and zinc in streambed sediment were primarily related to urban land use. Concentrations of these elements generally were greatest in streambed sediment collected at sites within or near urban areas in the study unit. The greatest concentrations of most of these elements were measured in streambed sediment obtained from Shingle Creek. Lead concentrations in streambed sediment Shingle Creek increased in the downstream direction. This pattern probably reflects the past use of leaded gasoline, pesticides, or paints. Cadmium concentrations in sediment from the Mississippi River were greatest at Nininger, Minnesota and in Lake Pepin. This pattern suggested that inputs of cadmium into the river were from the TCMA. Arsenic concentrations were greatest in streambed sediment collected from Cedar Creek, Shingle Creek, and the Vermillion River. Increased arsenic and iron concentrations in sediment from Cedar Creek, the Vermillion River, and the most upstream site on Shingle Creek suggested a local source of sulfide minerals or preferential sorption of arsenic to streambed sediment. The greatest concentrations of mercury were measured in streambed sediment collected from the Mississippi River at Grand Rapids and Minneapolis, Minnesota; Shingle Creek at 46th Street in Minneapolis, Minnesota; the Namekagon River above Spring Lake Creek near Hayward, Wisconsin; the St. Croix River at Hudson, Wisconsin; and the Vermillion River near Empire, Minnesota. In fish livers, all of the trace elements analyzed were detected except antimony, beryllium, cobalt, and uranium. Trace element concentrations in fish livers generally did not show any pronounced patterns. Ranges for concentrations of arsenic, cadmium, chromium, copper, lead, mercury, nickel, selenium, and zinc were similar to those measured in 20 other NAWQA studies across the United States. Cadmium concentrations in fish livers were moderately correlated to fish length and weight. There were no relations between trace element concentrations in fish livers and streambed sediment.

Minnesota, Wisconsin↗

Areal and temporal variations in the quality of surface water in hydrologic accounting unit 120301, Upper Trinity River basin, Texas

Hydrologic Accounting Unit 120301 is located in north-central Texas and includes that part of the Trinity River basin upstream from the National Stream Quality Accounting Network station 08062700, Trinity River at Trinidad, Texas. Normal annual precipitation ranges from about 28 inches in the western part of the basin to almost 40 inches in the eastern part. The population of the upper Trinity River basin was nearly 3 million in 1980. Total water use in 1980 was approximately 826,000 acre-feet, of which 90 percent was obtained from surface-water resources. Mean discharges for most stations in the study area during the 1973-82 water years were significantly larger than mean discharges for the period of record. Mean discharges throughout most of the study area during the 1982 water year were more than 300 percent of the long-term mean flow. Water in the upper Trinity River basin upstream of the Dallas-Fort Worth metroplex is generally a calcium bicarbonate type water. In the West Fork Trinity River downstream from Fort Worth and the main stem of the Trinity River from Dallas to Trinidad, the water is a mixed sodium calcium bicarbonate type water. Average dissolved-solids concentrations during the study period ranged from 174 milligrams per liter in the Elm Fork Trinity River near Lewisville to 682 milligrams per liter in Mountain Creek near Cedar Hill. Discharge-weighted average dissolved-solids concentrations during 1973-82 water years ranged from 165 milligrams per liter in the Elm Fork Trinity River near Lewisville to 416 milligrams per liter at Mountain Creek near Cedar Hill. Daily dissolved-solids loads increased from 225 tons at West Fork Trinity River at Beach Street, Fort Worth, to 2,410 tons in the Trinity River at Trinidad. In the 450 square miles of intervening drainage area between West Fork Trinity River at Beach Street, Fort Worth, and West Fork Trinity River at Grand Prairie, the average daily dissolved-solids load increased by 305 tons. Upstream of the municipal waste effluents in the Dallas-Fort Worth metroplex, average dissolved-oxygen concentrations generally exceed 7.0 milligrams per liter, average dissolved-oxygen percent-saturation values generally exceed 70 percent, and average biochemical oxygen demand concentrations generally were less than 4.0 milligrams per liter. Downstream of the municipal waste effluents, average dissolved-oxygen concentrations generally did not exceed 5.0 milligrams per liter, average dissolved-oxygen percent-saturation values generally were less than 50 percent, and average biochemical oxygen demand concentrations generally were greater than 12.0 milligrams per liter.

Water-Resources Investigations Report↗

Estimates of average annual tributary inflow to the lower Colorado River, Hoover Dam to Mexico

Estimates of tributary inflow by basin or area and by surface water or groundwater are presented in this report and itemized by subreaches in tabular form. Total estimated average annual tributary inflow to the Colorado River between Hoover Dam and Mexico, excluding the measured tributaries, is 96,000 acre-ft or about 1% of the 7.5 million acre-ft/yr of Colorado River water apportioned to the States in the lower Colorado River basin. About 62% of the tributary inflow originates in Arizona, 30% in California, and 8% in Nevada. Tributary inflow is a small component in the water budget for the river. Most of the quantities of unmeasured tributary inflow were estimated in previous studies and were based on mean annual precipitation for 1931-60. Because mean annual precipitation for 1951-80 did not differ significantly from that of 1931-60, these tributary inflow estimates are assumed to be valid for use in 1984. Measured average annual runoff per unit drainage area on the Bill Williams River has remained the same. Surface water inflow from unmeasured tributaries is infrequent and is not captured in surface reservoirs in any of the States; it flows to the Colorado River gaging stations. Estimates of groundwater inflow to the Colorad River valley. Average annual runoff can be used in a water budget; although in wet years, runoff may be large enough to affect the calculation of consumptive use and to be estimated from hydrographs for the Colorado River valley are based on groundwater recharge estimates in the bordering areas, which have not significantly changed through time. In most areas adjacent to the Colorado River valley, groundwater pumpage is small and pumping has not significantly affected the quantity of groundwater discharged to the Colorado River valley. In some areas where groundwater pumpage exceeds the quantity of groundwater discharge and water levels have declined, the quantity of discharge probably has decreased and groundwater inflow to the Colorado River valley will eventually be reduced if not stopped completely. Groundwater discharged at springs below Hoover Dam is unused and flows directly to the Colorado River. (Lantz-PTT)

Water-Resources Investigations Report↗