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At least 1,153 records · Page 64Linked to original sources
USGS2001

Relations among geology, physiography, land use, and stream habitat conditions in the Buffalo and Current River systems, Missouri and Arkansas

This study investigated links between drainage-basin characteristics and stream habitat conditions in the Buffalo National River, Arkansas and the Ozark National Scenic Riverways, Missouri. It was designed as an associative study - the two parks were divided into their principle tributary drainage basins and then basin-scale and stream-habitat data sets were gathered and compared between them. Analyses explored the relative influence of different drainage-basin characteristics on stream habitat conditions. They also investigated whether a relation between land use and stream characteristics could be detected after accounting for geologic and physiographic differences among drainage basins. Data were collected for three spatial scales: tributary drainage basins, tributary stream reaches, and main-stem river segments of the Current and Buffalo Rivers. Tributary drainage-basin characteristics were inventoried using a Geographic Information System (GIS) and included aspects of drainage-basin physiography, geology, and land use. Reach-scale habitat surveys measured channel longitudinal and cross-sectional geometry, substrate particle size and embeddedness, and indicators of channel stability. Segment-scale aerial-photo based inventories measured gravel-bar area, an indicator of coarse sediment load, along main-stem rivers. Relations within and among data sets from each spatial scale were investigated using correlation analysis and multiple linear regression. Study basins encompassed physiographically distinct regions of the Ozarks. The Buffalo River system drains parts of the sandstone-dominated Boston Mountains and of the carbonate-dominated Springfield and Salem Plateaus. The Current River system is within the Salem Plateau. Analyses of drainage-basin variables highlighted the importance of these physiographic differences and demonstrated links among geology, physiography, and land-use patterns. Buffalo River tributaries have greater relief, steeper slopes, and more streamside bluffs than the Current River tributaries. Land use patterns in both river systems correlate with physiography - cleared land area is negatively associated with drainage-basin average slope. Both river systems are dominantly forested (0-35 per-cent cleared land), however, the potential for landscape disturbance may be greater in the Buffalo River system where a larger proportion of cleared land occurs on steep slopes (>15 degrees). When all drainage basins are grouped together, reach-scale channel characteristics show the strongest relations with drainage-basin physiography. Bankfull channel geometry and residual pool dimensions are positively correlated with drainage area and topographic relief variables. After accounting for differences in drainage area, channel dimensions in Buffalo River tributaries tend to be larger than in Current River tributaries. This trend is consistent with the flashy runoff and large storm flows that can be generated in rugged, sandstone-dominate terrain. Substrate particle size is also most strongly associated with physiography; particle size is positively correlated with topographic relief variables. When tributaries are subset by river system, relations with geology and land use variables become apparent. Buffalo River tributaries with larger proportions of carbonate bedrock and cleared land area have shallower channels, better-sorted, gravel-rich substrate, and more eroding banks than those with little cleared land and abundant sandstone bedrock. Gravel-bar area on the Buffalo River main stem was also larger within 1-km of carbonate-rich tributary junctions. Because geology and cleared land are themselves correlated, relations with anthropogenic and natural factors could often not be separated. Channel characteristics in the Current River system show stronger associations with physiography than with land use. Channels are shallower and have finer substrates in the less rugged, karst-rich, western basins than in the

Arkansas, Missouri↗
USGS2017

Effectiveness of environmental flows for riparian restoration in arid regions: A tale of four rivers

Environmental flows have become important restoration tools on regulated rivers. However, environmental flows are often constrained by other demands within the river system and thus typically are comprised of smaller water volumes than the natural flows they are meant to replace, which can limit their functional efficacy. We review environmental flow programs aimed at restoring riparian vegetation on four arid zone rivers: the Tarim River in China; the Bill Williams River in Arizona, U.S.; the delta of the Colorado River in Mexico; and the Murrumbidgee River in southern Australia. Our goal is to determine what worked and what did not work to accomplish restoration goals. The lower Tarim River in China formerly formed a “green corridor” across the Taklamakan Desert. The riparian zone deteriorated due to diversion of surface and groundwater for irrigated agriculture. A massive restoration program began in 2000 with release of 1038 million cubic meters of water over the first three years. Groundwater levels rose but the ecological response was less than expected politically, socially and within the scientific community. However, releases continued and by 2015 portions of the original iconic Populus euphratica (Euphrates poplar) forest were reestablished. The natural flow regime of the Bill Williams River was disrupted by construction of a dam in 1968, dramatically reducing peak flows along with associated fluvial processes. As a result, the channel narrowed and riparian vegetation expanded and was comprised largely of an introduced shrub species ( Tamarix spp.). Environmental flow releases including small, managed floods and sustained base flows have been implemented since the mid 1990’s to promote establishment and maintenance of native riparian trees (cottonwoods and willows) and have been successful, although in a “downsized” portion of the valley bottom. Experience from the Bill Williams was used to help design the Minute 319 environmental flow in the delta of the Colorado River in 2014. Water was released as a short, one-time pulse during spring with the intent of starting new cohorts of cottonwood and willow. However, fluvial disturbance was limited by the relatively small magnitude pulse, low flows did not continue throughout the growing season in some reaches, native tree recruitment was low, and most of the new plants recruited were Tamarix . The inundated portion of the floodplain did respond with a temporary increase in greenness as measured by satellite vegetation indices, however. The Murrumbidgee River in Australia is a tributary in the Murray-Darling River Basin, which supports iconic red gum ( Eucalyptus camaldulensis ) forests that depend on near-yearly floods for maintenance. During the recent Millennial Drought (2000–2010) environmental flows were provided on an experimental basis to small portions of the Yanga National Forest to see how much water was needed. As with the Colorado River delta, gains in vegetation vigor as measured by satellite vegetation indices following the flows were temporary. Environmental flows in the Bill Williams were able to restore enough overbank flooding and fluvial disturbance to promote some establishment of new cohorts of trees, but on the Colorado and Murrumbidgee Rivers larger volumes of total flows released over longer periods and targeted restoration will be needed to restore the ecosystems. A measure of success in restoring the Euphrates poplar forest on the Tarim and germinating new chorts of willows on the Bill Williams has been achieved after 15–20 years of environmental flows, but the Colorado River delta and Murrumbidgee Rivers have only received one or two flows. Success in enhancing native trees in the Colorado delta has been achieved in restoration plots, but the Murrumbidgee will require large overbank flows on a continuing schedule to rejuvenate the red gum forest.

Ecological Engineering↗
USGS1998

N2O emissions from a nitrogen-enriched river

Nitrous oxide (N2O) emissions from the South Platte River in Colorado were measured using closed chambers in the fall, winter, and summer of 1994- 1995. The South Platte River was enriched in inorganic N (9-800 ??M) derived from municipal wastewater effluent and groundwater return flows from irrigated agricultural fields. River water was as much as 2500% supersaturated with N2O, and median N2O emission rates from the river surface ranged from less than 90 to 32 600 ??g-N m-2 d-1. Seventy-nine percent of the variance in N2O emission rates was explained by concentrations of total inorganic N in river water and by water temperature. The estimated total annual N2O emissions from the South Platte River were 2 x 1013-6 x 1013 ??g-N yr-1. This amount of annual N2O emissions was similar to the estimated annual N2O emissions from all primary municipal wastewater treatment processes in the United States (1). Results from this study indicate that N-enriched rivers could be important anthropogenic sources of N2O to the atmosphere. However, N2O emission measurements from other N-enriched rivers are needed to better quantify this source.Nitrous oxide (N2O) emissions from the South Platte River in Colorado were measured using closed chambers in the fall, winter, and summer of 1994-1995. The South Platte River was enriched in inorganic N (9-800 ??M) derived from municipal wastewater effluent and groundwater return flows from irrigated agricultural fields. River water was as much as 2500% supersaturated with N2O, and median N2O emission rates from the river surface ranged from less than 90 to 32 600 ??g-N m-2 d-1. Seventy-nine percent of the variance in N2O emission rates was explained by concentrations of total inorganic N in river water and by water temperature. The estimated total annual N2O emissions from the South Platte River were 2??1013-6??1013 ??g-N yr-1. This amount of annual N2O emissions was similar to the estimated annual N2O emissions from all primary municipal wastewater treatment processes in the United States. Results from this study indicate that N-enriched rivers could be important anthropogenic sources of N2O to the atmosphere. However, N2O emission measurements from other N-enriched rivers are needed to better quantify this source.

Environmental Science & Technology↗
USGS1947

Preliminary report on stratigraphy and structure of the area of Kigalik and Awuna Rivers, Alaska

During the summer of. 1947, U. S. Geological Survey Party No. 2 made a reconnaissance survey of the area between Awuna River and the divide north of the Kigalik River. The westernmost observations were made along the Awuna anticline to longitude about 157°30' W. and along the Kigalik anticline to longitude about 156°55'W. The easternmost work was done along the Knife Blade Ridge anticline at a longitude of about 154°30'W. Not all of this area was traversed, but a general idea of the area studied may be had by noting the distribution of dip and strike symbols on Figure 1. Parts of this area had been previously visited by Smith 1/ in 1927 as a part of his traverse from Allakaket to the Arctic Coast. In the period from about July 10 to August 5 his party ascended the Awuna River and Birthday Creek, portaged over the Kigalik-Awuna divide at Birthday Pass, and descended the Kigalik River to its mouth. Various parties in the field season of 1946 worked in areas not far distant. Webber 2/ began his field work near the headwaters of the Meade River and measured a section across the Kigalik anticline about 25 miles beyond the westernmost observations made on that structure by Party No. 2. Work by Chapman and Thurrell 3/ along the Colville River parallels at a distance of three or four miles work by Party No. 2 in the vicinity of Knife Blade Ridge. The easternmost observations by Party No. 2 in the vicinity of Knife Blade Ridge are about 11 miles west of the area south of Maybe Creek mapped by Ray and Fischer.4/ Of the 1947 work of other field parties that of Thurrell 5/ along the Colville River is most closely related to this report. His thickness from the base of Zone A to his Trace No. 5 is included in Column 1 of Figure 3. Webber's work 6/ along the Ikpikpuk and Titaluk Rivers is also in a closely related area. Party No. 2 moved through this area by weasel, the weasels being used extensively on the daily traverses. The party assembled at Umiat late in May and was flown out to a lake about one mile west of the Ikpikpuk River at latitude 69°40' N. where the weasels and initial supplies had been previously cached. Early in June the party moved south into the area in which it was to begin work. For the next several weeks the party worked in the area north of the Kigalik River, moving westward along the divide north of that river. At this time considerable work was done south of the Kigalik River, west of longitude 154°40'W. No closure was detected along the Kigalik anticline. Shortly after the middle of July the party moved southwestward to the vicinity of the Awuna anticline where a westerly plunge had been suggested from the study of aerial photographs. The general route of the party from then on was eastward along the divide between the Awuna and Kigalik Rivers. Due to the need to reach a food cache further east very little data was gathered in the area between Birthday and Section Creeks. It was intended to work this area by one or two spike trips from the camp at the head of Section Creek. However, after constructing a cross-section from data gathered by the party along Section Creek and by Thurreli in the area between the Colville and Awuna Rivers it became apparent that the strata exposed along the axis of the Awuna anticline were stratigraphically below the base of Zone A. It thus appeared that there would be little point in attempting to gather additional data in the area between Birthday and Section Creeks. The party continued eastward, working along the south flank of the Kigalik anticline. On September 1, the party camped about one mile west of the summit of Knife Blade Ridge. Because of unfavorable weather at this time only a small amount of field work was accomplished in the next week. Enough data was gathered to give a general picture of the structure here, but the data on stratigraphy and structure is far from exhaustive. On September 9 the party moved eastward, camping that night about 3 miles northeast of :Wolf Creek, and arriving at Umiat on the afternoon of September 10. Aerial photographs were carried in the field and used to record the points at which observations were made. A considerable amount of data was recorded on the photographs. Approximate elevations were obtained, at first by aneroid barometers, and later by more sensitive airplane altimeters. Plane table and alidade were used in local traverses in the area north of the Kigalik River to obtain dips and strikes by the 'three-point method. Nearly all other dips and strikes recorded were measured by Brunton compass. Dips of 5° or less in the area south of the Kigalik River should, in general, be considered as dip components with only the approximate strike shown. These low dips were taken on bedding traces* where it was usually impossible to observe an accurate strike with the Brunton.

Alaska↗
USGS2021

Evaluation of factors affecting migration success of adult sockeye salmon (Oncorhynchus nerka) in the Yakima River, Washington, 2020

A study was conducted during June–October 2020 to evaluate factors affecting the migration success of adult sockeye salmon ( Oncorhynchus nerka ) in the Yakima River, Washington. A total of 144 adult sockeye salmon were tagged and released during the study. Most fish (112 fish) were collected, tagged with passive integrated transponder (PIT), and released at the mouth of the Yakima River. The remaining fish were tagged with a radio transmitter and PIT tag: 13 fish were collected, tagged, and released at Prosser Dam; 13 fish were collected and tagged at Prosser Dam, transported downstream, and released at the mouth of the Yakima River; and 6 fish were collected, tagged, and released at the mouth of the Yakima River. Radio-tagged fish released at Prosser Dam initially moved upstream and spread out in the river reach between Prosser and Sunnyside Dams, but all fish stopped moving and several transmitters were recovered. Detection records and temperature data from recovered transmitters were the basis for inferring that avian predators consumed at least 6 of the 13 fish. Fifteen of the 19 radio-tagged sockeye salmon released at the mouth of the Yakima River moved upstream in the Columbia River and were detected at Johnson Island in the Hanford Reach, or at Priest Rapids Dam. Two of these fish, tagged on August 7, eventually moved back downstream and entered the Yakima River when water temperatures in the lower Yakima River were 16–18 degrees Celsius (°C). One fish moved upstream to Sunnyside Dam where its tag was later recovered. The other fish moved farther upstream and was detected at Prosser Dam, but eventually moved downstream and its tag was recovered near Benton City, Washington. None of the recovered tags were found near a carcass. More than one-half of the sockeye salmon that were collected, tagged, and released at the mouth of the Yakima River were subsequently detected, and the greatest proportion of fish from groups released during June, July, and August entered the Yakima River. This finding suggests that adult sockeye salmon are present at the mouth of the Yakima River throughout the summer. Detection records for tagged fish at monitoring sites located near cool water inputs in the lower Yakima River suggest that sockeye salmon do not spend a substantial amount of time at these locations. Fish count data at Prosser Dam fish ladders showed that sockeye salmon had a bi-modal pattern of upstream migration with peaks in late June/early July and September when water temperature in the lower Yakima River was 20 °C or less. Sixty-one percent of PIT-tagged sockeye salmon detected at Prosser Dam were eventually collected at the adult fish trapping facility at Roza Dam where fish are collected and transported upstream to Cle Elum Reservoir. These data, in conjunction with results from other studies, suggest that a substantial proportion of Yakima River sockeye salmon fail to arrive at Roza Dam. Additional research will be required to better understand factors affecting Yakima River sockeye salmon.

Washington↗
USGS2013

Occurrence and transport of nutrients in the Missouri River Basin, April through September 2011

Heavy snow and early spring rainfall generated substantial amounts of runoff and flooding in the upper part of the Missouri River Basin in 2011. Spring runoff in the upper and middle parts of the basin exceeded the storage capacity of the Missouri River reservoirs and unprecedented amounts of water were released into the lower parts of the basin resulting in record floods from June through September on the Missouri River in Iowa and Nebraska and extending into Kansas and Missouri. Runoff from the Missouri River Basin in April through September 2011 was 8,440,000 hectare meters (68,400,000 acre feet) and was only exceeded during flooding in 1993 when runoff was 11,200,000 hectare meters (90,700,000 acre feet). Nitrate and total phosphorus concentrations in the Missouri River and selected tributaries in April through September, 2011 generally were within the expected range of concentrations measured during the last 30 years. Substantial discharge from the upper and middle parts of the Missouri River Basin resulted in nitrate concentrations decreasing in the lower Missouri River beginning in June. Concentrations of nitrate in water entering the Mississippi River from the Missouri River were less in 2011 than in 1993, but total phosphorus concentrations entering the Mississippi River were substantially greater in 2011 than in 1993. The Missouri River transported an estimated 79,600 megagrams of nitrate and 38,000 megagrams of total phosphorus to the Mississippi River from April through September 2011. The nitrate flux in 2011 was less than 20 percent of the combined total from the Upper Mississippi and Missouri River Basins. In contrast, the total phosphorus flux of 38,000 megagrams from the Missouri River constituted about 39 percent of the combined total from the Upper Mississippi and Missouri River Basins during April through September 2011. Substantially more nitrate but less total phosphorus was transported from the Missouri River Basin during the historic 1993 than during the 2011 flood. Greater runoff from the lower part of the basin contributed to the greater nitrate transport in 1993. In addition to the differing amounts of runoff and the source of flood waters, changes in land use, and management practices are additional factors that may have contributed to the difference in nitrate and total phosphorus flux between the 1993 and 2011 floods.

Iowa, Kansas, Missouri, Nebraska↗
USGS2004

Fish communities of the Buffalo River Basin and nearby basins of Arkansas and their relation to selected environmental factors, 2001-2002

The Buffalo River lies in north-central Arkansas and is a tributary of the White River. Most of the length of the Buffalo River lies within the boundaries of Buffalo National River, a unit of the National Park Service; the upper 24 river kilometers lie within the boundary of the Ozark National Forest. Much of the upper and extreme lower parts of the basin on the south side of the Buffalo River is within the Ozark National Forest. During the summers of 2001 and 2002, fish communities were sampled at 52 sites in the study area that included the Buffalo River Basin and selected smaller nearby basins within the White River Basin in north-central Arkansas. Water quality (including nutrient and bacteria concentrations) and several other environmental factors (such as stream size, land use, substrate size, and riparian shading) also were measured. A total of 56 species of fish were collected from sites within the Buffalo River Basin in 2001 and 2002. All 56 species also were collected from within the boundaries of Buffalo National River. Twenty-two species were collected from headwater sites on tributaries of the Buffalo River; 27 species were collected from sites within or immediately adjacent to the Ozark National Forest. The list of species collected from Buffalo National River is similar to the list of species reported by previous investigators. Species richness at sites on the mainstem of the Buffalo River generally increased in a downstream direction. The number of species collected (both years combined) increased from 17 at the most upstream site to 38 near the mouth of the Buffalo River. In 2001 and 2002, a total of 53 species of fish were collected from sites outside the Buffalo River Basin. Several fish community metrics varied among sites in different site categories (mainstem, large tributary, small tributary, headwater, and developed out-of-basin sites). Median relative abundances of stonerollers ranged from about 25 to 55 percent and were highest at headwater and developed out-of-basin sites and lowest at mainstem sites. The relative abundances at the headwater and developed out-of-basin sites were significantly different from the relative abundances at the mainstem sites. Percentages of individuals of algivorous/herbivorous, invertivorous, and piscivorous species at headwater sites were significantly lower than values at mainstem and developed out-of-basin sites. Percentages of individuals of invertivorous species at mainstem sites were significantly higher than values at small tributary, headwater, and developed out-of-basin sites. Percentages of top carnivores at mainstem sites were significantly higher than values at tributary and headwater sites. The numbers of darter, sculpin, plus madtom species at mainstem, large tributary, and developed out-of-basin sites were significantly higher than values at other sites, and the values at small tributary sites and headwater sites were each significantly different from values at the other four types of sites. The number of lithophilic spawning species at large tributary sites was not significantly different from values at mainstem and developed out-of-basin sites, but values for small tributary and headwater sites each were significantly different from values for all other categories. Index of biotic integrity scores varied among the site categories. Scores for mainstem sites were significantly larger than all but large tributary site scores. Scores for headwater sites were significantly smaller than mainstem and large tributary site scores. Several analyses of the data described in this report suggest that drainage area is the most important single factor influencing fish communities of the Buffalo River Basin and nearby basins. Species richness increases with increasing drainage area and some species are restricted to smaller streams while other species are more common in larger streams. Some community metrics also are related to land use and related factors

Scientific Investigations Report↗
USGS2004

Streamflow and water-quality characteristics at selected sites of the St. Johns River in central Florida, 1933 to 2002

To meet water-supply needs in central Florida for 2020, the St. Johns River is being considered as a source of water supply to augment ground water from the Floridan aquifer system. Current (2004) information on streamflow and water-quality characteristics of the St. Johns River in east-central Florida is needed by water resources planners to assess the feasibility of using the river as an alternate source of water supply and to design water treatment facilities. To address this need, streamflow and water quality of the 90-mile-long middle reach of the St. Johns River, Florida, from downstream of Lake Poinsett to near DeLand, were characterized by using retrospective (1991-99) and recently collected data (2000-02). Streamflow characteristics were determined by using data from water years 1933-2000. Water-quality characteristics were described using data from 1991-99 at 15 sites on the St. Johns River and 1 site each near the mouths of the Econlockhatchee and Wekiva Rivers. Data were augmented with biweekly water-quality data and continuous physical properties data at four St. Johns River sites and quarterly data from sites on the Wekiva River, Blackwater Creek, and downstream of Blue Springs from 2000-02. Water-quality constituents described were limited to information on physical properties, major ions and other inorganic constituents, nutrients, organic carbon, suspended solids, and phytoplankton chlorophyll-a. The occurrence of antibiotics, human prescription and nonprescription drugs, pesticides, and a suite of organic constituents, which may indicate domestic or industrial waste, were described at two St. Johns River sites using limited data collected in water years 2002-03. The occurrence of these same constituents in water from a pilot water treatment facility on Lake Monroe also was described using data from one sampling event conducted in March 2003. Dissolved oxygen concentration and water pH values in the St. Johns River were significantly lower during high-flow conditions than during low-flow conditions. Low dissolved oxygen concentrations may have resulted from the input of water from marsh areas or the subsequent decomposition of organic matter transported to the river during high-flow events. Low water pH values during high-flow conditions likely resulted from the increased dissolved organic carbon concentrations in the river. Concentrations of total dissolved solids and other inorganic constituents in the St. Johns River were inversely related with streamflow. Most major ion concentrations, total dissolved solids concentrations, and specific conductance values varied substantially at the Christmas, Sanford, and DeLand sites during low-flow periods in 2000-01 probably reflecting wind and tidal effects. Sulfide concentrations as high as 6 milligrams per liter (mg/L) were measured in the St. Johns River during high-flow periods. Increased sulfide concentrations likely resulted from the decomposition of organic matter or the reduction of sulfate. Bromide concentrations as high as 17 mg/L were measured at the most upstream site on the St. Johns River during 2000-02. Temporal variations in bromide were characterized by sharp peaks in concentration during low-flow periods. Peaks in bromide concentrations tended to coincide with peaks in chloride concentrations because the likely source of both constituents is ground water affected by relict seawater. Median dissolved organic carbon concentrations ranged from 15 to 26 mg/L during 2000-02, and concentrations as high as 42 mg/L were measured. Water color values and dissolved organic carbon concentrations generally were significantly greater during high-flow conditions than during low-flow conditions. Specific ultraviolet light absorbance data indicated the organic carbon during high-flow events was more aromatic in composition and likely originated from terrestrially derived sources compared to organic carbon in the river during other times of the year. D

Scientific Investigations Report↗
USGS2007

Simulation of the effects of water withdrawals, wastewater-return flows, and land-use change on streamflow in the Blackstone River basin, Massachusetts and Rhode Island

Streamflow in many parts of the Blackstone River Basin in south-central Massachusetts and northern Rhode Island is altered by water-supply withdrawals, wastewater-return flows, and land-use change associated with a growing population. Simulations from a previously developed and calibrated Hydrological Simulation Program—FORTRAN (HSPF) precipitation-runoff model for the basin were used to evaluate the effects of water withdrawals, wastewater-return flows, and land-use change on streamflow. Most of the simulations were done for recent (1996–2001) conditions and potential buildout conditions in the future when all available land is developed to provide a long-range assessment of the effects of possible future human activities on water resources in the basin. The effects of land-use change were evaluated by comparing the results of long-term (1960–2004) simulations with (1) undeveloped land use, (2) 1995–1999 land use, and (3) potential buildout land use at selected sites across the basin. Flow-duration curves for these land-use scenarios were similar, indicating that land-use change, as represented in the HSPF model, had little effect on flow in the major tributary streams and rivers in the basin. However, land-use change—particularly increased effective impervious area—could potentially have greater effects on the hydrology, water quality, and aquatic habitat of the smaller streams in the basin. The effects of water withdrawals and wastewater-return flows were evaluated by comparing the results of long-term simulations with (1) no withdrawals and return flows, (2) actual (measured) 1996–2001 withdrawals and wastewater-return flows, and (3) potential withdrawals and wastewater-return flows at buildout. Overall, the results indicated that water use had a much larger effect on streamflow than did land use, and that the location and magnitude of wastewater-return flows were important for lessening the effects of withdrawals on streamflow in the Blackstone River Basin. Ratios of long-term (1960–2004) simulated flows with 1996–2001 water use (representing the net effect of withdrawals and wastewater-return flows) to long-term simulated flows with no water use indicated that, for many reaches, 1996–2001 water use did not deplete flows at the 90-percent flow duration substantially compared to flows unaffected by water use. Flows generally were more severely depleted in the reaches that include surface-water supplies for the larger cities in the basin (Kettle and Tatnuck Brooks, Worcester, Mass. water supply; Quinsigamond River, Shrewsbury, Mass. water supply; Crookfall Brook, Woonsocket, R.I. water supply; and Abbott Run, Pawtucket, R.I. water supply). These reaches did not have substantial wastewater-return flows that could offset the effects of the withdrawals. In contrast, wastewater-return flows from the Upper Blackstone Wastewater Treatment Facility in Millbury, Mass. increased flows at the 90-percent flow duration in the main stem of the Blackstone River compared to no-water-use conditions. Under the assumptions used to develop the buildout scenario, nearly all of the new water withdrawals were returned to the Blackstone River Basin at municipal wastewater-treatment plants or on-site septic systems. Consequently, buildout generally had small effects on simulated low flows in the Blackstone River and most of the major tributary streams compared to flows with 1996–2001 water use. To evaluate the effects of water use on flows in the rivers and major tributary streams in the Rhode Island part of the basin in greater detail, the magnitudes of water withdrawals and wastewater-return flows in relation to simulated streamflow were calculated as unique ratios for individual HSPF subbasins, total contributing areas to HSPF subbasins, and total contributing areas to the major tributary streams. For recent conditions (1996–2001 withdrawals and 1995–1999 land use), ratios of average summer (June through September) withdrawals to the long-term (1960–2004) medians of average summer streamflow simulated in the absence of water use ranged from 0.039 to 2.5 with a median value of 0.11 for total contributing areas to HSPF subbasins. The largest ratios of withdrawal rates to streamflow were for Crookfall Brook and Abbott Run, the subbasins with major withdrawals for municipal water supply. The smallest ratios were for the rural subbasins in the Branch River drainage area in the southwestern part of the basin. For recent conditions, ratios of average summer wastewater-return flows to average summer streamflows ranged from 0.0 to 0.20 with a median value of 0.029 for total contributing areas to HSPF subbasins. The largest ratios of wastewater-return flows to streamflows were for the subbasins that contained return flows from municipal wastewater-treatment plants and the subbasins along the Blackstone River because of high wastewater-return-flow rates from upstream facilities. Under the assumptions used to develop the buildout analysis, withdrawal and return-flow ratios were estimated to increase for most of the HSPF subbasins in the Rhode Island part of the basin. Ratios more than doubled for some subbasins, but the large increases mainly were for subbasins that had low ratios in 1996–2001. The HSPF model also was used to estimate the effects of water-conservation measures on low flows in rivers and major tributary streams in the Rhode Island part of the basin, the contribution of wastewater-return flows to streamflow in the Blackstone River, and the effects of changes to two local water supplies in Rhode Island. Water-conservation measures were evaluated by reducing 1996–2001 withdrawals by 20 percent. Simulations with 20-percent reductions in withdrawal rates indicated that conservation measures would result in appreciable increases in low flows in the subbasins with the highest withdrawal rates in the Rhode Island part of the Blackstone River Basin, whereas the effects on streamflow would be much less pronounced in subbasins with lower withdrawal rates. The contribution of wastewater-return flows to streamflow in the Blackstone River was evaluated by comparing simulated flows with and without municipal wastewater-return flows. Under typical summer low-flow conditions, treated wastewater was a major component of streamflow (35 to 50 percent) in the Blackstone River, and the percentage of treated wastewater was larger during the driest periods. The simulations conducted to evaluate changes to local water supplies (effects of potential withdrawals from an inactive well adjacent to Slatersville Reservoir in North Smithfield on flows in the Branch River, and the effects of connecting the town of North Smithfield to the water-supply system for the city of Woonsocket, Rhode Island) indicated that each of these activities would alter low flows only slightly in the associated stream reaches.

Massachusetts, Rhode Island↗
USGS2007

Temperature Effects of Point Sources, Riparian Shading, and Dam Operations on the Willamette River, Oregon

Water temperature is an important factor influencing the migration, rearing, and spawning of several important fish species in rivers of the Pacific Northwest. To protect these fish populations and to fulfill its responsibilities under the Federal Clean Water Act, the Oregon Department of Environmental Quality set a water temperature Total Maximum Daily Load (TMDL) in 2006 for the Willamette River and the lower reaches of its largest tributaries in northwestern Oregon. As a result, the thermal discharges of the largest point sources of heat to the Willamette River now are limited at certain times of the year, riparian vegetation has been targeted for restoration, and upstream dams are recognized as important influences on downstream temperatures. Many of the prescribed point-source heat-load allocations are sufficiently restrictive that management agencies may need to expend considerable resources to meet those allocations. Trading heat allocations among point-source dischargers may be a more economical and efficient means of meeting the cumulative point-source temperature limits set by the TMDL. The cumulative nature of these limits, however, precludes simple one-to-one trades of heat from one point source to another; a more detailed spatial analysis is needed. In this investigation, the flow and temperature models that formed the basis of the Willamette temperature TMDL were used to determine a spatially indexed 'heating signature' for each of the modeled point sources, and those signatures then were combined into a user-friendly, spreadsheet-based screening tool. The Willamette River Point-Source Heat-Trading Tool allows the user to increase or decrease the heating signature of each source and thereby evaluate the effects of a wide range of potential point-source heat trades. The predictions of the Trading Tool were verified by running the Willamette flow and temperature models under four different trading scenarios, and the predictions typically were accurate to within about 0.005 degrees Celsius (?C). In addition to assessing the effects of point-source heat trades, the models were used to evaluate the temperature effects of several shade-restoration scenarios. Restoration of riparian shade along the entire Long Tom River, from its mouth to Fern Ridge Dam, was calculated to have a small but significant effect on daily maximum temperatures in the main-stem Willamette River, on the order of 0.03?C where the Long Tom River enters the Willamette River, and diminishing downstream. Model scenarios also were run to assess the effects of restoring selected 5-mile reaches of riparian vegetation along the main-stem Willamette River from river mile (RM) 176.80, just upstream of the point where the McKenzie River joins the Willamette River, to RM 116.87 near Albany, which is one location where cumulative point-source heating effects are at a maximum. Restoration of riparian vegetation along the main-stem Willamette River was shown by model runs to have a significant local effect on daily maximum river temperatures (0.046 to 0.194?C) at the site of restoration. The magnitude of the cooling depends on many factors including river width, flow, time of year, and the difference in vegetation characteristics between current and restored conditions. Downstream of the restored reach, the cooling effects are complex and have a nodal nature: at one-half day of travel time downstream, shade restoration has little effect on daily maximum temperature because water passes the restoration site at night; at 1 full day of travel time downstream, cooling effects increase to a second, diminished maximum. Such spatial complexities may complicate the trading of heat allocations between point and nonpoint sources. Upstream dams have an important effect on water temperature in the Willamette River system as a result of augmented flows as well as modified temperature releases over the course of the summer and autumn. The TMDL was formulated prior t

Scientific Investigations Report↗
USGS2008

Determination of Organic and Inorganic Percentages and Mass of Suspended Material at Four Sites in the Illinois River in Northwestern Arkansas and Northeastern Oklahoma, 2005-07

The Illinois River located in northwestern Arkansas and northeastern Oklahoma is influenced by point and nonpoint sources of nutrient enrichment. This has led to increased algal growth within the stream, reducing water clarity. Also, sediment runoff from fields, pastures, construction sites, and other disturbed areas, in addition to frequent streambank failure, has increased sedimentation within the stream and decreased water clarity. A study was conducted by the U.S. Geological Survey in cooperation with the Arkansas Department of Environmental Quality and the U.S. Environmental Protection Agency to characterize the increased turbidity by determining the organic and inorganic composition and mass of suspended material in the Illinois River from August 2005 through July 2007. Water-quality samples were collected at four sites on the Illinois River (listed in downstream order): near Viney Grove, Arkansas; at Savoy, Arkansas; south of Siloam Springs, Arkansas; and near Tahlequah, Oklahoma. In general, turbidity, total suspended solids, suspended-sediment concentration, organic material concentration (measured as volatile suspended solids and ash-free dry mass), and chlorophyll a concentration were the greatest in samples collected from the Illinois River at Savoy and the least in samples from the most upstream Illinois River site (near Viney Grove) and the most downstream site (near Tahlequah) from August 2005 through July 2007. For example, the suspended-sediment concentration at the Illinois River at Savoy had a median of 15 milligrams per liter, and the total suspended solids had a median of 12 milligrams per liter. The Illinois River near Tahlequah had the least suspended-sediment concentration with a median of 10 milligrams per liter and the least total suspended solids with a median of 6 milligrams per liter. The turbidity, total suspended solids, suspended-sediment concentration, organic material concentration, and chlorophyll a concentration in samples collected during high-flow events were greater than in samples collected during base-flow conditions at the Illinois River at Savoy, south of Siloam Springs, and near Tahlequah. For example, the median turbidity for the Illinois River at Savoy was 3 nephelometric turbidity ratio units during base-flow conditions and 52 nephelometric turbidity ratio units during high-flow conditions. Organic material in the Illinois River generally composed between 13 and 47 percent of the total suspended material in samples collected from August 2005 through July 2007. Therefore, most of the suspended material in samples collected from the sites was inorganic material. Overall, the highest percentage of organic material was found at the Illinois River near Viney Grove and at the Illinois River near Tahlequah. The Illinois River south of Siloam Springs had the lowest percentage of organic material among the four sites. In general, the percentage of organic material was greater in samples collected during base-flow conditions compared to samples collected during high-flow conditions. The mean seasonal concentrations and percentages of organic material were the least in the fall (September through November) in samples collected from August 2005 to July 2007 from the four Illinois River sites, while the greatest concentrations and percentages of organic material occurred at various times of the year depending on the site. The greatest concentrations of organic material occurred in the summer (June through August) in samples from sites on the Illinois River near Viney Grove, at Savoy and south of Siloam Springs, but in the spring (March through May) in samples from the Illinois River near Tahlequah. The greatest percentages of organic material (least percentages of inorganic material) occurred in the summer in samples from the site near Viney Grove, the winter and summer at the site at Savoy, in the spring, fall, and winter (December through February) at the site south of Siloam Springs, an

Scientific Investigations Report↗
USGS2011

Potential water-quality effects of coal-bed methane production water discharged along the upper Tongue River, Wyoming and Montana

Water quality in the upper Tongue River from Monarch, Wyoming, downstream to just upstream from the Tongue River Reservoir in Montana potentially could be affected by discharge of coal-bed methane (CBM) production water (hereinafter referred to as CBM discharge). CBM discharge typically contains high concentrations of sodium and other ions that could increase dissolved-solids (salt) concentrations, specific conductance (SC), and sodium-adsorption ratio (SAR) in the river. Increased inputs of sodium and other ions have the potential to alter the river's suitability for agricultural irrigation and aquatic ecosystems. Data from two large tributaries, Goose Creek and Prairie Dog Creek, indicate that these tributaries were large contributors to the increase in SC and SAR in the Tongue River. However, water-quality data were not available for most of the smaller inflows, such as small tributaries, irrigation-return flows, and CBM discharges. Thus, effects of these inflows on the water quality of the Tongue River were not well documented. Effects of these small inflows might be subtle and difficult to determine without more extensive data collection to describe spatial patterns. Therefore, synoptic water-quality sampling trips were conducted in September 2005 and April 2006 to provide a spatially detailed profile of the downstream changes in water quality in this reach of the Tongue River. The purpose of this report is to describe these downstream changes in water quality and to estimate the potential water-quality effects of CBM discharge in the upper Tongue River. Specific conductance of the Tongue River through the study reach increased from 420 to 625 microsiemens per centimeter (.μS/cm; or 49 percent) in the downstream direction in September 2005 and from 373 to 543 .μS/cm (46 percent) in April 2006. Large increases (12 to 24 percent) were measured immediately downstream from Goose Creek and Prairie Dog Creek during both sampling trips. Increases attributed to direct CBM discharges were smaller. In September 2005, the SC of 12 measured CBM discharges ranged from 1,750 to 2,440 .μS/cm, and the combined discharges increased SC in the river by an estimated 4.5 percent. In April 2006, the SC of eight measured CBM discharges ranged from 1,720 to 2,070 μS/cm; the largest of these discharges likely increased SC in the river by 5.8 percent. Estimates of potential effects of the CBM discharges on the SC of the Tongue River near the Tongue River Reservoir were calculated using a two-step process involving linear regression and mass-balance calculations for a range of streamflow and CBM-discharge conditions. Potential effects from CBM discharges are larger increases of SC and SAR at lower flows than at higher flows and relative increases that are substantially smaller for SC than for SAR. For example, if the streamflow was 100 cubic feet per second (ft 3 /s) in the Tongue River near the Tongue River Reservoir and CBM discharge ranged from 1,250 to 5,000 gallons per minute, the projected increases would range from 4.4 to 16 percent for SC and from 39 to 151 percent for SAR. In comparison, if the streamflow was 600 ft 3 /s, the projected increases would range from 2.2 to 8.4 percent for SC and from 21 to 79 percent for SAR. This analysis of potential water-quality effects on the SC and SAR of the Tongue River in the study area assumes that the quantity and quality of water flowing into the study reach at the time of this study was the same as during the period before CBM development (data from water years 1985-99).

Wyoming;Montana↗
USGS2012

Sediment loads in the Red River of the North and selected tributaries near Fargo, North Dakota, 2010--2011

Natural-resource agencies are concerned about possible geomorphic effects of a proposed diversion project to reduce the flood risk in the Fargo-Moorhead metropolitan area. The U.S. Geological Survey in cooperation with the U.S. Army Corps of Engineers collected data in the spring of 2010 and 2011, and from June to November 2011, during rainfall-runoff events and base-flow conditions to provide information on sediment transport. The data were used to examine sediment concentrations, loads, and particle-size distributions at nine selected sites in the Red River and its tributaries near the Fargo-Moorhead metropolitan area. Suspended-sediment concentration varied among sites in 2010 and 2011. The least suspended-sediment concentrations were measured at the Red River (site 1) and the Buffalo River (site 9), and the greatest concentrations were measured at the two Sheyenne River sites (sites 3 and 4). Estimated daily suspended-sediment loads were highly variable in 2010 and 2011 in the Red River and its tributaries, with the greatest loads occurring in the spring and the smallest loads occurring in the winter. For the Red River, daily suspended-sediment loads ranged from 26 to 3,500 tons per day at site 1 and from 30 to 9,010 tons per day at site 2. For the Sheyenne River, daily loads ranged from less than 10 to 10,200 tons per day at site 3 and from less than 10 to 4,530 tons per day at site 4. The mean daily load was 191 tons per day in 2010 and 377 tons per day in 2011 for the Maple River, and 610 tons per day in 2011 for the Wild Rice River (annual loads were not computed for 2010). For the three sites that were only sampled in 2011 (sites 7, 8 and 9), the mean daily suspended-sediment loads ranged from 40 tons per day at the Lower Branch Rush River (site 8) to 118 tons per day at the Buffalo River (site 9). For sites that had estimated loads in 2010 and 2011 (sites 1–5), estimated annual (March–November) suspended-sediment loads were greater in 2011 compared to 2010. In 2010, annual loads ranged from 68,650 tons per year at the Maple River (site 5) to 249,040 tons per year at the Sheyenne River (site 3). In 2011, when all nine sites were sampled, annual loads ranged from 8,716 tons per year at the Lower Branch Rush River (site 8) to 552,832 tons per year at the Sheyenne River (site 3). With the exception of the Sheyenne River (site 4), the greatest monthly loads occurred in March for 2010, with as little as 27 percent (site 1) and as much as 42 percent (site 3) of the annual load occurring in March. For 2011, the greatest monthly loads occurred in April, ranging from 33 percent (site 1) to 63 percent (site 7) of the 2011 annual load. A relatively small amount of sediment was transported past the nine sites as bedload in 2010 and 2011. For most of the samples collected at the nine sites, the bedload composed less than 1 percent of the calculated daily total sediment load.

North Dakota↗
USGS2021

Simulation of groundwater flow in the aquifer system of the Anacostia River and surrounding watersheds, Washington, D.C., Maryland, and Virginia

The U.S. Geological Survey, in cooperation with the District Department of Energy & Environment, Water Quality Division, is investigating the hydrogeology of the tidal Anacostia River watershed within Washington, D.C., with the goal of improving understanding of the groundwater-flow system and the interaction of groundwater and surface water in the watershed. To help meet this goal, a three-dimensional steady-state groundwater-flow model for the Anacostia River and surrounding watersheds in Washington, D.C., Maryland, and Virginia was constructed. The goal of the modeling study was to quantify the rate and pattern of groundwater flow to the tidal Anacostia River. The model domain includes weathered and unweathered rocks of the Piedmont Physiographic Province and the southeast-dipping sediments of the Atlantic Coastal Plain Physiographic Province. The model includes processes of recharge, evapotranspiration, withdrawals from wells, and base flow to streams, rivers, and tidal waters. Final model calibration was achieved by using the objective parameter estimation and sensitivity analysis capabilities of UCODE_2005. Simulated gradients in the surficial aquifer in the vicinity of the tidal Anacostia River indicate that flow is predominantly toward the river, with changes in the magnitude and direction of the gradients from the northeast, where the Anacostia River enters Washington, D.C., to the southwest, toward the confluence with the tidal Potomac River. Flow paths to the tidal Anacostia River from the north are largely horizontal through the surficial aquifer and Patuxent aquifer. From the south, the flow paths toward the river originate in the elevated topographic areas southeast of the river and pass through the surficial aquifer and Patapsco confining unit, lower Patapsco aquifer/Arundel Clay, and to some extent, the Patuxent aquifer. Groundwater-flow rates to and from the tidal rivers (Potomac and Anacostia) are generally greatest near the land-water boundary, where the gradient in the water table is greatest, and diminish toward the middle of the tidal river channels. The tidal rivers are predominantly areas of groundwater discharge, although there are areas where tidal waters are recharging the subsurface, typically where small variations or depressions in the topography produce small locally reversed gradients in the water table. Substantial recharge of tidal waters to the groundwater system is observed for the tidal Potomac where the upper Patapsco aquifer subcrops south of Washington, D.C. Water budget calculations indicate that inflows to the groundwater system beneath the tidal Anacostia River are predominantly from the land area of Washington, D.C., followed by tidal surface water and flows from lower layers. Outflows are largely to the tidal Anacostia River, with a smaller part going to the land area underlying Washington, D.C.

Delaware, Maryland, Washington D.C.↗
USGS2014

Simulation of the Lower Walker River Basin hydrologic system, west-central Nevada, using PRMS and MODFLOW models

Walker Lake is a terminal lake in west-central Nevada with almost all outflow occurring through evaporation. Diversions from Walker River since the early 1900s have contributed to a substantial reduction in flow entering Walker Lake. As a result, the lake is receding, and salt concentrations have increased to a level in which Oncorhynchus clarkii henshawi (Lahontan Cutthroat trout) are no longer present, and the lake ecosystem is threatened. Consequently, there is a concerted effort to restore the Walker Lake ecosystem and fishery to a level that is more sustainable. However, Walker Lake is interlinked with the lower Walker River and adjacent groundwater system which makes it difficult to understand the full effect of upstream water-management actions on the overall hydrologic system including the lake level, volume, and dissolved-solids concentrations of Walker Lake. To understand the effects of water-management actions on the lower Walker River Basin hydrologic system, a watershed model and groundwater flow model have been developed by the U.S. Geological Survey in cooperation with the Bureau of Reclamation and the National Fish and Wildlife Foundation. The watershed model was developed using the precipitation runoff modeling system (PRMS) and the groundwater flow model was constructed using the MODular groundwater FLOW model (MODFLOW) and both were calibrated for the lower Walker River Basin. These models can be incorporated in an integrated Groundwater and Surface-water FLOW (GSFLOW) model of the lower Walker River Basin. Additionally, the MODFLOW model developed for this study is useful for efficiently simulating long-term and large-scale effects of water-management actions on groundwater hydrology, streamflow, and Walker Lake level, volume, and dissolved-solids concentrations. The lower Walker River Basin PRMS model (LWR_PRMS) was constructed using a subbasin approach to aid in development and calibration, and simulates a 30-year period from 1978 to 2007 using daily time steps. The LWR_PRMS was used to estimate the distribution of groundwater recharge specified in the MODFLOW model. The highest rates of groundwater recharge occur in the Wassuk Range beneath perennial and ephemeral stream channels, whereas lower rates of recharge occur beneath alluvial fans along mountain fronts. The total groundwater recharge estimated using PRMS was about 25,000 acre-feet per year. The lower Walker River Basin MODFLOW (LWR_MF) model simulates an 89-year period using monthly time steps. The LWR_MF was constructed with an initial steady-state simulation to represent dynamic equilibrium conditions from 1908 to 1918 and then a transient simulation representing the period 1919–2007. The model was calibrated using a combination of manual and automated methods of adjusting model parameters to minimize errors between model simulated results and weighted observations of groundwater levels, streamflows, and lake level. Hydrologic conditions simulated with the LWR_MF include the movement and change in storage of groundwater, and the water budgets for Walker River, Walker Lake, and the groundwater system. The LWR_MF computed dissolved-solids concentrations for Walker Lake using simulated lake volume and an assumed constant internal salt mass of 37.2 million tons. Effects of potential changes in water management on future conditions (scenarios) of the lower Walker River Basin hydrologic system and Walker Lake from 2011 to 2070 were evaluated. Several water-management scenarios were considered, including a baseline scenario that represents no changes in system management, improved irrigation efficiencies for the Walker River Indian Irrigation Project (WRIIP), a range of increased streamflows entering the lower Walker River Basin, and, the fallowing of fields on the WRIIP. For the baseline scenario, it was assumed that streamflow conditions from 1981 to 2010 will be repeated in the future. Results indicate that Walker Lake level and volume continue to decline but at a slower rate as the surface area of the lake becomes smaller and lake evaporation decreases. Dissolved-solids concentrations in Walker Lake continue to increase and increase much more rapidly during periods when minimal flows reach the lake due to a diminished lake volume. Alternatively, in years with high runoff, lake level increases are greater and dissolved-solids decreases are greater, compared with equivalent runoffs experienced during 1981–2010. The simulated effects of improving WRIIP efficiencies on Walker River streamflows, Walker Lake inflow, level, and dissolved-solids concentrations, and crop consumptive use, are compared with the baseline reference scenario for a range of irrigation efficiency improvements from 0 to 25 percent over 60 years. Results indicate that water is conserved through a reduction in irrigation-induced groundwater recharge and subsequent groundwater discharge through evapotranspiration. The conserved water mostly goes to increased streamflow to Walker Lake, followed by increased crop consumptive use, then increased evaporation from Weber Reservoir. The simulated effects of increased streamflows at Walker River at Wabuska streamgage (10301500) on Walker Lake inflow, level, and dissolved-solids concentrations, and crop consumptive use, are compared with the baseline scenario after 60 years under two different management methods for Weber Reservoir. Results indicate Walker Lake level and dissolved-solids concentrations stabilized with increased irrigation-season streamflow of about 40,000 acre-feet per year at the Walker River at Wabuska streamgage. Walker Lake level increased, and dissolved-solids concentration decreased, with increased flows of 50,000 acre-feet per year or more. After 60 years with additional irrigation-season streamflows of 50,000 acre-feet per year, Walker Lake level increased by about 48 feet, and lake dissolved-solids concentrations decreased by about 3,000 milligrams per liter (mg/L). With 75,000 acre-feet per year of additional streamflow, Walker Lake level increased by 70 feet, and dissolved-solids concentration decreased by 7,600 milligrams per liter. The effects of fallowing of Walker River Indian Irrigation Project fields from 2007 to 2010 on Walker Lake inflow, level, and dissolved solids were evaluated. Fallowing resulted in a near doubling of Walker River inflow to Walker Lake during this period, an increase in Walker Lake level of about 1.4 feet, and a decrease in dissolved-solids concentration of about 540 mg/L.

Nevada↗
USGS2015

Flooding in the South Platte River and Fountain Creek Basins in eastern Colorado, September 9–18, 2013

On September 9, 2013, rain began to fall in eastern Colorado as a large low-pressure system pulled plumes of tropical moisture northward from the Pacific Ocean and the Gulf of Mexico. By September 16, 2013, as much as 12 to 20 inches of rain had fallen in the foothills of the Front Range of the Southern Rocky Mountains and adjacent plains near Colorado Springs, Colorado, north to the Colorado-Wyoming border. The rain caused major flooding during September 9–18, 2013, in a large part of the South Platte River Basin and in the Fountain Creek Basin. The floods resulted in several fatalities, more than 31,000 damaged or destroyed structures, and an estimated 3 billion dollars in damages. The U.S. Geological Survey (USGS) documented peak stage, streamflow, or both from the flood event for 80 sites located on selected rivers and streams in the South Platte River and Fountain Creek Basins and on the Platte River in Nebraska. The majority of flood-peak streamflows occurred on September 12 or 13, 2013, coinciding with the period of maximum rainfall. The flood resulted in new record peak streamflows at 17 streamgages having at least 10 years of record; 13 in the South Platte River Basin and 4 in the Fountain Creek Basin. Flooding in the South Platte River Basin was primarily contained to select streams in Aurora and the Denver metropolitan area, most of the mountain tributaries joining the main stem South Platte River from Denver to Greeley, and in the main stem South Platte River from Denver to the Colorado-Nebraska State line. In Aurora, where about 15 inches of rain fell, streamflow peaked at 5,470 cubic feet per second (ft 3 /s) in Toll Gate Creek, a tributary to Sand Creek. Downstream from Aurora near the confluence with the South Platte River, Sand Creek peaked at 14,900 ft 3 /s, which was the highest streamflow since at least 1992, but less than the peak of 25,500 ft 3 /s in 1957 that occurred 4 miles upstream from the mouth. Flood-peak streamflows in the Denver metropolitan area were generally below historic records. The peak of 3,930 ft 3 /s on September 12 at the State of Colorado streamgage South Platte River at Denver ranked 59 out of 116 peaks and was less than the 1965 peak of 40,300 ft 3 /s. Ten of the 13 streamgages in the South Platte River Basin with new record peak streamflows were located on the mountain tributaries; Bear Creek, Fourmile Creek, Boulder Creek, St. Vrain Creek, the Big Thompson River, and the Cache la Poudre River. A daily average streamflow of 8,910 ft 3 /s on September 13 in Boulder Creek at the confluence with St. Vrain Creek was more than twice the previous instantaneous peak of 4,410 ft 3 /s from 1938. The USGS calculated a peak streamflow of 23,800 ft 3 /s for the St. Vrain Creek at Lyons; the highest streamflow on record at this State of Colorado streamgage (122 years of record) is 10,500 ft 3 /s from 1941. A peak streamflow of 16,200 ft 3 /s was calculated for the Big Thompson River at mouth of canyon near Drake streamgage, which is the second highest peak in 90 years of record and about one-half the magnitude of the peak of 31,200 ft 3 /s from July 31, 1976. A streamflow of 60,000 ft 3 /s in the South Platte River at Fort Morgan (September 15, 2013) suggests that a new record streamflow occurred in the main stem in the Greeley area, about 45 miles upstream from Fort Morgan. The current peak of record at a State of Colorado streamgage at Kersey, about 6.5 miles downstream from Greeley, is 31,500 ft 3 /s from 1973. Given that there was minimal inflow between Kersey and Fort Morgan, the USGS estimates there was probably at least 60,000 ft 3 /s at Kersey, which would be almost double the peak streamflow of record from 1973. Flooding in the Fountain Creek Basin was primarily contained to Fountain Creek from southern Colorado Springs to its confluence with the Arkansas River in Pueblo, in lower Monument Creek, and in several mountain tributaries. New record peak streamflows occurred at four mountain tributary streamgages having at least 10 years of record; Bear Creek, Cheyenne Creek, Rock Creek, and Little Fountain Creek. Five streamgages with at least 10 years of record in a 32-mile reach of Fountain Creek extending from Colorado Springs to Piñon had peak streamflows in the top five for the period of record. A peak of 15,300 ft 3 /s at Fountain Creek near Fountain was the highest streamflow recorded in the Fountain Creek Basin during the September 2013 event and ranks the third highest peak in 46 years. Near the mouth of the basin, a peak of 11,800 ft 3 /s in Pueblo was only the thirteenth highest annual peak in 74 years. A new Colorado record for daily rainfall of 11.85 inches was recorded at a USGS rain gage in the Little Fountain Creek Basin on September 12, 2013.

Colorado↗
USGS2016

Aquatic biological communities and associated habitats at selected sites in the Big Wood River Watershed, south-central Idaho, 2014

Assessments of streamflow (discharge) parameters, water quality, physical habitat, and biological communities were completed between May and September 2014 as part of a monitoring program in the Big Wood River watershed of south-central Idaho. The sampling was conducted by the U.S. Geological Survey in cooperation with Blaine County, Trout Unlimited, the Nature Conservancy, and the Wood River Land Trust to help identify the status of aquatic resources at selected locations in the watershed. Information in this report provides a basis with which to evaluate and monitor the long-term health of the Big Wood River and its major tributaries. Sampling sites were co-located with existing U.S. Geological Survey streamgaging stations: three on the main stem Big Wood River and four on the North Fork Big Wood River (North Fork), Warm Springs Creek (Warm Sp), Trail Creek (Trail Ck), and East Fork Big Wood River (East Fork) tributaries. The analytical results and quality-assurance information for water quality, physical habitat, and biological community samples collected at study sites during 2 weeks in September 2014 are summarized. Water-quality data include concentrations of major nutrients, suspended sediment, dissolved oxygen, and fecal-coliform bacteria. To assess the potential effects of nutrient enrichment on algal growth, concentrations of periphyton biomass (chlorophyll- a and ash free dry weight) in riffle habitats were determined at each site. Physical habitat parameters include stream channel morphology, habitat volume, instream structure, substrate composition, and riparian vegetative cover. Biological data include taxa richness, abundance, and stream-health indicator metrics for macroinvertebrate and fish communities. Statistical summaries of the water-quality, habitat, and biological data are provided along with discussion of how these findings relate to the health of aquatic resources in the Big Wood River watershed. Seasonal discharge patterns using statistical summaries of daily discharge from selected sites are reported for water years 2012–15. Results showed that annual average daily mean discharge increased from the Big Wood River near Ketchum, ID (BW Ketchum) downstream to the Big Wood River at Hailey, ID (BW Hailey), but decreased by nearly 50 percent from BW Hailey downstream to Big Wood River at Stanton Crossing near Bellevue, ID (BW Stanton). Annual variability in daily mean discharge among main-stem sites was highest at BW Stanton, suggesting that this part of the river may be subject to some level of flow alteration. Hydrologic alterations resulting in flow reduction can contribute to higher water temperature, especially during the summer months when conditions are often most stressful to fish and other stream organisms. Daily water temperature and water temperature trends from June to September 2014 are reported for select tributary and main-stem sites on the Big Wood River and can be used to assess the potential for biological impairment based on aquatic life temperature criteria for cold-water streams. The State of Idaho maximum temperature criteria for protection of cold-water aquatic life of 22 °C was exceeded at Warm Sp and BW Stanton during summer 2014, but at none of the other main-stem or tributary sites. The 13 °C critical temperature criterion for salmonid spawning was exceeded in early July 2014 at BW Ketchum and BW Hailey near the end of the rainbow trout critical spawning and rearing period. Temperature exceedances were most frequent at BW Stanton, where exceedances for rainbow trout and brown trout occurred from May through early July 2014 during most of the critical spawning and rearing period. Water quality and habitat availability did not seem to be limiting for fish or other aquatic organisms at most sites in the Big Wood River watershed. Water quality assessments in September 2014 determined no exceedances of total maximum daily load target levels. The availability and quality of habitat was limited at BW Stanton, where shallow-water habitat conditions prevailed. Macroinvertebrate community diversity was high at all sites except for BW Stanton, where low community diversity was attributed to low species richness and high abundances of a few tolerant taxa. Presence of low species diversity and high macroinvertebrate tolerance values at BW Stanton indicates that benthic community condition and stream health were reduced at that location. Fish surveys done in September 2014 did not indicate any significant reductions in native fish communities in the Big Wood River or its tributaries. Native rainbow trout ( Oncorhynchus mykiss ) and Wood River sculpin ( Cottus leiopomus ) were the dominant fish species in the drainage and were found at all tributary and main-stem sites. Non-native brown ( Salmo trutta ) and brook trout ( Salvelinus fontinalis ) were limited to lower drainage sites on the Big Wood River (BW Hailey and BW Stanton), and occurred in relatively low numbers.

Idaho↗
USGS2017

Suspended sediment, turbidity, and stream water temperature in the Sauk River Basin, western Washington, water years 2012-16

The Sauk River is a federally designated Wild and Scenic River that drains a relatively undisturbed landscape along the western slope of the North Cascade Mountain Range, Washington, which includes the glaciated volcano, Glacier Peak. Naturally high sediment loads characteristic of basins draining volcanoes like Glacier Peak make the Sauk River a dominant contributor of sediment to the downstream main stem river, the Skagit River. Additionally, the Sauk River serves as important spawning and rearing habitat for several salmonid species in the greater Skagit River system. Because of the importance of sediment to morphology, flow-conveyance, and ecosystem condition, there is interest in understanding the magnitude and timing of suspended sediment and turbidity from the Sauk River system and its principal tributaries, the White Chuck and Suiattle Rivers, to the Skagit River. Suspended-sediment measurements, turbidity data, and water temperature data were collected at two U.S. Geological Survey streamgages in the upper and middle reaches of the Sauk River over a 4-year period extending from October 2011 to September 2015, and at a downstream location in the lower river for a 5-year period extending from October 2011 to September 2016. Over the collective 5-year study period, mean annual suspended-sediment loads at the three streamgages on the upper, middle, and lower Sauk River streamgages were 94,200 metric tons (t), 203,000 t, and 940,000 t streamgages, respectively. Fine (smaller than 0.0625 millimeter) total suspended-sediment load averaged 49 percent at the upper Sauk River streamgage, 42 percent at the middle Sauk River streamgage, and 34 percent at the lower Sauk River streamgage.

Washington↗