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Long-term monitoring of stream-bed sediments reveals spatial and temporal trends in metal concentrations. Here we use concentration gradient “heat maps” as a visualization tool to report annual mean arsenic, cadmium and copper concentrations along a contamination gradient in the Clark Fork River (CFR) in Western Montana. The CFR has been heavily impacted by large-scale mining operations since the 19th century. Legacy mine waste and tailings have been deposited within the streambed, banks, and floodplains more than 200 kilometers downstream. Sieved sediment samples (<63µm) have been collected at 10 stations along a 200 kilometer contamination gradient annually since 1996. Ongoing remediation activities in the upper...
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This GIS dataset is the primary data product produced for the NW Climate Science Center-funded project, "Rangewide climate vulnerability assessment for threatened Bull Trout" (FRESC Study ID 851). We used predictions of temperatures in streams across approximately two-thirds of the species' range in the U.S. to map coldwater streams or “patches” suitable for spawning and early rearing of Bull Trout. Each patch consists of streams with contiguous reaches of cold water. Patches were delineated using medium resolution National Hydrography Dataset streams containing modeled temperatures available at 1 km intervals, as provided by the NorWeST project (http://www.fs.fed.us/rm/boise/AWAE/projects/NorWeST.html).Once the...
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Legacy mine waste from the Clark Fork River in Western Montana has contributed 100 million tons of tailings into the watershed between 1880 and 1982 (E.D. Andrews, Longitudinal dispersion of metals in the Clark Fork River, Montana, Lewis Publishers, 1987). Tailings deposited along the floodplain, streambanks and river channel continue to contribute metal contaminated material into the river in the form of metal-enriched particulate matter or seston, comprising a mixture of organic and inorganic materials (J.N. Moore and S.N. Luoma, Hazardous wastes from large-scale metal extraction: A case study. Environmental Science and Technology, v.24:1278-1285, 1990). Metal enriched seston poses a dietary exposure risk to filter-feeding...
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The U.S. Geological Survey monitored algal biomass accrual and concentrations of metals and other trace elements in stream water and periphytic algae at 3-4 day intervals over a 2-week period at 3 locations within the upper and middle portions of the mining-impacted Clark Fork River, Montana, and at one location on the relatively unimpacted Blackfoot River tributary. This data release makes available trends in major and minor trace element concentrations in surface water and periphytic algae, and corresponding trends in concentrations of autotrophic (chlorophyll a) and heterotrophic (ash-free dry mass) algal biomass collected in late July and early August 2015.
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Scouring of streambed material surrounding bridge structures is a leading cause of bridge failure in the United States. Damages resulting from bridge failure oftentimes lead to financial burdens and loss of life. To date, there has been no comprehensive evaluation of the current (2016) effectiveness of the guidance or overall long-term performance of bridge-scour countermeasures provided in the Federal Highway Administration, Hydraulic Engineering Circular No. 23, Bridge Scour and Stream Instability Countermeasures. To that end, the U.S. Geological Survey, in cooperation with the Federal Highway Administration, obtained bathymetric, topographical, and other data at 14 of the surveyed sites across the United States...
Bioaccumulated toxic metals in tolerant biomonitors are indicators of metal bioavailability and can be calibrated against metal-specific responses in sensitive species, thus creating a tool for defining dose–response for metals in a field setting. Dose–response curves that define metal toxicity in natural waters are rare. Demonstrating cause and effect under field conditions and integrated chemical measures of metal bioavailability from food and water is problematic. The total bioaccumulated metal concentration in any organism that is a net accumulator of the metal is informative about metal bioavailability summed across exposure routes. However, there is typically no one universal metal concentration that is indicative...
    map background search result map search result map Stream patches of suitable Bull Trout habitat and associated patch variables Geospatial Data for Bridge Scour Countermeasure Assessments at Select Bridges in the United States, 2014–16 SiteID-017 Clark Fork River at Turah Rd near Bonner, MT Biomass accrual and trace-element concentrations in water and periphytic algae at select locations in the Clark Fork and Blackfoot Rivers, Montana, 2015 Heatmap visualizations of arsenic, cadmium, and copper concentrations in streambed sediment in the Clark Fork River, Montana, 1996-2020 Metal concentrations in seston and water in the Clark Fork River, MT SiteID-017 Clark Fork River at Turah Rd near Bonner, MT Biomass accrual and trace-element concentrations in water and periphytic algae at select locations in the Clark Fork and Blackfoot Rivers, Montana, 2015 Heatmap visualizations of arsenic, cadmium, and copper concentrations in streambed sediment in the Clark Fork River, Montana, 1996-2020 Metal concentrations in seston and water in the Clark Fork River, MT Stream patches of suitable Bull Trout habitat and associated patch variables Geospatial Data for Bridge Scour Countermeasure Assessments at Select Bridges in the United States, 2014–16