Water quality in the Puget Sound basin, Washington and British Columbia, 1996-98

Ebbert, J.C.; Embrey, S.S.; Black, Robert W.; Tesoriero, Anthony J.; Haggland, Alan L.

doi:10.3133/cir1216

Cited by 12 publications

(5 citation statements)

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“…The sites with the highest median E. coli concentrations were the four sites on the Merced River in and below Yosemite Valley (excluding HAPI), and SFWC and SFKB on the South Fork of the Merced. These sites are in areas receiving high visitor-use or are downstream from substantial For comparison, measured concentrations of E. coli at sites downstream from developed areas were within the range observed at undeveloped sites, and were substantially below those observed at urban, agricultural, and rural sites in several previous USGS studies (Ebbert et al 2000;Hoos et al 2002). No samples exceeded the USEPA single-sample standard for E. coli of 235 MPN/100 ml for moderate recreational contact (U.S. Environmental Protection Agency 1986).…”

Section: Current Conditions and Spatial Patterns In Nutrient And E Cmentioning

confidence: 58%

Assessing possible visitor-use impacts on water quality in Yosemite National Park, California

Clow

Peavler²,

Roche

et al. 2011

Environ Monit Assess

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There is concern that visitor-use associated activities, such as bathing, dish washing, wastewater production, and stock animal use near lakes and streams, could cause degradation of water quality in Yosemite National Park. A study was conducted during 2004-2007 to assess patterns in nutrient and Escherichia coli (E. coli) concentrations in the Merced and Tuolumne Rivers and characterize natural background concentrations of nutrients in the park. Results indicated that nutrient and E. coli concentrations were low, even compared to other undeveloped sites in the United States. A multiple linear regression approach was used to model natural background concentrations of nutrients, with basin characteristics as explanatory variables. Modeled nitrogen concentrations increased with elevation, and modeled phosphorus concentrations increased with basin size. Observed concentrations (±uncertainty) were compared to modeled concentrations (±uncertainty) to identify sites that might be impacted by point sources of nutrients, as indicated by large model residuals. Statistically significant differences in observed and modeled concentrations were observed at only a few locations, indicating that most sites were representative of natural background conditions. The empirical modeling approach used in this study can be used to estimate natural background conditions at any point along a study reach in areas minimally impacted by development, and may be useful for setting water-quality standards in many national parks.

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Section: Current Conditions and Spatial Patterns In Nutrient And E Cmentioning

confidence: 58%

Assessing possible visitor-use impacts on water quality in Yosemite National Park, California

Clow

Peavler²,

Roche

et al. 2011

Environ Monit Assess

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“…Surface water monitoring studies in salmon habitats [3–8] have generally detected anticholinesterase insecticides at concentrations that are well below those likely to cause acute fish kills (i.e., median lethal concentrations for rainbow trout). Consequently, from a natural resource management perspective, there are two primary concerns for salmonids.…”

Section: Discussionmentioning

confidence: 99%

“…The distribution and biological requirements of listed species are therefore important considerations for ecological risk assessment, as is the condition of the different ecosystems that support salmon. Because pesticide mixtures are frequently detected in salmon habitats [3–8], assessments that focus exclusively on single chemicals might underestimate the actual risk to threatened and endangered species under real‐world exposure conditions. This is particularly true for the anticholinesterase insecticides, as well as other classes of pesticides that share a common mode of action.…”

Section: Discussionmentioning

confidence: 99%

“…For example, more than half of the surface water samples from certain agricultural drainages in California's Central Valley, USA, contained seven or more pesticides [3]. In California and the Pacific Northwest, USA, these general patterns of pesticide detections are typical of NAWQA monitoring investigations in the San Joaquin [4], Sacramento [5], Willamette [6], Yakima [7], and Puget Sound [8] basins.…”

Section: Introductionmentioning

confidence: 99%

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Dose‐additive inhibition of chinook salmon acetylcholinesterase activity by mixtures of organophosphate and carbamate insecticides

Scholz

Truelove

Labenia

et al. 2006

Enviro Toxic and Chemistry

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Organophosphate and carbamate insecticides are widely detected in surface waters of the western United States. These chemicals interfere with acetylcholine-mediated synaptic transmission in the nervous systems of fish and other aquatic animals via the inhibition of AChE (acetylcholinesterase) enzyme activity. Anticholinesterase insecticides commonly co-occur in the environment. This raises the possibility of antagonistic, additive, or synergistic neurotoxicity in exposed fish, including threatened and endangered species of Pacific salmon. We extracted AChE from the olfactory nervous system of chinook salmon (Oncorhynchus tshawytscha) and investigated the inhibitory effects of organophosphates (the oxon derivatives of diazinon, chlorpyrifos, and malathion) and carbamates (carbaryl and carbofuran), alone and in two-way combinations. We found that the joint toxicity of anticholinesterase mixtures can be accurately predicted from the inhibitory potencies of individual chemicals within a mixture. This indicates that organophosphate and carbamate insecticides are noninteractive in terms of AChE inhibition and that it might be possible to estimate the cumulative neurotoxicity of mixtures by simple dose addition. Because organophosphates and carbamates are likely to have additive effects on the neurobehavior of salmon under natural exposure conditions, ecological risk assessments that focus on individual anticholinesterases might underestimate the actual risk to salmon in watersheds in which mixtures of these chemicals occur.

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“…The Puget Sound basin encompasses 16 major river systems and many smaller independent streams that drain a total area of 35,500 km 2 (Ebbert, Embrey, Black, Tesoriero, & Haggland, ). The basin is bounded by the Olympic Mountains to the west and the Cascade Mountains to the east (Figure ).…”

Section: Puget Soundmentioning

confidence: 99%

Influences of valley form and land use on large river and floodplain habitats in Puget Sound

Stefankiv

Beechie

Hall

et al. 2019

River Research & Apps

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In this paper, we use a system‐wide census of large river and floodplain habitat features to evaluate influences of valley form and land use on salmon habitats along 2,237 km of river in the Puget Sound region of Washington State, USA. We classified the study area by geomorphic process domains to examine differences in natural potential to form floodplain habitats among valley types, and by dominant land cover to examine land use influences on habitat abundance and complexity. We evaluated differences in aquatic habitat among strata in terms of metrics that quantify the length of main channels, side channels, braid channels, and area of wood jams. Among geomorphic process domains, habitat metrics standardized by main channel length were lowest in canyons where there is limited channel migration and less potential to create side channels or braids, and highest in post‐glacial and mountain valleys where island‐braided channels tend to form. Habitat complexity was lower in glacial valleys (generally meandering channels) than in post‐glacial valleys. Habitat abundance and complexity decreased with increasing degree of human influence, with all metrics being highest in areas classified as forested and lowest in areas classified as developed. Using multiple‐year aerial photography, we assessed the ability of our methods to measure habitat changes through time in the Cedar and Elwha Rivers, both of which have recent habitat restoration activity. We were able to parse out sources of habitat improvement or degradation through time, including natural processes, restoration, or development. Our investigation indicates that aerial photography can be an effective and practical method for regional monitoring of status and trends in numerous habitats.

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Water quality in the Puget Sound basin, Washington and British Columbia, 1996-98

Cited by 12 publications

References 0 publications

Assessing possible visitor-use impacts on water quality in Yosemite National Park, California

Assessing possible visitor-use impacts on water quality in Yosemite National Park, California

Dose‐additive inhibition of chinook salmon acetylcholinesterase activity by mixtures of organophosphate and carbamate insecticides

Influences of valley form and land use on large river and floodplain habitats in Puget Sound

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