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tune. Constituents in high-altitude lakes shoal
<br />improving trends iii chloride, iron, and pH.
<br />Constituents ili Vallecito Creek upstream from
<br />Vallecito Reservoir shoal improving trends in chloride,
<br />ammonia, gross beta radioactivity, and pH. The
<br />improving trends are statistically significant; ho~yever,
<br />the causes for the improving trends are unlcno~~m.
<br />Water-quality data from Los Pinos River below
<br />Vallecito Reseivoi<- shows the effects of the
<br />Missionan- Ridge wildfire. Specific conductance
<br />values, pH, and nitrite+nitrate concentrations have
<br />increased in ~~ ater do~~nstream from the dam.
<br />Water-quality data from Vallecito Reservoir
<br />sho~y some impacts from the Missionai-~~ Ridge
<br />~yildfire of 2002. Specific conductance values have
<br />increased since the wildfire, and dissolved-oi~-gen
<br />concentrations were as low as 0.3 mg/L, resulting in a
<br />fish kill of kokanee salmon iii the lake during August
<br />2003. However, dissolved-oiygen concentrations also
<br />~yere as low as 0.3 mg/L during September 2000, and
<br />no fish were killed during that event. There may be
<br />other factors involved ~yith the fish kill of 2003, such
<br />as lncreased rroll and manganese COricentratlollS due t0
<br />sediment runoff from the wildfire and anaerobic
<br />conditions created by runoff of organic matter. Water-
<br />quality samples for analysis of dissolved metals have
<br />not been collected in Vallecito Reservoir since 2000;
<br />therefore. it is difficult to conclude the impacts of the
<br />wildfire on the lake ecosVStem.
<br />Compai7son of historical water-quality data to
<br />water-quality standards indicates that most of the
<br />~yaters in the upper Los Pinos River watershed meet
<br />the standards. A fey constituents were sho~tin to
<br />eiceed the standards in a fey locations--such as
<br />ammonia, total iron, pH, total phosphorus, selenium,
<br />zinc, and fecal colifonn in streams and ground water
<br />in the Vallecito Reservoir area. Dissolved-oivgen
<br />concentrations in the reservoir ~yere below the
<br />standards of 6.0 mg/L.
<br />This report provides limited interpretations of
<br />~yater-quality data. Suggestions for development of a
<br />watershed plan are provided. Development of a
<br />watershed plan requires input from the community.
<br />agencies, and tribes. The goal of this effort is to
<br />present the data to the public through distribution at
<br />meetings, and to stimulate dialog towards community-
<br />based ~yatershed planning. Suggestions also are made
<br />in this report for continued ~yater-quality- monitoring.
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<br />Turk. J.T., Campbelh D.H., and Spahr. N.E. 1993, Use of chenrishy~
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<br />Resources, 1979. Los Pirios River, Draft Environmental Statement
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<br />fish and y~Yldlife resources in relation to the eiisting Pine Rig°er
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