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<br /> <br />In addition to the two reservoir sites, the U.S. Geological Survey <br />streamflow-gaging station 09306290, White River below Boise Creek, near <br />Rangely was established as site 3. Site 3 is about 8 mi upstream from Kenney <br />Reservoir (fig. 2). All hydrologic data used in this report were obtained <br />from the U.S. Geological Survey WATSTORE (Hutchison, 1975) computer data base. <br /> <br />Profile measurement~ of water-quality properties and constituents and <br />sample collections for chemical, biological, and physical analyses were made <br />in the reservoir using a submersible pump that continuously delivered water <br />from any depth to a multiprobe manifold at the water surface. The manifold <br />housed probes that measured temperature, specific conductance, pH, and dis- <br />solved oxygen. Water samples could be withdrawn at any depth for laboratory <br />analysis. Except at the manifold discharge point, water movement within the <br />entire system remained isolated from atmospheric effects. Oxygen consumption <br />because of indigenous processes that occur within the reservoir (sites 1 and <br />2) and in the White River (site 3) were estimated from 5- and 20-day natural <br />biochemical-oxygen-demand (BOD) analyses. Incubations for the BOD analyses <br />were processed from iced samples within 12 hours of sample collection. <br /> <br />Light penetration in the reservoir was measured using a standard Secchi <br />disk. The average extinction depth of several observations was used. This <br />value approximates the depth that receives 5 percent of the surface light <br />intensity (Yoshimura, 1938). Major zones in a lake or reservoir based on a <br />combination of light penetration, biology, and morphology are shown in <br />figure 3. <br /> <br />Assessments of general water chemistry are based on laboratory data for <br />periodic samples of major constituents, nutrients, and trace constituents. <br />Samples were taken from near-surface and near-bottom depths at sites 1 and 2 <br />in the reservoir and from depth composites at site 3 in the White River. <br /> <br />Point samples for phytoplankton (algae) identification, biomass, and <br />chlorophyll analyses were collected from depths of maximum dissolved-oxygen <br />saturation (usually 2 ft). Because oxygen is a by-product of photosynthesis, <br />data from these depths generally should represent zones of maximum phyto- <br />plankton activity. A second sample that consisted of a composite of water <br />from the euphotic zone (fig. 3) at site 1 and the general water column at <br />site 2 also were analyzed. These analyses were done to describe the general <br />phytoplankton population in the reservoir. The base of the euphotic zone <br />generally is estimated by multiplying the Secchi-disk depth by a factor of 2.5 <br />to 5.0 (Verduin, 1956). However, factors that ranged from 3.0 to 6.0 at <br />site 1 were used where Secchi-disk depths were between 20 and 40 in., and <br />factors that ranged from 2.0 to 4.0 were used where Secchi-disk depths were <br />greater than 40 in. Samples, from water surface to a depth of 10 ft at <br />site 1, were composited when Secchi-disk depths were less than 20 in. All <br />phytoplankton and chlorophyll samples were analyzed by a private laboratory. <br />Concentrations of chlorophylls a, b, and c were determined except where large <br />concentrations of suspended material interfered with the analyses. <br /> <br />The presence of sanitary-indicator bacteria, total and fecal coliform, <br />and fecal streptococci also were determined during 1985-86 from near-surface <br />and near-bottom depths at both sites in Kenney Reservoir. Incubations for the <br />bacteria analyses were processed from iced samples within 12 hours of sample <br />collection. All samples for chemical and biological laboratory analyses were <br /> <br />8 <br />