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<br /> <br />Data for onsite measurements of temperature, specific conductance, pH, <br />and dissolved oxygen were collected continuously with depth at sites 1 and 2. <br />Data for these profiles are presented for selected depths in tables 11 and 12 <br />in the "Hydrologic Data" section at the back of the report. In addition, <br />selected water-quality data for near-surface (2 ft) and near-bottom depths at <br />sites 1 and 2 are listed in tables 13 and 14 in the "Hydrologic Data" section. <br /> <br />Temperature <br /> <br />Water temperature from profiles in Kenney Reservoir (tables 11 and 12 in <br />the "Hydrologic Data" section) ranged from 0 oC during winter to 23.8 oC at <br />site 1 during summer, and the maximum water temperature was 24.4 oC at site 2 <br />during summer. Measurements of water temperature for selected depths at <br />site 1 are shown in .figure 6. During water years 1985-87, measured water <br />temperatures in the White River at site 3 ranged from 0 to 24.0 oC. Although <br />these data represent instantaneous measurements in time and cannot be compared <br />directly, it seems that the range in temperature of the near-surface water in <br />the reservoir and the White River at site 3 were similar. <br /> <br />During summer, water temperature at site 1 generally decreased 3 to 5 oC <br />with depth (fig. 6). Because water density increases with decreasing water <br />temperature for temperatures above 4 oC, some thermal stratification developed <br />in the reservoir from May through September during the study period. The <br />possible causes for the decreases in temperature with depth were: <br /> <br />1. The disproportionately large absorption of solar radiation by near- <br />surface water when compared with the decreased penetration and absorption <br />of solar radiation by water at depth; and <br /> <br />2. The routing of inflow water within the reservoir to depths or zones that <br />had water temperature similar to the existing temperature of the inflows. <br />Thus, inflow from the White River that enters the reservoir in the early <br />morning, when stream temperatures are cool compared with afternoon tem- <br />peratures, may remain and pass through the reservoir at depth. <br /> <br />The temperature differences that develop between near-surface and near- <br />bottom water in the reservoir, the time that stratification stability exists <br />during summer, and the warming of near-surface water may be expected to <br />increase as inflow to the reservoir decreases and as the residence time of the <br />inflowing water increases. <br /> <br />Specific COnductance <br /> <br />Specific conductance is a measure of the ability of water to conduct an <br />electric current and is reported in microsiemens per centimeter at 25 degrees <br />Celsius. Specific conductance can be used to estimate the dissolved-solids <br />concentration of similar water types (Hem, 1985, p. 67). Chemical, hydro- <br />logical, and biological activities continuously alter specific conductance <br />through chemical solution or precipitation, dilution and evaporation, and <br />metabolic uptake and release of chemicals. <br /> <br />14 <br />