Methods of data collection and water-quality data for Standley Lake, Jefferson County, Colorado, 1989-90

Abstract

Physical, chemical, and biological water-quality data were collected and compiled for sites in Standley Lake, its primary inflows, and its outflow from June 21, 1989, to October 30, 1990. Data were collected to determine the limnological characteristics of Standley Lake and the processes that could affect nutrient availability, algal growth, and the occurrence and potential sources of compounds that cause taste and odor problems. These data include measurements of water temperature, pH, dissolved oxygen, and specific conductance in the lake and in the inflows and outflow. Light transparency also was measured in the lake. Lake water, inflow and outflow water, bottom sediment, and interstitial pore water periodically were analyzed for concentrations of nutrients and trace elements. Lake water also was analyzed for concentrations of chlorophyll a, densities and biovolumes of phytoplankton, and densities of zooplankton. Artificial and natural substrates from the lake were analyzed for periphyton density and biomass. The inflows were analyzed for densities and biovolumes of phytoplankton. R.71 W. 105' 3°15'R.70W. R69W. 3. Determine whether the availability of phosphorus limits algal growth during periods when algae suspected of causing taste and odor problems may be present in Standley Lake. 4. Determine the compounds responsible for taste and odor problems in the water delivered from Standley Lake and the potential sources of these compounds to water in the lake. Objectives 1-3 were accomplished by the U.S. Geological Survey. Objective 4 was accomplished by Drexel University, Philadelphia, Pa., using water and biota samples provided by the U.S. Geological Survey; results of this part of the study are presented in two reports from Drexel University (I.H. Suffet and Djanette Khiari, Drexel University, written commun., 1991; Patricia Cascallar and Wesley 0. Pipes, Drexel University, written commun., 1991). Purpose and Scope This report describes the methods of data collection and presents the physical, chemical, and biological data collected from Standley Lake, its primary inflows, and its outflow. Physical data include measurements of temperature, pH, dissolved oxygen, and specific conductance in the lake and in the inflows and the outflow. Transparency, or light penetration, also was measured in the lake. Chemical data include concentrations of nutrients and trace elements in the lake water, the inflows and outflow, the bottom sediment, and the interstitial pore water. Biological data include concentrations of chlorophyll a, densities and biovolumes of phytoplankton, densities of zooplankton, and densities and biomass of periphyton in the lake and densities and biovolumes of phytoplankton in the inflows. Samples were collected from several locations in Standley Lake, from three surface inflows to the lake, and from the outflow to the city of Westminster's Semper Water Treatment Plant. Sampling began on June 21, 1989, and concluded on October 30, 1990. Description of the Study Area f Standley Lake is located in the cit...