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Show During the period of July 1980 through October 1982, the U. S. Geological Survey, in cooperation with the Salt Lake County Division of Flood Control and Water Quality, conducted a study of Jordan River water quality. The study focused on the following four areas: sanitary quality, toxic substances, dissolved oxygen and turbidity. The following summarizes the findings: Sanitary Quality - Data collected from July 1980 through October 1982 showed a serious sanitary problem in the Jordan River. Concentrations of total coliform bacteria commonly exceeded 5,000 colonies per 100 milliliters and concentrations of fecal coliform bacteria commonly exceeded 2,000 colonies per 100 milliliters in downstream reaches of the river. The most conspicuous aspect of the bacteriological data was its extreme variability. Because of the variability, the sanitary quality of the Jordan River cannot be predicted at any given time. More recently acquired data indicates the sanitary conditions are unchanged with respect to fecal coliform and total coliform counts. Two wastewater treatment plants, seven major tributaries, numerous storm drains, irrigation- return flow and other sources all contribute to the dynamic system that determines the sanitary quality of the Jordan River. In general, concentrations of all three indicator bacteria increased in a downstream direction. The ratio of fecal coliform to fecal streptococci concentration indicated contamination from animal waste in 92 percent of the samples from the Jordan Narrows. Contamination from human waste was indicated in none of the samples at the Jordan Narrows and 90th South, but increased to 20 percent of the samples at 1700 South Street. But human sewage in many of the samples may be camouflaged by large concentrations of fecal streptococci bacteria. With the exception of copper and zinc, concentrations of trace elements in bottom materials in Little Cottonwood, Big Cottonwood and Mill creeks were similar to concentration levels in the Jordan River downstream sampling sites. At the present time, the Environmental Protection Agency, jointly with Kennecott Utah Copper and Sharon Steel, is conducting a superfund cleanup project to remove and dispose of mining tailings from the Bingham Creek channel, the Sharon Steel mine and mill site and surrounding lands in Midvale. This effort could have a significant impact on reducing the heavy metals concentrations in the Jordan River. Dissolved Oxygen - Dissolved oxygen depletion in the Jordan River was identified as a major problem by two- thirds of the federal, state and local agencies responding to a request from the U. S. Geological Survey for comments on the study. Depletion of the dissolved oxygen concentrations to less than 5 to 6 milligrams per liter adversely affect fishery populations, benthic organisms and the natural oxidation of organic substances in the water. The intent of the study was to provide sufficient data and interpretation to understand the dissolved oxygen regime of the Jordan River. The study accomplished the following goals: 1) Historical data were tabulated and compared to current data to determine trends, 2) re- aeration rates and time- of- travel were determined for the Jordan River from 12300 South to 1800 North Streets, 3) algal productivity and its impact in the downstream part of the river ( north of 5800 South Street) were calculated, and 4) loads of oxygen- demanding substances from storm runoff and wastewater treatment plants were determined. The study concluded mean concentrations of dissolved oxygen decreased from 8.1 milligrams per liter at the Jordan Narrows to 4.7 milligrams per liter at 500 North Street during April 1981 to September 1982. Coincident with the decrease, the biochemical- oxygen demand increased from 5 to 7 milligrams per liter. About 50 percent of the dissolved oxygen concentrations and 90 percent of the five- day biochemical- oxygen demand measured downstream from 1700 South Street exceeded the state intended- use standards. An estimated 6 million pounds of oxygen- demanding substances, as measured by the five- day biochemical- oxygen demand, were discharged to the Jordan River during 1981 from point sources downstream from 9000 South Street. Wastewater treatment plants contributed 77 percent of this load, non- storm base flows contributed 22 percent, and storm flows less than 1 percent. The Surplus Canal diversion at 2100 South Street removed about 70 percent of this load, and travel time of about one day also decreased the actual effects of the load on the river. Turbidity - Samples were collected at five sites on the Jordan River from January 1981 through August 1982 and analyzed for turbidity, suspended sediment concentration, suspended organic carbon and other properties. Correlation coefficients ranging from 0.71 to 0.83 indicated significant relationships 12- 9 |
