Year: 1984
Type: report
Abstract: Water-quality studies were made on the Jordan River, Salt Lake County, Utah, from 1980-82 to investigate specific problems involving dissolved oxygen, toxic substances, sanitary quality, and turbidity.The studies were coincident with an investigation of the affects of urban runoff on surfacewater quaility in Salt Lake County.The combination of large organic loads, small discharge, and slight reaeration rates resulted in dissolved-oxygen concentrations in the Jordan River downstream from 5800 South Street during April-September which frequently did not meet State intended use standards.The dissolved oxygen typically decreased from about 8 milligrams per liter at the Jordan Narrows to less than 5 milligrams per liter at 500 North Street.Accompanying this decrease was an increase in chemical-oxygen demand of about 23 percent and in biochemical-oxygen demands of 90 percent.An estimated load of 6 million pounds of oxygen-demanding substances was discharged to the Jordan River annually from point sources north of 9000 South Street.Wastewater-treatment plants contributed 77 percent of these substances, nonstorm base flows from the major tributaries to the river contributed 22 percent, and storm flows contributed less than 1 percent.Most of the organic substances were discharged to the reaches characterized fcy the smallest reaeration rates.A diversion to the Surplus Canal removed 67 percent of the oxygen-demanding substances in the river.Several toxic substances, primarily trace metals, were detected in the Jordan River and its major tributaries.Nearly 78 percent of the water samples analyzed for total mercury exceeded the State intended-use standard of 0.05 microgram per liter.Concentrations of five other toxic substances exceeded the standards occasionally: ammonia (18 percent of the samples); cadnium (9 percent); copper (9 percent); lead (2 percent); and zinc (6 percent).The concentrations of trace elements found in bottom sediments increased markedly at 5800 South Street and persisted downstream to 500 North Street.The pesticides DOT, DDD, DEE, dieldrin, methoxychlor, and 2,4-D were detected in bottom materials, but most were at concentrations less than 15 micrograms per kilogram.Bottom samples from the Jordan Narrows contained KB concentrations as great as 320 micrograms per kilogram.Samples were collected from three conduits during a storm on October 29, 1981, and analysed for priority pollutants as designated fcy the U.S. Environmental Protection Agency.Trace metals were identified as common contaminants, but only 2 of the 113 organic pollutants (chloroform and phenol) were detected.The concentrations of bacteria in the Jordan River often exceeded the State sanitary standards for total coliform bacteria (5,000 colonies per 100 milliliters) and for fecal coliforms (2,000 colonies per 100 milliliters).Concentrations of three indicator bacteria (total coliform, fecal coliform, and fecal streptococcal) generally increased in a downstream direction.Contamination from animal waste was indicated in 92 percent of the samples
DOI: 10.3133/wri844298
Author: D. W. Stephens
Language: English
Subfield: Water Science and Technology
Field: Environmental Science
Domain: Physical Sciences
Open Access status: gold
OpenAlex ID: W134069955