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Show Chapter 2 Watershed Characteristics and Uses DISSOLVED METALS & PHYSICAL DATA Dissolved metals ( corrected for water hardness) and physical data ( see Appendix J) for each canyon were compared with state water quality standards. No exceedences were found when comparing with use classification IC ( protected for domestic use with prior treatment). A summary of the results of a comparison of dissolved metals and physical data with cold water fishery use classification ( 3A) standards is provided on Table 9. Often lab analyses for lead and silver have been with a detection limit higher than the criteria for cold water fishery Table 9 Dissolved Metals And Physical Data Exceedences of State Water Quality Standards For 3a Co d Water Fishery Use Classification CANYON Exceedences City Creek None Emigration Canyon None Parleys Canyon None Millcreek None Big Cottonwood Creek None Little Cottonwood Creek Copper: 5/ 15/ 96, 7/ 11/ 96; Lead: 7/ 11/ 96 4- day average criteria used, ok for 1- hour average; Zinc: 5/ 15/ 96 and 7/ 11/ 96 SUMMARY AND CONCLUSIONS 1. Canyon water quality is generally excellent, especially for drinking water source purposes. However, mean annual total coliform counts increased significantly in 1995 in City Creek, Big Cottonwood Creek and Little Cottonwood Creek ( see Figure 1 in Appendix J). 2. The increase in total coliform counts does not correspond to an increase in fecal coliform. The reasons for the increase in total coliform are not found in the data. Page 24 |