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Show Salt Lake City Watershed Management Plan ' 99 Table 5 TOTAL COLIFORM STATIST CSSUM MARY CANYON/ Monitoring Station Period of Coverage Mean Standard Deviation Number of Samples BIG COTTONWOOD CREEK Treatment Plant Intake BC1 - USFS Boundary 1960- 1997 1988- 1997 36.6 38.1 39 52 453 221 LITTLE COTTONWOOD CREEK Treatment Plant Intake LC1 - USFS Boundary 1960- 1997 1988, 1990- 1997 19.5 33.8 21 35 449 72 TREATMENT PLANT RAW WATER INTAKE TOTAL COLIFORM DATA There are two higher trends in mean annual total coliform shown on Figure 1 found in Appendix J, one during the early 1970' s and the other in 1995. Coliform counts were lower than normal for the period 1991 through 1994, then increased to above normal in 1995. Years with significantly higher means ( Students t test14) are summarized in Table 6. T Treatment Plant Ra Years With Signil able 6 tw Water Total Coliform ficantly Higher Means Treatment Plant Years with Significantly Higher Means ( based on Student's t test with 95 percent probability) City Creek 1970,1971,1972 and 1995 Big Cottonwood Creek 1970,1971,1972, and 1995 Page 21 |