Navajo Lake and Cedar City water supply

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HYDROLOGY AND HYDROGEOLOGY OF NAVAJO LAKE, KANE COUNTY, UTAH C9 TABLE 2.-Observed flow from Navajo Sinks to various springs A. Time of travel Navajo Sinks Date of test Sink Cascade Spring Time lapse, hours Until spring flow increased Until dye appeared Duck Creek Spring Time lapse, hours Until spring flow increased Until dye Lower Asay Spring Time lapse, hours Until spring flow increased 1954 Aug. 2-7 Aug. 12-17 Aug. 18-26 Do Sept. 3-4 Sept. 5-7 Sept. 8 All 1,2 1 2 3 2 1 1.0 1.0 1.0 0) 12 1.7 2.0 1.9 0) 5 9.5 9.8 12.5 19.0 32 12 15 18 53 53 53 40 40 50 52 Navajo Sinks Date of test Aug. 2-7 1954 Aug. 12-17 Do Aug. 18-26 Sept. 3-4 _ _ Sept. 5-7 June 17 1955 B Sink All 1 2 1,2 3 2 All Inflow vs. outflow Inflow (cfs) 10.4 3.21 7.9 4.7J 8.3 3.4 3.4 10.0 Increase in outflow, from recession curve Cascade Spring Cfs 2.8 2. 1 2.5 1.4 1.5 2.5 Percent 27 27 30 41 44 25 Duck Creek Spring Cfs 5.0 3.4 4.4 3.8 Percent 48 43 53 38 Lower Asay Spring Cfs 3.0 2.0 3 0 3 0 1 Test made without dye. DUCK CREEK SINKS Two small ponds have been developed by the U.S. Forest Service for recreation along Duck Creek-Duck Creek pond at the spring and Aspen Mirror Lake about 1% miles downstream. For the test of Duck Creek Sinks, dikes were placed in the overflow outlets which raised the water level about 1 foot in each pond. Stor­age of this extra water, estimated at 12 acre-feet, began August 18, 1954; the effect at the Duck Creek gaging station (below the Duck Creek pond) was an immediate reduction of flow from 9 cfs to less than 2 cfs and subse­quent recovery to 9 cfs within 54 hours. The flow of Asay Creek began to diminish 8 hours after the begin­ning of impoundment of the extra water and decreased about 3 cfs before starting to recover. On August 24, the extra water was released from Duck Creek pond, and as that water reached Aspen Mirror Lake, the water impounded there was also re­leased. This water reached Duck Creek Sinks at 3:40 p.m. The discharge of Asay Creek began to increase 9 hours later. As the extra water reached Duck Creek Sinks, iy2 pounds of dissolved fluorescein dye was poured into the sinks. The dye first appeared in Lower Asay Spring about noon of August 28 (a travel time of 68 hr) and the spring was markedly colored the next day; however, there was no evidence of dye in the Upper Asay Spring or in the springs along West Fork Asay Creek. It is concluded that the increased flow of Asay Creek resulted entirely from increased discharge from the Lower Asay Spring; however, the Duck Creek Sinks are not the sole source of water in the Lower Asay Spring, for the latter had a discharge five times as great as the inflow to Duck Creek Sinks just prior to the arrival of the extra water. WATER QUALITY The water of Navajo Lake has a markedly higher summer temperature and generally contains less dis­solved mineral matter than water issuing from the springs at lower elevations which were sampled for