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The National Weather Service predicted another above-average spring runoff, but less than the flows in 1983 or 1984. The Bureau of Reclamation lowered all reser- voirs to develop reservoir space to con- lain the expected runoff of 123 percent of normal. The June-July forcast for inflow to lake Powell was 4.8 million acre-feet. or 160 percent of normal. Snowmelt within the mountains of the Upper Colorado Basin resulted in a higher than normal flow from Colorado and New Mexico and lower than normal flow from Utah and Wyoming When the runotf season ended, nearly 15 million acre-feet, or 202 percent of nor- mal had flowed into lake Powell. The lake elevation reached 3,702 in July, which is 2 feet above the normal full elevation. Fontenelle Dam, located on the Green River about 59 miles north of the city ot Green River. WY. has had an extensive array of monitoring inslruments and survey points installed to detect the seepage paths in, under. and around the earth-filled darn Serious seepage damage, apparently through the rock foundation under the darn, was documented by Reclamation engineers and geologists during 1983 and 1984 Independent consultants. R.W. Beene and Ralph P. Peck. were Iwed and thell report. released in January 1985. concur- red with Reclamation.s proposals to stop the seepage. Tiley also recommended a concrete core wall through the embank- ment and Into the foundaflon 01 the mlle- long struclure. Two lest sections of the core wall, tolal- Ing 850 leet long, one around the spillway and one near the east abutment of Ihe dam. were to be constructed to prove the englneerrng Viability of Ihe proposed core wall stucture. to assess detailed construc- tion melhods. and to determine costs for preparation at a cost estimate for the en- tire project 2 Fonlenelle Dam. Sedskadee Project In April, while awaiting contract funding, an area of known seepage unexpectedly registered high readings on two water pressure monitoring devices located near the center of tile dam. Reclamation officials had initially planned to draw the reservoir down '/2 foot per day for 3 or 4 months. Wanting to take no chances on the safety of human lives and property below the dam, a decision was made to increase the releases trom the dam. On May 1 and 2. releases were increas- ed in increments of 1,000 cubic feet per second (cis) until the releases reached about 12,000 cfs, which is less than the capacity of the Green River below the Dam. When the level of the reservOir dropped to elevation 6,4 75 feet above sea level, the 13-megawatt powerplant was shut off from its water supply and ceased opera- tions. The Colorado River Storage Project replaced that power promptly so resi- dents of Bridger Valley had thei r power needs met. lowering the reservoir reduced the water pressure readings on the instrumentation at the dam. On May 8, with the reservoir at elevation 6,451, releases were cut back to 7,600 cfs. Draining ot the reser- voir to elevation 6,435 was planned. How- ever, to maintain both minimum down- stream releases and a minimum reservoir pool, the reservOIr was kept at 6.443 teet. Releases were maintained about the same as the inflows. The reservOir con- tained only 32,900 acre-feet of water out of a full capacify of 343,400 acre-feet at elevation 6,505. In May, a $4.7 million construction con- tract was awarded tor two test sections. The contractor, RECOSOl, Inc, was re- quired to place 210 linear feet of wall in 1985, and was able to place 250 feet betore cold weather forced them to stop work. Placing ot the remaining 600 feet of test wall is expected to resume in the spring of 1986.