OCR Text |
Show Colorado River Runoff Above Normal After Heavy Winter Snowfalls February's moderately heavy hea-vy precipitation in the mountainous moun-tainous Upper Basin of the Colorado River has raised spring to 9 million acre-feet, or 1C6 per cent of normal, the Bureau of Reclamation announced Wednesday. This forecast is up slightly from the 8.8 million acre-feet predicted pre-dicted a month ago. Longtime Long-time average runoff is 8.5 million acre-feet for the April-July runoff period. If the amount forecast is realized, Lake Powell above Glen Canyon Dam should rise to about elevation 3,587 feet above mean sea level with 12.9 m.a.f. of live storage stor-age by mid-summer. The lake should remain near this level during the summer and into winter. The planned releases re-leases from Lake Powell for water year 1969 will be near 8.8 m.a.f. For the next three years thereafter, annual releases re-leases should be near this amount in order to fulfill the Colorado River Compact requirement re-quirement of delivery of 75 m.a.f. to the Lower Basin in the 1963-72 decade. Power loads should be adequate to utilize these larger releases during the 1969-72 period. About 1.2 m.a.f. of runoff should originate above Flaming Flam-ing Gorge Dam, or 105 per cent of normal. Of this amount, am-ount, about 200,000 acre-feet will be stored in Fontenelle Reservoir. The remainder will flow into Faming Gorg.? Reservoir, raising its level from 5,975 feet above mean sea level at present to 5,987 early in July. This small rise and subsequent slow descent de-scent still assure a stable lake for recreation purposes this summer. About 1 million acre feet of runoff is expected to occur oc-cur above Navajo Dam on the San Juan River, 960,009 acre-feet above Fontenelle Dam on the Green River, and 830,000 acre-feet above Blue Mesa Dam on the Gunnison Gun-nison River. These forecasts are all above normal snow-melt snow-melt runoff. All major reservoirs res-ervoirs located upstream from Lake Powell should have a seasonal rise in their water levels; however, the major portion of the 9 m.a.f. will flow into Lake Powell. Lake Mead on March 1 was at elevation 1141 feet above m.s.l., or about 8 feet higher than a year ago. It contained 15.5 m.a.f. of available avail-able storage, or 57 per cent of its capacity. The reservoir reser-voir level was 81 feet below the top of the raised spillway spill-way gates u Hoover Dam. The lake is expected to remain re-main near this level or ri.S'.; slowly another foot through next June. Levels of the reservoir res-ervoir after then will depend on the amount of runoff received re-ceived from the watershed. |