Show Colorado River Should Restore Lake Mead A forecast l. l t of 9 million acre acre- t as the mo most t likely runoff the Under Colorado River ring the coming Ap r I 11 I ough July season Id Id mean If It the actual run rum ff f lives up tip to early Ins ns that Lake Mead could be to its rated power ele ele- Ion by the end of next July q Bureau of Reclamation d d 1 this week RECLAMATION I a I s i ed ed cd heavily on the if U In Ir ir statement explaining that any factors could cause drassic drasIc dras dras- sic Ic changes In a forecast based only on above average precipitation this early in the water year The forecast of 9 0 million f feet acre et is merely the most likely April July April July runoff to be expected provided precipitation tion during the rest of the winter win ter and early spring holds up to the term long-term average There Is about an even chance of a runoff on the Colorado River of somewhere between and feet acre-feet during he e four month sea sea sea- son ion with 9 million being the best forecast at the present time SHOULD THE TilE 9 million acre acre acre- feet of runoff actually occur on schedule then reclamation officials officials of are arc confident Lake Mead could be returned to its rated power elevation of 1123 feet sometime during July This Is 35 feet higher than its present level If It the present forecast actually actually ac ac- ac materializes into 9 million mil mu- lion feet acre of water during the July April season indicating indicating ing a total Colorado River runoff runoff run run- off of about feet acre-feet during 1965 the following circumstances circumstances cir cir- would appear reasonable reasonable rea rea- as far as operations of the Colorado River Storage Project reservoirs are concerned concerned con con- LAKE LAI Powell Glen Canyon would be held slightly above feet elevation the minimum mini mint mum level at which the Glen Canyon can be kept in pr production All of the spring runoff would be passed downstream downstream down down- stream to swell Lake Mead Flaming Gorge Reservoir levels would continue to fall slowly until April 1 to about elevation feet due to continued continued continued con con- maximum power tion At this level the reservoir would be feet deep at the dam WATER released through the Flaming Gorge generators Is also released through the Glen Canyon generators with any excess above turbine capacity released through the gates in order to keep Lake Mead above the minimum generating elevation elevation elevation eleva eleva- tion of 1083 1053 feet during the critical critical crit crit- ical low-flow low wint winter r season Providing the runoff keeps pace with the forecast the reservoir reservoir reservoir res res- would be ral raised railed ed to about elevation with water content content con con- tent of feet acre during July and August Navajo Reservoir stood at elevation elevation el el- el feet on Jan 1 I with feet acre of water in storage The level of the reservoir reservoir reser reser- voir must be lowered to about feet acre of storage by April 1 to keep the April through July runoff from flooding flooding flooding flood flood- ing work in progress on the diversion di diversion version tunnel inlet for the Navajo Indian Irrigation BY DY THE TIIE LATTER part of May the reservoir level will rise rapidly to feet acre again granting that the forecast forecast forecast fore fore- cast runoff materializes and will remain above that level during the summer months Lake Mead dropped below its rated operating head 1 last a s t spring when it was decided to fill Lake Powell to Its minimum minimum mini mini- mum power pool so that generation generation gen gen- i at the Glen Canyon could begin on schedule last September Three generating units are now In o operation operation op op- p at Glen Canyon and a fourth Is h scheduled t to go on th theline the theline e line before the spring runoff be gins These four can pass u uto up p to cubic feet of water per second to the river below AN APRIL through July runoff run rum off of 9 million feet acre would woul d be the Ule first average above-average water water wa wa- ter yield from the Colorado River River Riv er watershed In three years It would exceed the long time average average av avo av- av by acre feet acre feet and would be 35 million feet acre more than the runoff for the same samo samp period last year and 57 million feet acre-feet greater than the near record low of 1963 This years year's spring runoff forecast indicates a total runoff run off oft of about million acre acre- feet for 1965 |