9416

• UCREFRP Catalog Number: 9416
• Author: U.S. Department of the Interior.
• Title: Annual Operating Plan for Colorado River Reservoirs 1997.
• USFW Year: 1997.
• USFW - Doc Type: Washington, D.C.
• Copyright Material: NO

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1996 OPERA nONS SUMMARY AND RESERVOIR STATUS

Water year 1996 commenced with above normal hydrologic conditions in the basin. Basin
wide precipitation during 1996 was above average and translated into an above average
snowpack. At the beginning of the I:Unoff season the basin wide snowpack was about
115 percent of average, V8I)'ing between 149 percent of normal in the Upper Colorado River
basin and 65 percent of normal in the San Juan Basin. However, extremely dry conditions in
the late spring reduced the runoff to near normal levels. Annual runoff in the Green River
basin was 103 percent of average, the Gunnison basin was 117 percent of average, the San
Juan basin was 42 percent of average and Lake Powell was 95 percent of average. With this
runoff during 1996 there were some reports of local flooding, but most damage was minimal..

Unregulated inflow into Lake Powell was 13,541 MCM (10.978 MAP) in water year 1996,
approximately 95 percent of average. This inflow resulted in the loss of approximately
1,120 MCM (.908 MAF) of storage in Lake Powell. Approximately 657 MCM (.533 MAP)
of storage was lost in upstream reservoirs, approximately 998 MCM (.809 MAF) of storage
was gained in Lower Basin reservoirs, and the total Colorado storage system lost
approximately 778 MCM (.631 MAF) during water year 1996. It is now estimated that with
average inflow during 1997, the system will be relatively full. During 1996, all deliveries of
water to meet obligations pursuant to "The Law of the River" were maintained. On July 24,
1996, the Regional Directors of the Upper and Lower Colorado regions issued a revised
detennination for 1996 Colorado River water use. acting under authority from the SecretaI)'
of the Interior. This detennination changed the finding of 1996 being a "normal" year to that
of "surplus" as defined in the 1970 Operating Criteria.

Tables l(a) and 1(b) list the expected October 1, 1996 reservoir vacant space, live storage,
water elevation, percent of capacity, change in storage, and change in elevation during water
year 1996.

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