WSP10457

• File Number: 8282.600.10
• Description: Colorado River Operating Annual Reports
• Basin: Colorado Mainstem
• Date: 1/1/1989
• Author: USDOI/BOR
• Title: Operation of the Colorado River Basin 1989 Projected Operations 1990
• Water Supply Pro - Doc Type: Publication

NAVAJO RESERVOIR
(SAN JUAN RIVER)

Water Year 1989

The elevation of Navajo Reservoir at the beginning of the
water year was 6049 feet with 1,215,000 acre-feet of active
storage, or 72 percent of capacity, Navajo Reservoir storage
had been reduced to accommodate the construction of a
coocrete cutoff wall to reduce excessive seepage.
Construction of the cutoff wall was completed in September
1988, It was projected that Navajo Reservoir would reach a
maximum elevation of 6073 feet based on the most probable
1989 runoff,

Navajo Reservoir was gradually drawn down to the elevation
of 6043,6 feet on January 1.1989, and the April through July
runoff forecast at this time was 690,000 acre-feet, or 109
percent of the long-term average. On March I, the April

ACTUAL RELEASES

WY 1989

_cr.
.

.

I

NDJFMAMJJASO

through July forecast had increased to 830,000 acre-feet, then
dropped each month until on June I, it was 500,000 acre-feet
or 79 percent of average, Since Navajo Reservoir was heing
refilled during this time period, releases were kept near a
constant 600 cfs for the entire water year in order to refill the
reservoir.

The actual April through July 1989 runoff volume into Navajo
Reservoir was 424,000 acre-feet, or 67 percent of average. The
total water year 1989 inflow was 730,000 acre-feet which was
76 percent of average, Peak inflow to Navajo reservoir
occurred on April 9, at 3,700 cfs, The reservoir reached a peak
elevation of 6064,8 feet on July 20,1989.

NAVAJO RESERVOIR

Reservoir

Acre-feet

Elevation, feet

Maximum Storage
fnactive Storage
Surface Area, ful1
Reservoir Length, full

1,696,400
660,500

6,085
5,990
15,610 Acres
33 Miles

11