Wind River Basin (3)
February 2000

Snow
The Wind River basin has well below average snow water equivalent (SWE) for this time of the year. The Wind River above Dubois is 74 percent of average (64 percent of last year). The Little Wind is 54 percent of average water content (53 percent of last year), and the Popo Agie drainage is about 60 percent of average (68 percent of last year). The Wind River basin, above Boysen Reservoir, SWE is about 67 percent of average (about 65 percent of last year). See the Basin Summary of Snow Course Data at the front of this report for details.

Precipitation
January precipitation in the basin varied from 4 to 164 percent of average. January precipitation for the basin was about 117 percent of average for the 8 reporting stations; that is about 111 percent of last year's amount. Water year-to-date precipitation is 66 percent of normal. The current water-year-to-date average is about 60 percent of last year at this time. Year to date figures range from 15 to 79 percent of average.

Reservoirs
Current storage varies from 91 to 136 percent of average. Bull Lake is currently storing about 95,000 acre feet (63 percent of capacity) -- normally the reservoir is at 57 percent of capacity at this time of the year. Boysen Reservoir is storing about 89 percent of capacity 531,300 acre feet) -- normally the reservoir is at 97 percent of capacity at this time of the year. Pilot Butte is storing 71 percent of capacity (22,500 acre feet) -- normally the reservoir is at 52 percent of capacity at this time of the year.

Streamflow
Water supply is estimated to be below normal this year. The following values reflect the 50 percent chance yields for the April through September runoff period. The Wind River above Bull Lake Creek is expected to yield 450,000 acre feet (84 percent of average). Wind River at Riverton will yield about 510,000 acre feet (79 percent of average). Boysen Reservoir inflow will yield about 555,000 acre feet (59 percent of normal). Bull Lake Creek near Lenore is expected to yield about 148,000 acre feet (81 percent of average). Little Popo Agie River near Lander is expected to yield about 36,000 acre feet (69 percent of average). South Fork of Little Wind near Fort Washakie will yield about 56,000 acre feet (69 percent of average). Little Wind River near Riverton will yield about 180,000 acre feet (56 percent of average). 

==================================================================================================================================
                                                         WIND RIVER BASIN
                                               Streamflow Forecasts - February 1, 2000
==================================================================================================================================
                                              |  <<====== Drier ======  Future Conditions  =======  Wetter =====>>  |             
                                              |                                                                     |
  Forecast Point                     Forecast |  ==================== Chance Of Exceeding * ======================  |
                                      Period  |    90%       70%    |  50% (Most Probable)  |      30%       10%    |  30-Yr Avg.
                                              | (1000AF)  (1000AF)  |   (1000AF)  (% AVG.)  |    (1000AF)  (1000AF) |    (1000AF)
====================================================================|=======================|=====================================
WIND RIVER abv Bull Lake Cr (2)      APR-SEP       330       401    |      450        84    |       499       570            538
                                                                    |                       |
WIND RIVER at Riverton (2)           APR-SEP       274       415    |      510        79    |       605       746            648
                                                                    |                       |
BOYSEN RESERVOIR Inflow (2)          APR-SEP       233       425    |      555        69    |       685       877            809
                                                                    |                       |
BULL LAKE CR near Lenore (2)         APR-SEP       107       131    |      148        81    |       165       189            183
                                                                    |                       |
LT POPO AGIE RIVER nr Lander         APR-SEP       5.7        24    |       36        69    |        48        66             52
                                                                    |                       |
SF LT WIND nr Fort Washakie          APR-SEP        27        44    |       56        69    |        67        85             81
                                                                    |                       |
LT WIND RIVER nr Riverton            APR-SEP        31       120    |      180        56    |       240       329            324
                                                                    |                       |
==================================================================================================================================
                            WIND RIVER BASIN                            |                    WIND RIVER BASIN
             Reservoir Storage (1000 AF) - End of January               |        Watershed Snowpack Analysis - February 1, 2000
==================================================================================================================================
                                      Usable |  *** Usable Storage ***  |                            Number     This Year as % of
Reservoir                            Capacity|  This      Last          |   Watershed                  of       =================
                                             |  Year      Year     Avg  |                          Data Sites   Last Yr   Average
========================================================================|=========================================================
BULL LAKE                              151.8     95.0     97.8     86.6 |   WIND RIVER above Dubios     7        64        74
                                                                        |
BOYSEN                                 596.0    531.3    569.3    580.7 |   LITTLE WIND                 2        53        54
                                                                        |
PILOT BUTTE                             31.6     22.5     22.3     16.5 |   POPO AGIE                   6        68        60
                                                                        |
                                                                        |   WIND above Boysen Resv     14        65        67
                                                                        |
==================================================================================================================================
 * 90%, 70%, 30%, and 10% chances of exceeding are the probabilities that the actual volume will exceed the volumes in the table.

The average is computed for the 1961-1990 base period.

(1) - The values listed under the 10% and 90% Chance of Exceeding are actually 5% and 95% exceedance levels.                  
(2) - The value is natural volume - actual volume may be affected by upstream water management.


	BIGHORN RIVER BASIN as of February 1, 2000
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