Upper Bear River Basin (13)
March 2001

Snow
Snow water equivalent (SWE), at snow courses in the Bear River above the Idaho State line, is 67 percent of average (78 percent of last year). SWE for the Bear River in Utah is estimated to be 73 percent of average; that is about 81 percent of last year at this time. SWE in the Wyoming portion of the Bear River drainage (Smiths and Thomas Forks) is estimated at 64 percent of average (74 percent of last year at this time.). See the Basin Summary of Snow Course Data at the beginning of this report for more detailed information.

Precipitation
Precipitation for the month of February was 76 percent of average for the 2 reporting stations; this is 54 percent of the previous February. The year- to-date precipitation, for the basin, is 66 percent of average; this is 87 percent of last year's amount.

Reservoir
Woodruff Narrows reservoir is currently storing about 8,000 acre feet. Currently, the reservoir is storing about 16 percent of the volume stored in February of last year. Current storage is about 14 percent of the reservoir capacity.

Streamflow
The following 50 percent chance stream flow yields are for the April through September period. Smiths Fork near Border is estimated to yield 72,000 acre-feet (61 percent of normal), and Thomas Fork drainage near the Idaho-Wyoming state line is estimated to yield 12,000 acre-feet or 33 percent of normal. Bear River near the Utah-Wyoming State Line is expected to yield about 91,000 acre feet (72 percent of average), The Bear River near Woodruff is expected to yield about 103,000 acre-feet (about 67 percent of normal). 



==================================================================================================================================
                                                      UPPER BEAR RIVER BASIN
                                               Streamflow Forecasts - March 1, 2001
==================================================================================================================================
                                              |  <<====== 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)
====================================================================|=======================|=====================================
SMITHS FK nr Border, WY              APR-SEP        51        63    |       72        61    |        82       101            118
                                                                    |                       |
THOMAS FK nr WY-ID State Line (Disc. APR-SEP       7.0       9.7    |     12.0        33    |      14.9        21             36
                                                                    |                       |
Bear R nr UT-WY State Line           APR-SEP        67        81    |       91        72    |       103       123            126
                                                                    |                       |
BEAR R nr Woodruff, UT               APR-SEP        57        81    |      103        67    |       131       185            154
                                                                    |                       |
==================================================================================================================================
                         UPPER BEAR RIVER BASIN                         |                 UPPER BEAR RIVER BASIN
             Reservoir Storage (1000 AF) - End of February              |        Watershed Snowpack Analysis - March 1, 2001
==================================================================================================================================
                                      Usable |  *** Usable Storage ***  |                            Number     This Year as % of
Reservoir                            Capacity|  This      Last          |   Watershed                  of       =================
                                             |  Year      Year     Avg  |                          Data Sites   Last Yr   Average
========================================================================|=========================================================
WOODRUFF NARROWS                        57.3      8.0     50.0      --- |   UPPER BEAR RIVER in Utah    7        81        73
                                                                        |
                                                                        |   SMITHS & THOMAS FORKS       4        74        64
                                                                        |
                                                                        |   BEAR RIVER abv ID line      9        78        67
                                                                        |
                                                                        |   NORTHWEST                  77        65        56
                                                                        |
                                                                        |   NORTHEST                   19        88        71
                                                                        |
                                                                        |   SOUTHEAST                  37        88        80
                                                                        |
                                                                        |   SOUTHWEST                  35        79        71
                                                                        |
==================================================================================================================================
 * 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.
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