Upper Bear River Basin
March 1997

Snow Snow water equivalent (SWE) at data sites in the Upper Bear River above the Idaho State Line is 90 percent above average (the same as last month). The Upper Bear River in Utah measured about 79 percent more SWE than average; that is about 24 percent more than last year at this time. SWE In the Wyoming portion of the Bear River drainage (Smiths and Thomas Forks) is estimated to be about 87 percent of average (about 31 percent more than last year). 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 about 66 percent below average for the two reporting stations; this is about 45 percent less than February of last year. The year-to-date precipitation figure for the basin is 144 percent of average; this is about 25 percent more than last year.

Reservoir
Woodruff Narrows Reservoir presently contains about 30,200 acre feet of water; that is compared to 45,000 acre feet at this time last year.

Streamflow
The 50 percent chance April - September stream flow yields are expected to be much above average in the Bear River drainage. The Bear River at the Utah State Line is expected to yield 186,000 acre feet; that is about 48 percent more than average. The Thomas Fork drainage is estimated to yield 68,000 acre feet or 89 percent more than normal for the April -- September period. The 50 percent chance yield for Smiths Fork near Border is about 200,000 acre feet (69 percent more than normal) for the April - September period. The Bear River near Woodruff is expected to yield about 225,000 acre feet, about 51 percent more than normal for the April-July period. 

==================================================================================================================================
                                                      UPPER BEAR RIVER BASIN
                                               Streamflow Forecasts - March 1, 1997
==================================================================================================================================
                                              |  <<====== 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 FORK nr Border, WY            APR-SEP       164       185    |      200       170    |       215       236            118
                                                                    |                       |
THOMAS FK nr WY-ID State Line        APR-SEP        37        53    |       68       189    |        87       124             36
                                                                    |                       |
BEAR R nr UT-WY State Line           APR-SEP       135       163    |      186       148    |       212       257            126
                                                                    |                       |
BEAR R nr Woodruff (2)               APR-JUL       119       182    |      225       151    |       268       331            149
                                                                    |                       |
==================================================================================================================================
                         UPPER BEAR RIVER BASIN                         |                 UPPER BEAR RIVER BASIN
             Reservoir Storage (1000 AF) - End of February              |        Watershed Snowpack Analysis - March 1, 1997
==================================================================================================================================
                                      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     30.2     45.0      --- |   UPPER BEAR RIVER in Utah    5       112       150
                                                                        |
                                                                        |   SMITHS & THOMAS FORKS       4       122       152
                                                                        |
                                                                        |   BEAR RIVER abv ID line     11       120       155
                                                                        |
==================================================================================================================================
 * 90%, 70%, 30%, and 10% chances of exceeding are the probabilities that the actual flow 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 flow - actual flow may be affected by upstream water management.
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