Streamflow
The 50 percent chance May through September runoff is anticipated to
be below normal. The Boysen Reservoir inflow is forecast to yield
320,000 acre feet (42 percent of average); the Greybull River nr
Meeteese should yield 80,000 acre feet (41 percent of average); Shell
Creek near Shell should yield 52,000 acre feet (72 percent of average)
and the Bighorn River at Kane should yield 445,000 acre feet (43
percent of average).
================================================================================================================================== BIGHORN RIVER BASIN Streamflow Forecasts - May 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) ====================================================================|=======================|===================================== BOYSEN RESERVOIR Inflow (2) MAY-SEP 211 276 | 320 42 | 425 579 758 | | GREYBULL RIVER nr Meeteetse MAY-SEP 64 73 | 80 41 | 96 120 195 | | SHELL CREEK nr Shell MAY-SEP 42 48 | 52 72 | 56 63 72 | | BIGHORN RIVER at Kane (2) MAY-SEP 283 379 | 445 43 | 598 822 1039 | | ================================================================================================================================== BIGHORN RIVER BASIN | BIGHORN RIVER BASIN Reservoir Storage (1000 AF) - End of April | Watershed Snowpack Analysis - May 1, 2001 ================================================================================================================================== Usable | *** Usable Storage *** | Number This Year as % of Reservoir Capacity| This Last | Watershed of ================= | Year Year Avg | Data Sites Last Yr Average ========================================================================|========================================================= BOYSEN 596.0 437.3 501.4 502.6 | NOWOOD RIVER 5 97 59 | BIGHORN LAKE 1356.0 841.2 877.6 789.2 | GREYBULL RIVER 2 60 31 | | SHELL CREEK 4 78 70 | | BIGHORN (Boysen-Bighorn) 11 82 61 | ================================================================================================================================== * 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.