Streamflow
The following runoff values are for the 50 percent probability during the April through September forecast
period. The estimated yield for Tongue River near Dayton is 59,000-acre feet (54 percent of normal). Middle
Fork of the Powder River near Barnum is estimated to yield 8,700-acre feet (47 percent of average). The
North Fork of the Powder near Hazelton should yield about 5,700 acre-feet (55 percent of normal). The
estimated yield for Clear Creek near Buffalo is 21,000 acre-feet (54 percent of average). Rock Creek near
Buffalo will yield about 12,500 acre-feet (52 percent of normal), and Piney Creek at Kearny should yield about
25,000 acre-feet (48 percent of average).
================================================================================================================================== POWDER & TONGUE RIVER BASINS Streamflow Forecasts - February 1, 2002 ================================================================================================================================== | <<====== 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) ====================================================================|=======================|===================================== TONGUE RIVER nr Dayton (2) APR-SEP 43 52 | 59 54 | 71 89 109 | | MIDDLE FORK POWDER nr Barnum APR-SEP 5.1 7.2 | 8.7 47 | 11.8 16.3 18.7 | | NORTH FORK POWDER nr Hazelton APR-SEP 4.2 5.1 | 5.7 55 | 6.8 8.3 10.4 | | CLEAR CREEK nr Buffalo APR-SEP 16.7 19.3 | 21 54 | 24 29 39 | | ROCK CREEK nr Buffalo APR-SEP 9.8 11.4 | 12.5 52 | 14.6 17.8 24 | | PINEY CREEK at Kearny APR-SEP 12.3 19.9 | 25 48 | 36 51 52 | | ================================================================================================================================== POWDER & TONGUE RIVER BASINS | POWDER & TONGUE RIVER BASINS Reservoir Storage (1000 AF) - End of January | Watershed Snowpack Analysis - February 1, 2002 ================================================================================================================================== Usable | *** Usable Storage *** | Number This Year as % of Reservoir Capacity| This Last | Watershed of ================= | Year Year Avg | Data Sites Last Yr Average ========================================================================|========================================================= TONGUE RIVER 79.1 21.8 34.0 22.7 | UPPER TONGUE RIVER 9 111 72 | | GOOSE CREEK 2 108 71 | | CLEAR CREEK 4 126 73 | | CRAZY WOMAN CREEK 3 168 76 | | UPPER POWDER RIVER 4 121 72 | | POWDER RIVER in WY 8 123 73 | ================================================================================================================================== * 90%, 70%, 30%, and 10% chances of exceeding are the probabilities that the actual volume will exceed the volumes in the table. (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.