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 100,000 acre-feet (87 percent of normal).
Water users on the Middle Fork near Barnum should have a yield near
9,000 acre-feet (46 percent of normal). The North Fork of the Powder
near Hazelton should yield about 6,900 acre-feet (68 percent of
normal). The estimated yield for Clear Creek near Buffalo is 27,000
acre-feet (69 percent of average). Rock Creek near Buffalo will
yield about 29,500 acre-feet (81 percent of normal), and Piney Creek
at Kearny should yield about 42,500 acre-feet (83 percent of
average).
================================================================================================================================== POWDER & TONGUE RIVER BASINS Streamflow Forecasts - April 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) ====================================================================|=======================|===================================== TONGUE RIVER nr Dayton (2) APR-SEP 72 89 | 100 87 | 111 128 115 | | MIDDLE FORK POWDER nr Barnum APR-SEP 1.9 6.1 | 9.0 46 | 11.9 16.1 19.7 | | NORTH FORK POWDER nr Hazelton APR-SEP 4.3 5.8 | 6.9 68 | 8.0 9.5 10.1 | | CLEAR CREEK nr Buffalo APR-SEP 18.3 24 | 27 69 | 31 36 39 | | ROCK CREEK nr Buffalo APR-SEP 12.7 16.7 | 19.5 81 | 22 26 24 | | PINEY CREEK at Kearny APR-SEP 16.8 32 | 43 83 | 53 68 51 | | ================================================================================================================================== POWDER & TONGUE RIVER BASINS | POWDER & TONGUE RIVER BASINS Reservoir Storage (1000 AF) - End of March | Watershed Snowpack Analysis - April 1, 2000 ================================================================================================================================== Usable | *** Usable Storage *** | Number This Year as % of Reservoir Capacity| This Last | Watershed of ================= | Year Year Avg | Data Sites Last Yr Average ========================================================================|========================================================= TONGUE RIVER 68.0 36.9 12.3 36.1 | UPPER TONGUE RIVER 8 111 90 | | GOOSE CREEK 2 109 83 | | CLEAR CREEK 4 106 85 | | CRAZY WOMAN CREEK 3 98 81 | | UPPER POWDER RIVER 4 100 85 | | POWDER RIVER in WY 8 103 85 | ================================================================================================================================== * 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.