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Wyoming Basin Outlook Report for
UPPER GREEN RIVER BASIN as of March 1, 2012

Snow SWE in the Green River Basin above Warren Bridge is about 91% of average. SWE for the West Side of Upper Green River Basin is about 89% of average. Newfork River Basin SWE is now about 99% of average. Big Sandy-Eden Valley Basin is 85% of average. SWE in the Green River Basin above Fontenelle Reservoir is about 91% of average. For more information see Basin Summary of Snow Course Data at the beginning of this report. Precipitation The 11 reporting precipitation sites in the basin were 104% of average last month (121% of last year). Last month s precipitation varied from 57-127% of average. Water year-to-date precipitation is about 99% of average (89% of last year). Year to date percentage of average ranges from 82-115% for the reporting stations. Reservoir Storage in Big Sandy Reservoir is 23,400 ac-ft or 61% of capacity. This is 123% of average. Fontenelle Reservoir is 125,300 ac-ft or 36% of capacity; 80% of average. This is 85% of average for the Upper Green River basin. Detailed reservoir data is shown on the following page and on the reservoir storage summary at the beginning of this report. Streamflow The 50% exceedance forecasts for the April through July runoff period in the Upper Green River Basin are forecast to be below average. The yield on the Green River at Warren Bridge is 250,000 ac-ft (94% of average). Pine Creek above Fremont Lake is 100,000 ac-ft (96% of average). New Fork River near Big Piney is 365,000 ac-ft (92% of average). Fontenelle Reservoir Inflow is estimated to be 730,000 ac-ft (85% of average), and Big Sandy near Farson is expected to be around 52,000 ac-ft (90% of average). See the following table for more detailed information on projected runoff.

Streamflow Forecasts

Streamflow Forecasts - March 1, 2012

 <==== Drier === Future Conditions === Wetter ====> 
Forecast Pt============ Chance of Exceeding * =========== 
   Forecast90%70%50% (Most Prob)30%10%30 Yr Avg
   Period(1000AF)(1000AF)(1000AF)(% AVG.)(1000AF)(1000AF)(1000AF)

Green R at Warren Bridge
APR-JUL 199       230       250       94       270       305       265      
Pine Ck ab Fremont Lake
APR-JUL 84       93       100       96       107       117       104      
New Fork R nr Big Piney
APR-JUL 265       320       365       92       410       485       395      
Fontenelle Reservoir Inflow (2)
APR-JUL 480       620       730       85       845       1040       860      
Big Sandy R nr Farson
APR-JUL 37       46       52       90       59       70       58      

    * 90%, 70%, 30%, and 10% chances of exceeding are the probabilities that the
       actual flow will exceed the volumes in the table.

    (1) - The values listed under the 10% and 90% Change of Exceeding are
            actually 5% and 95% exceedance levels.
    (2) - The value is natural flow - actual flow may be affected by upstream
            water management.

Reservoir Storage

Reservoir Storage (1000AF) End of February

 Usable************* Usable Storage *************
Reservoir Capacity This Year Last Year Average

BIG SANDY 38.3      23.4         18.5          19.1        
FONTENELLE 344.8      125.3         157.6          156.1        

Watershed Snowpack Analysis

Watershed Snowpack Analysis - March 1, 2012

 Number ofThis Year as Percent of
Watershed Data Sites Last Year Normal

GREEN above Warren Bridge 5               85               91              
UPPER GREEN (West Side) 7               77               89              
NEWFORK RIVER 3               103               99              
BIG SANDY/EDEN VALLEY 2               93               85              
GREEN above Fontenelle 14               83               91              

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or Write:
D. Lee Hackleman, Water Supply Specialist
Natural Resources Conservation Service
100 East B Street
Casper, WY 82601
(307) 261-6481

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