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COAST FORK WILLAMETTE--COTTAGE GROVE DAM
   State:  Oregon    County:  LANE
   Latitude:  43 43' 12" North    Longitude:  123 3' 0" West
   Elevation:  800 feet
   Supporting WFO:  Portland    
   Inflow Data  

Forecasts are calculated from a forecast time series that approximates flow at a 6 hour time step interval. Observed instantaneous peaks can be higher than model forecast peaks.

COAST FORK WILLAMETTE--COTTAGE GROVE DAM   (COTO3)
Forecasts for Water Year
2026
Ensemble Date: 2026-05-07
Forecast Period: May 7 to September 1
Exceedence
Probability
Inflow
CFS
Probable
Date of Peak
95 % 93 2026-05-07
90 % 93 2026-05-07
70 % 123 2026-05-22
50 % 133 2026-05-29
30 % 184 2026-06-07
10 % 305 2026-06-29
05 % 717 2026-07-14

Peakflow exceedence plot for COTO3

 Click to download runoff traces used in forecast.  Click for comma delimited data used in plot.csv icon