Regional Event Briefing Jim Croston P.E., Scott Henderson P.E. John Daylor P.E. Hydrology and Hydraulics Branch September 28, 2010 US Army Corps of Engineers BUILDING STRONG® Regional Event Briefing: Reservoir Infow & Elevation Forecasting John Daylor P.E. Hydrology and Hydraulics Branch September 28, 2010 US Army Corps of Engineers BUILDING STRONG® Reservoir Inflow & Elevation Forecasting: What is it? Obtain estimated stream flow into reservoir to anticipate effects and actions for reservoir managg(g,p,ement (timing, peak, and volume) . Why? Enhance decisions & operations of reservoir & syyppstem for authorized purposes. BUILDING STRONG® Variability of Reservoir Inflow and Elevation Forecasting ¾ NonNon--ExactExact Science of Hydrology ¾ Antecedence, Moisture Conditions ¾ Seasonal Effects ¾ Storm Size & Pattern & Duration ¾ Field Data Reliability ¾ Initial Conditions of Reservoir ¾ Basin System Conditions, Fullness BUILDING STRONG® Upper Verdigris River Basin Toronto Lake Fall River Lake Big Hill Lake Elk City Lake Oologah Lake BUILDING STRONG® Upper Verdigris River Basin Regulation Point Toronto Lake Coyville Fall River Altoona Fall River Lake Fredonia Elk City Lake Big Hill Lake Cherryvale Independence Coffeyville Lenapah Oologah Lake BUILDING STRONG® Toronto Lake & Dam: Upper Verdigris River Basin BUILDING STRONG® 24-Hour Precipitation from Digital Radar 7 AM 8 June – 7 AM 9 June 2010 7.72’’ 7827.82’’ Toronto Dam 3.10’’ BUILDING STRONG® Verdigris River @ Virgil, KS Observed & Forecasted River Flow BUILDING STRONG® Toronto Lake Inflow & Elevation Forecast Surcharge Zone Top Flood Storage Zone Elev 931.0 @ Elev 926.0 Flood Storage Zone 73.2% F.S. Normal Lake Elev 901.5 Forecasted Inflow Release Plan BUILDING STRONG® Reservoir Inflow & Elevation Forecasting Questions? BUILDING STRONG®.