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. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - PMF Determination for Amistad and Falcon Dams Required data for performing the Probable Maximum Flood (PMF) analysis will be collected, This will include Probable Maximum Precipitation (PMP) studies from U,S, and Mexico weather service agencies; large-scale topographic mapping (e,g" USGS 1:250,000 scale maps) for the watersheds tributary to each dam; reservoir stage-volume- discharge data for each facility; USGS 7-112 minute map topographic data for the floodplain between the two reservoirs; and operating rules for the upstream reservoirs (e,g" Elephant Butte, Caballo) during PMF-type events, Based on the available data, a specific work plan for computing the PMF will be developed and submitted to mwc for review and approval. PMP rainfall depths on the U.S, side will be taken from National Weather Service publications such as HMR 55, PMP rainfall depths on the Mexico side will be taken from published reports if possible, or extrapolated from applicable information for the U,S, portions of the watersheds, Scenarios for PMP storm pattern, location, size and movement will be derived from NOAA and NWS publications, A simple watershed model for the tributary area to each reservoir will be developed using the HEC-I model. Models will be used to simulate the various PMP scenarios and compute alternative PMF hydrographs, The worst-case condition will be selected as the PMF, Routed PMF hydrographs at each dam site will be provided in FLOW A V input format in Excel spreadsheets, Draft and final reports will be prepared describing the analysis and results of the PMF determination study.