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<br />'. <br /> <br />.. A review and acceptance of procedures for determination of storm depths, durations, rainfall areas, <br />and storm center locations is needed <br /> <br />What is a reasonable PMP event? Elements to be consideredfor a PMP event are: <br /> <br />· Storm location, positioning, and movement <br /> <br />· Areal extent (size), temporal distribution, and total duration of storm event <br /> <br />· Antecedent moisture condition for storm #1 and storm #2 (Note: assumptions for storm #1 and storm <br />#2 are that they are 24 hours apart and one has a greater precipitation total) <br /> <br />· Soil infiltration values and classifications <br /> <br />· Rainfall north of Palmer Divide vs. south of Palmer Divide due to moisture sources and topographic <br />barriers <br /> <br />· Climate changes, global warming, major shifts in weather patterns <br /> <br />· What is the probability or frequency estimate ofthe current PMP/PMF value? <br /> <br />· Have local topographic features and orographic effects of mountains been considered in the present <br />PMP analysis? <br /> <br />· How did the National Weather Service analyze and maximize the PMP event? <br /> <br />Characteristics/Concerns about the CherTY Creek dam: <br /> <br />· Failure ofthe dam embankment causes inundation of downstream neighborhoods. Why not simply <br />lower the level of flood protection by constructing a larger spillway similar to Chatfield dam? <br /> <br />· The wind analysis and wave-run up calculations appear to be questionable. What is the direction, <br />average speed, and maximum speed of the wind? What is the maximum wave height? <br /> <br />· What is the maximum overtopping depth of the existing embankment (based on Corps' PMF value) <br />and how will the overtopping occur? <br /> <br />· If overtopping of the dam occurs, what is the erosion rate and estimated time to failure? Can the <br />downstream side of the embankment be protected to act as a spillway? <br /> <br />· What is the flood protection (in terms of frequency) for downstream properties based on current <br />hydrology? <br /> <br />· What is the purpose of the Dam and Reservoir Safety manual (O&M manual?)? <br /> <br />3 <br />