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<br />2) <br /> <br />3) <br /> <br />Definition and adjustments for orographic effects regarding storm positioning: <br />· The present definition of orographic effect does not consider an adjustment for the <br />topographic features that may lie within the basin or its borders. <br />· By definition, the PMP storm center must be positioned at the point where the <br />maximum rainfall runoff will occur and does not consider historical storm tracks and <br />patterns for the region in the analyses. <br />Depth and duration relationships used in the Site-Specific study are not correlated with <br />Colorado's historical events; however, HMR 55A guidelines were considered. <br />There is much concern regarding the antecedent precipitation conditions that were <br />assumed before the "PMP Event" occurs. <br />The Cherry Creek basin has a true north-south orientation. Recorded major storm events <br />in Colorado track in a west east or an east-west direction. This fact poses a question <br />regarding the positioning of the PMP storm within the Cherry Creek basin. <br />The fact that the NWS is the keeper of the "state of the practice for PMP" is an accepted <br />one; however, much "Best Professional Judgement" is often used in a PMP study. It is <br />in the client's best interest to obtain a consensus regarding these "best professional <br />judgements" decisions by an independent expert. <br />Many of the answers to the questions in the "Topics for technical meeting concerning the <br />Site Specific Probable maximum Precipitation (PMP) for the Cherry Creek Drainage in <br />Colorado" received a no consensus is reached by the group see attached draft dated July <br />21,1999. Note: A "no consensus" answers was provided when as few as one opposing <br />response was received on a topic. <br /> <br />e <br /> <br />4) <br /> <br />5) <br /> <br />6) <br /> <br />7) <br /> <br />ACTIONS UNDER CONSIDERATION <br /> <br />e <br /> <br />I) <br /> <br />The local professional interests who were present at the July 21 and 22, 1999 meetings <br />are requesting a formal response from the Corps regarding PMP study findings that will <br />be reviewed by the NWS, and what the schedule is for the performance of these tasks. <br />The CWCB is addressing this request with a formal letter to the Corps. <br />The CWCB staff will meet with the Corps of Engineers on August 28, 1999 to address <br />concerns and issues in item number one and other concerns and issues that are presented <br />to the Board by Colorado interests. <br />Determine a procedure for conducting independent technical review of the NWS July 13, <br />1995 Cherry Creek Site Specific Study that will be beneficial to the Corps, the NWS, and <br />Colorado interests. <br />Provide the concerned citizens and non-federal interests with a frequency analyses that <br />will state the re-occurrence level for the flood control and other storage pools in the <br />reservOIr. <br />Should a risk base analyses rather than a PMF analyses are considered for the darn safety <br />study? <br />Request that the Corps assist with technical and financial resources in the preparation of a <br />"Scopes of Work" and contracting of a technical review study for the Cherry Creek <br />Drainage Basin. <br />Make a request to the Corps to have them acknowledge the Colorado's concerns as <br />expressed in the following recent study act\vities: <br />· Message to the Corps in the Tom Tancredo News Release, dated July 22,1999; <br /> <br />e <br /> <br />2) <br /> <br />3) <br /> <br />4) <br /> <br />5) <br /> <br />6) <br /> <br />7) <br /> <br />4 <br />