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raise, a 300-400 foot new spillway on Cherry Creek Dam with a 9-foot dam raise, a dry dam at the previous Castlewood Canyon Dam Site with no dam raise, a dry dam at West Cherry Creek with a 7.5 foot dam raise, and a dry dam at Scott Road with a 12 foot dam raise. The Corps Study findings, recommendations and public meetings lead a to state level legislative action charging the State of Colorado with an independent peer review of the original 1995 National Weather Service Probable Maximum Precipitation Study. Colorado State General Assembly Resolution 99-023: In response to the Corps recommendations and public meetings, local govemments worked with the Colorado General Assembly to enact Joint Resolution 99-023. Excerpts from Joint Resolution 99-023 mandated state involvement and illustrate the events that led to CWCB involvement. "WHEREAS, the us. Army Corps of Engineers has assumed the Cherry Creek Dam will fail following an extraordmarily improbable chain of events, ... and WHEREAS, this error is fitrther compounded by the erroneous assumption that the topographic effects of the Palmer Divide will increase the rainfall in the Cherry Creek Basin; ... and WHEREAS, any government agency proposal to spend from $50 to $250 million of taxpayer money must be based on data and assumptions that are as accurate as possible... ... ... Be it resolved by the Senate of the Sixty Second General Assembly of the State of Colorado, the House of Representatives concurring herein: That no further funding of the Us. Army Corps of Engineers should be provided for the Cherry Creek Basin Study until the us. Army Corps of Engineers completes an independent peer review of the National Weather Service data in order to determine the appropriate design floodfor the Cherry Creek Basin. Be itfurther resolved: that copies of this joint resolution be sent to the President of the United States, the President of the United States Senate, the Speaker of the us. House of Representa tives, each member of Colorado 's Congressional delegation, the Governor of the State of Colorado, the Commander of the us. Army Corps of Engineers, and the Colorado Water Conservation Board. " The State of Colorado's Independent Review of the National Weather Service's 1995 Probable Maximum Precipitation Study: Colorado Joint Resolution 99-023 required the CWCB to conduct an independent peer review of the National Weather Service's Probable Maximum Precipitation Study used by the Corps. The CWCB released a Request for Qualifications in 1999. Dr. Ed Tomlinson of Applied Weather Associates (A W A) Monument, Colorado was selected in 2000 to develop a study team, complete the independent review of the NWS Study, and conduct a site-specific PMP Study for the Cherry Creek Basin. Many professionals participated in technical tasks for the study and John Henz of HDR Engineering conducted analyses of Colorado severe storms. The CWCB funded half of the Study costs and the communities of Greenwood Village, Aurora, Englewood, and Douglas County were co-sponsors. Representatives from those communities were active participants at project meetings. A Technical Review Panel (TRP) of Experts was developed to comment on study findings and methodologies. The TRP was (Lou Schreiner US Bureau of Reclamation) (Nolan Doesken Assistant State Climatologist) and (Gary Lewis Parsons Engineering). The TRP members provided insight throughout the study and written comments on: Interim Report # 1, Interim report # 2, the Draft Final Report, and attended the Final Project Meeting and provided final oral comments. The A W A findings and recommendations are presented in a report entitled "Technical Review for r.t.t! St.ln" /,.6)"ml ~'U"flJ f", Si~1t1 pI hiM I.. /9iJ Using standard PMP methodologies the A W A team took the storm patterns of the ten extreme Colorado Storms, rotated and critically centered the storms in the Cherry Creek basin in order to come up with the maximum rainfall amounts or worst-case rainfall amounts in making the A W A PMP determinations. 2