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. flows would be routing effects, not detention effects. This would be in agreement with our Rules and Regulations for designation of floodplain information. Please confirm whether our assumption is correct or not. Corps Response #8. The five reservoirs included in the SWMM were assumed filled to the spillway crest so that the only effects in reducing flows was from surcharge routing and not detention. CWCB Comment #9. How sensitive is the selection of snowmelt skews on the final results? Mr. Jarrett found a regional rainfall skew of +0.22, a regional snowmelt skew of +0.10, and a combined regional skew of +0.18 for the South Platte River Basin. You used a skew of zero. If we accept Mr. Jarrett's Mean Logarithm and standard deviations, why not his regional skew also? We would like to be involved in the selection of one of those skews or some other appropriate skew and in the use of the resultant gage analysis in calibrating the SWMM analysis. The Jarrett/Costa information is not necessarily the only data source for this process. Corps Response #9. Our revised analysis used the regional skews derived by Jarrett which were weighted with the computed station skews in accordance with guidelines in WRC Bulletin 17B. (Note! The regional snowmelt skew used was -0.10). For the mixed population analysis at Lawson, the regional skew was adopted without weighting in order to be conservative. CWCB Comment #10. We have a final comment. The next draft should include a bibliography, a table of contents, and a comparison with previous studies (specifically previous studies that have been approved and designated by the Colorado Water Conservation Board) . Corps Response #10. The requested information has been added to the revised report. 5