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Dan Mathews -2- November 5, 2007 9. DRMS - In the SEDCAD demonstration for the Powder Magazine Ephemeral Channels, the CRDA-2 East Drainage (6.96 acres) and the Roadside North, West Diversion (3.33 acres) were not included in the Structure Networking. Also, there were no Muskingum Routing details provided in the demonstration. All of the cumulative flows were accounted for in the utility runs for the channel designs and the cumulative design discharges appeared correct except for the #3 Watershed. Based on the information provided, it appears that the design discharge for #3 watershed utility runs should be 15.27 cfs as opposed to 15.77 cfs. This is probably insignificant since conservative designs are proposed using a 1.00 ft. freeboard depth. However, it is necessary to show accurate structure networking. Please revise the SEDCAD demonstration to include accurate and complete structure networking and if appropriate routing details for each subwatershed/structure. SCC -The reason the SEDCAD demonstration was not completely networked is because the program has no way to account for base or other flows. Flow from CRDA-2 East Drainage (6.96 cfs) and flow from Roadside North West Diversion (3.33cfs) were added to the flow network shown on page MISC-24. DRMS is correct the design discharge for #3 watershed should be 15.27 cfs as opposed to 15.77 cfs. Accurate structure networking is presented on page MISC-24. Page MISC-29 was amended to show Muskingum Routing details. The time of concentration was changed to 0.1 hours for ali watersheds. The flows for MISC-35 & 36 were changed to 15.27 cfs which resulted in little change in the design. Enclosed are amended pages MISC-24, 29, 35 & 36. 10. Item Resolved. Sincerely, ~`~~ Tonya K, Hammond Owner's Representative Enclosures: Appendices: Revised pages MISC-24, 29, 35 & 36 cc: DRMS Denver, Mesa County Clerk, BLM, SCC File