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I I I I I I I I I I I I I I I I I I I Proposed golf course construction will alter floodplain characteristics appreciably throughout the site, but upstream of 1-25 within the City of Westminster, the 100-year water surface will remain the same as for existing conditions. Because no habitable structures will exist in the floodplain on the course, the 100-year flood way and 100- year floodplain will have the same delineation for both FEMA and UDFCD flows. Abutting property owners affected by the changes on the golf course area have agreed to remove their property from the proposed floodplain. Riprap was sized for areas on Big Dry Creek that will need stream stabilization, high velocity protection, and storm sewer outfall protection. Typical sections were established after working closely with the wetlands and landscape consultant and golf course architect. The total of the channel protection measures is estimated at $312,270. As a rough estimate, $21,530 was used for a construction estimate for each of the four creek crossings, plus $3,700 for erosion protection at each site. Therefore, the sum of capital construction costs associated with Big Dry Creek is $413,190 ($516,600 with 25 percent contingency for estimating construction contingency (10 percent) and engineering design fees and construction services (15 percent)). The stabilization plan proposed herein is a reasonable balance between capital construction costs, ongoing maintenance costs, and golf course landscape aesthetics. Future maintenance will be necessary. However, the effort should be modest and the stream should be stabilized and controlled to prevent drastic migration into and destruction of the golf course fairways as well as unsafe streambanks. If stream banks are left unprotected and unstabilized, the City would be leaving itself open to incurring substantial ongoing operating and maintenance expenses to deal with this somewhat unpredictable situation. Experience involving the Cherry Hills Country Club is a graphic example of the need to design and construct these protection measures. Note, however, that this is not a guarantee as this project will compete with other maintenance needs. Finally, improvements to the 1-25 bridge were suggested. The UDFCD's 100-year water surface upstream of 1-25 can be lowered about 5.9 feet by excavating the invert of the bridge and constructing a 3.1-foot drop structure upstream. 1-3