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Page | 8 Georgetown Lake Dam Outlet Modification Project – Georgetown Colorado The ogee spillway section of the dam is 100 feet long and 13 feet high. The crest of the spillway is at an elevation of 8,447.85 ft per the NAVD 8 datum. The spillway apron is at an elevation of 8,434.85 feet. The maximum spillway base width at the apron elevation is roughly 19.5 feet. The top of the dam is at an elevation of 8,457.85 ft. The existing outlet works (the issue herein), consists of a 48 inch square ARMCO slide gate on the face of the spillway. A 48 inch square concrete conduit passes through the spillway at an elevation of 8,434.95 ft. The conduit outlet is contoured to complement the ogee shape on the downstream side of the spillway. The gate is operated either manually or with a recently installed solar powered electric actuator, controlled via a SCADA system. IX. P ROJECT The project consists of engineering and constructing a modification to the Georgetown Lake Dam outlet works so that 500 c.f.s can be released when the Lake is full, in order to implement the Court’s Final Orders in Case No. 2008CW266. Currently the lake’s outlet structure can only release about 260 c.f.s. In 2007, AECOM/TCB evaluated several alternatives to increase the lake’s total release capacity to 500 c.f.s (“Outlet Study”), refer to Exhibit #H. The 2007 Outlet Study evaluated several alternatives for increasing the outlet capacity of Georgetown Lake. in order to allow for the controlled release of up to 500 c.f.s of stored water. The Outlet Study, as presented in Exhibit #H was not prepared by or under the direction or supervision of either F&D International LLC nor Todd E. Ficken, PE The Outlet Study considered three alternative designs. The surrounding terrain is very challenging, thus due to the terrain and the constraint of having to work within the existing dam structure, there were only a limited number of realistic alternatives, specifically: