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-2- November 1, 2011 <br />approximately 40 feet terminated at a concrete bulkhead wall which had two, 30 -inch- <br />diameter intake pipes through the bottom of the wall. The rockcut tunnel made a gradual <br />transition from the horseshoe tunnel termination to an open chamber approximately 7 feet <br />wide by 10 feet high. <br />The 30- inch - diameter pipes were approximately 15 feet in length and supplied the two, 30- <br />inch- diameter gate valves located in the vertical rockcut shaft and downstream tunnel. The <br />valves discharged directly into the downstream rockcut tunnel. <br />The downstream rockcut tunnel was generally 5 feet wide by 7 feet high but had four <br />locations where the tunnel width narrowed to 42 inches. The alignment was not straight but <br />veered right and left at approximate 15 to 20 degree angles about every 40 feet. The <br />daylight discharge to the stream channel was visible at approximately 40 feet from the exit <br />point. <br />GPS survey points were taken at the tunnel intake, the center of the vertical valve shaft, and <br />at the daylight discharge of the downstream tunnel. All other measurements are <br />approximate. <br />Section 3 Outlet Inspection <br />3.1 Intake Structure <br />The exterior of the intake structure was completely surrounded by silt and located in a <br />depression in the reservoir bottom. The top of the deposited silt is approximately 7.6 feet <br />above the structure control section. The center section of the top trashrack was removed <br />and laying on top of the silt deposits, approximately 50 feet to the northeast of the intake <br />structure. There is a low -level intake opening with trashrack on the upstream side of the <br />intake structure. The opening extends from the floor of the intake structure upward <br />approximately 2.5 feet and extends across the front of the structure. The opening has a <br />trashrack across it and is completely silted in with no flow coming through the opening. <br />Intake structure concrete was generally in good condition, having no apparent cracks, <br />displacement, or spalling. Chipped concrete was noted on the right (west) side of the <br />horseshoe shaped concrete intake tunnel. The floor of the intake structure was completely <br />covered with silt and silt -laden inflow and was not visible at the time of inspection. <br />Inspection of the floor was completed using a wooden dowel to probe and "feel" the floor. <br />This inspection procedure found no cracks or holes in the intake structure floor. Based on <br />the inspection, the intake is considered serviceable and sufficient for consideration of reuse <br />in rehabilitation alternatives development. <br />The trashrack was found to be in very poor overall condition displaying advanced corrosion <br />on all surfaces that has reduced steel framing member cross sections. The trashrack likely <br />does not meet current design criteria for opening sizes and flow velocities through the rack <br />and is considered unusable for reuse in the rehabilitation alternatives development. <br />3.2 Concrete Intake Tunnel <br />As previously described, the concrete intake tunnel is horseshoe shaped in cross section, 3 <br />feet wide by 5 feet high, and has a concrete floor. The tunnel is not perpendicular to the <br />intake structure or the embankment and follows a southwest bearing for approximately 100 <br />feet where it makes a gradual circular turn in a more southerly direction for approximately 25 <br />feet. The concrete tunnel then terminates and is followed by a rockcut tunnel for <br />