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Mr. Blair, P.E. <br />February 11, 2004 <br />Page 3 <br />The total length of the outlet conduit is about 365 feet from the upstream end to <br />the gate valve in the pump station located at the toe of the dam. The inspection of <br />the downstream third of the pipe was hindered somewhat by the presence of water <br />in the bottom of the pipe. This water could not be drained due to the configuration <br />of the piping in the pump station at the discharge end of the outlet. This water <br />prevented the inspection of the bottom portion of the pipe and also prevented <br />inspection of the last 10 feet of the outlet pipe on the pump station end. The <br />inspection tape ends at 357 feet into the outlet, which is well through the <br />embankment portion of the dam. <br />After completion of the video inspection, direct visual inspection of the upstream <br />end of the conduit revealed minor deterioration of the cement lining in the bottom of <br />the outlet conduit. The deteriorated section started about 2 feet into the conduit <br />and extended for about 4 or 5 feet. This deteriorated section should .be patched <br />when the reservoir is cleaned and the outlet is put back into service. <br />Intake Structure <br />With the outlet structure exposed, it was possible to conduct a detailed inspection <br />of the structure. As shown on the as-built drawings of the dam that were <br />previously transmitted to you on CD, the intake structure is a concrete structure <br />with metal trashracks. The trashracks appeared to be in fair condition with minor <br />corrosion. The concrete structure showed signs of deterioration, primarily along the <br />edges of the walls and trashrack support beams where spalling is most significant. <br />This deterioration is shown on the attached photos. Although the deterioration <br />does not appear to be compromising the integrity of the structure at this time, ,s <br />rehabilitation of the structure should be considered in the future. The attached <br />photos 3 and 4 show the condition of the concrete structure. <br />