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I I I I I I I I I I I I I I I I I I I evi dence of i nfi 1 trati on from the embankment into the condui t. The wet well and gate appeared to be in good operating condition. The wooden planking at the top of the wet well has been replaced recently by the City. The invert of the original concrete arch downstrea~ of the wet well was uniformly eroded to a depth of two to three inches with large aggregate exposed and protruding up into the conduit. Minor erosion along feathered edges at the horizontal construction joints, as described for the ~ain conduit, was observed, as well as mi nor spall i ng and cracki ng, and secti ons of porous concrete in the crown of the arch. Seepage water under hydrostatic pressure, even with the reservoir drained, was observed flo\ting into the conduit at several locations. The energy dissipator at the downstream end of the conduit was in good condition except for accu~ulation of sand and gravel on the invert. 2.4 Spillways 2.4.1 Service Spillway The exi sti ng servi ce spill way is a riprap 1 i ned channel about 100 feet wide with a control elevation of 9390 (G.H. 35.0). It is located at the right abutment of the embankment dar.1. The channel slopes gently and curves to the 1 eft di schargi ng into Hourgl ass Creek about 250 feet downstrea~ of the dam. The spillway appeared to be in good condition. An accu~ulation of dead trees upstream of the log boom occurs every year at the high water mark and the City periodically collects and burns the debris. 2.4.2 Auxiliary Spillway The existing auxiliary spillway is a 200-foot wide section of the embankment da~ adjacent to the spillway at elevation 9394 (G.H. 39.0), one foot 10~/er than the dam crest. Although the lowered crest would probably cause the dam to breach in that section prior to the main part of the dam, the breach would likely be uncontrolled and could possibly result in the same magnitude of damage as if the dam were to fail at any other point. 2084H -8-