Laserfiche WebLink
<br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br /> <br />have been eroded away exposing the reinforcing steeL Riprap do~mstream of <br />the concrete structure is adequately si zed but not properly chi nked, allowing <br />erosion to occur between the blocks. <br /> <br />2.3.2 Hourglass Outlet Works <br /> <br />The Hourglass outlet works, which is at approximately elevation 9367 <br />(G.H. 12), feeds water into the Hourglass feeder canal for transfer to <br />Hourgl ass Reservoi r. The outl et works ori gi nally consi sted of a 36x48-i nch <br />arch shaped concrete conduit with a wet well near the center of the dam rising <br />to the crest. The conduit was extended 30 feet do~mstream wi th 36-i nch <br />rei nforced concrete pi pe and upstrea~ 35 feet usi ng 36-i nch di ameter steel <br />cul vert pipe in 1966. Only the transi ti ons from concrete to steel and from <br />one steel section to the other were encased in concrete. The original <br />concrete arch secti on has been patched several times over the years \'1ith <br />mortar. The intake to the outlet conduit is flush with the reservoir bottom <br />and the opening is protected by a steel trash rack. A concrete energy <br />dissipator is located at the downstream end of the conduit. Flow through the <br />conduit is controlled from the crest by a ~anually operated slide gate located <br />at the downstream side of the wet well. <br /> <br />Inspection of the inlet, wet well, and conduit revealed them to be in poor <br />condition. A log of the inspection is included in Appendix A. The inlet <br />structure is clogged with driftwood debri s both outsi de the trash rack and <br />inside the inlet chamber. Sand and gravel debris has also been deposited on <br />the invert of the inlet structure. The steel pipe is bulged, dimpled, and <br />twisted in several locations and the coal tar epoxy liner has been cracked and <br />chipped away at nUr.1erous points, particularly at the joints below the spring <br />1 i ne. The upstream connecti on between the steel transiti on secti on and the <br />steel pipe extension has been slightly flattened to a horizontal oval shape. <br />At the downstream end of the steel extension, the pipe was deformed to a <br />vertical oval in order to fit into the concrete arch. The concrete section <br />just downstrear.1 of the steel pipe but upstrear.1 of the wet well has various <br />defects in the concrete including spal1s, cracks, and porous concrete that is <br /> <br />2084H <br /> <br />-7- <br />