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<br />.. Water Supply and Storage Company <br />. Page 4 <br /> <br />DAM SAFETY <br /> <br />The planning and design of Long Draw Dam and Reservoir, including the outlet works, were <br />performed in accordance with all U.S. Bureau of Reclamation (USBR) dam safety criteria. <br />The design was carefully reviewed and monitored by the USBR through the entire design <br />process. The USBR also monitored the construction phase of the work. <br /> <br />Special attention was paid by the USBR to the dam. outlet works design and construction <br />because it was known that there would be long periods with no dam. tender on duty and that <br />outlet works failures are a common cause of dam failures. One such dam failure was the <br />1982 collapse of Lawn Lake Dam to the south of Long Draw Dam which resulted in <br />extensive property ti~m~ee in Rocky Mountain National Park and all the way through Estes <br />Park, even though the water in storage was no more than 777 acre-feet. <br /> <br />Relative to the outlet works, the design and construction approach was based on having the <br />gates closed for the winter period for safety-related reasons. The U.S. Forest Service <br />(USFS) (May 22, 1968) and the U.S. Fish and Wildlife Service (USFWS) (May 10, 1968) <br />both acknowledged the winter gate closing at Long Draw in their project review letters and <br />found the permanent fIsheries and recreation pool to be. a valuable improvement in the <br />fIShery resource in the project area. The agency approval for the winter closing of the gates <br />was relied upon when the design criteria for the dam was developed by Wright Water <br />Engineers. The USFS recommended against fishery releases as follows: <br /> <br />The outlet gates will usually be closed from November to July. It is anticipated <br />that seepage from the dam will equal or exceed the natural winter inflow to the <br />reservoir, thereby providingfor jish survival in the downstream channel to the <br />point where other tributary drainages will augment the flow. The remote <br />location precludes winter outlet-gate manipulation which would ordinarily be <br />required to support downstream fish habitat by release of the small natural <br />winter inflow. Furthermore, winter storage in the reservoir will improve <br />fishery conditions in the permanent pool. For these reasons,jishery releases are <br />not recommended. (Italics inserted by writer.) <br /> <br />The USFWS stated that seepage flows in the Long Draw Creek (aJkJa La Poudre Pass <br />Creek) would approximate the seepage from the dam during certain periods of the year. <br />Relative to fisheries, they stated the following: <br /> <br />La Poudre Pass Creek supports a small population of cutthroat trout and <br />brook trout and attracts a fe~ fIShermen. Long Draw Reservoir usually is <br />drained each year; consequently, fishing is insignificant in the reservoir. <br />Likewise. the amount of flows in Long Draw Creek downstream of the reservoir <br />approximates the seepagefrom the dam during cenain periods of the year. A few <br />