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<br />Long Hollow Reservoir <br />Feasibility Study <br /> <br />A U.S. Army Corps of Engineers (USACE) 404 Permit and a National Environmental Protection <br /> <br />Act environmental assessment are required because the project involves a live stream and <br /> <br />wetlands. <br /> <br />Two native fish, the roundtail chub and the flannelmouth sucker, are known to occur in the La <br />Plata River, downstream of Long Hollow. The Colorado Division of Wildlife (CDOW) <br />considers the roundtail chub to be a species of special concern, and the State of New Mexico lists <br />the fish as endangered. The Colorado Natural Heritage Program (CNHP) considers the <br />flannelmouth sucker to be a species of special concern. The La Plata Water Conservancy District <br />(LPWCD) is working with the CDOW to establish a monitoring and flow mitigation plan that <br />meets the requirements of the Compact while also meeting seasonal flow requirements for these <br />fish. <br /> <br />The USACE is coordinating the LHR 404 permitting process with federal agencies. The <br />proposed project will impact a total of 18,560 linear feet (LF) of perennial channel, including 2.5 <br />acres of emergent wetland active channel and 2,180 LF of ephemeral drainage. The LPWCD has <br />proposed the following wetland mitigation options: (1) wetland creation downstream of the LHR <br />embankment at a mitigation ratio of 1; 1 for the 2.5 acres of emergent wetland impact and (2) <br />mitigation of riparian corridor impacts by enhancing and/or restoring existing riparian areas <br />along Government Draw and the LHR. <br /> <br />A Clean Water Act (CW A) Section 404 Individual Permit Application was submitted to the <br />USACE in October 2003. Endangered Species Act Section 7 consultation is ongoing. The <br />consultation period has been extended three times and will conclude on April 14, 2005. A 45- <br />day period for issuance of a biological opinion by the U.S. Fish and Wildlife Service (USFWS) <br />will end on May 31, 2005. All other 404 Permit issues are being addressed by the LPWCD. <br /> <br />An open-channel spillway will convey flood flows around the left abutment of the dam. The <br /> <br />open-channel spillway has a 60-foot-wide low-flow channel at elevation 6,312 and a J80-foot- <br /> <br />wide channel with a control weir at elevation 6,319 feet. The operating flood pool of the <br /> <br />reservoir will be controlled by the low-flow channel, which can pass a 50-year storm. The PMP <br /> <br />991-077.120 <br />March 2005 <br /> <br />Wright Water Engineers, Inc. <br />Page 2 <br />