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JUL -08 -2002 MON 09;12 AM <br />FAX NO, <br />P. 12 <br />s five - consecutive day exeeedalice (8,300 to 10,800 cfs) and 30- consecutivc- <br />clay cxceedance (3,400 cfs). <br />Oclohcr 1994 [JSI;WS estimates an average of 417,000 AF /year of historic instrearn flow <br />shortages relative to the Service's instream flow recornniendations <br />(document dated October 17, 1994). This estimate was based oaf p,n <br />analysis of eiaily flows at Grand Island front 1943 to 1992 relative to <br />recon-Ime-nded species flows and annual pulse flows. <br />March 1996 Yon Altenhofen (Northern Colorado Water Conservancy District) propose:~ <br />a method for "more specifically quantifying the duration, magnitude, alld <br />frequency" orthe USFWS instream flow recommendations for the *May- <br />J tme period. (memo to the Platte River Technical Group, March 4, 1996). <br />These flow valties were adopted by IJSP WS to ,score" the Proposed <br />Program and alternatives in terms of their ability to reduce shortages to <br />Prograan target flows on a monthly weighted- average basis (Attachment <br />E). These are used in subsequent proposed project evaluations mid <br />consultations, including the Kingsley Dane Biological Opinion (1997). <br />July 1997 Platte !fiver Cooperative Agreement is signed by the three state governors <br />and the oecrotary of the Interior. A specific objective articulated in the <br />Cooperative Agreement is to improve "the occurrence of Platte River <br />• flows in the associated habitats relative to the present occurrence of target <br />flows (hereinafter referred to as `roducing shortages to the target flows') <br />by an average of 130,000 to 150,000 acre-feet per year ", The term "target <br />Rows" is footnoted with a reference to the May 23, 1994 and August 3, <br />1094 TJSEVS documents. <br />Docemt. or 1999 Boyle l;nginccrino Corporation delivers their final Platte Rivet Plattc <br />.River [Vater° Ct)nservaIi0Y7 1SuI)I)ly Reconnaissance Study to the Watel- <br />Management Committee. in determining the hydrological effects of a <br />specific project, Hoyle assumed that diversion to recharge or storage are <br />made "only during periods of target flow excesses at the critical habitat" <br />and that releases for the benefit of the critical habitat are "only made <br />during periods of target flow shortages ". The "target flows" used by Boyle <br />for this assessment were the same inontlaly weighted- average species flow <br />.end pulse now recommendations used by the USFWS and the <br />I'rogrant since 1996. <br />J,mii, try 2001 The 1.J.S. Bureau of Reclamation (Murphy and Randle) release a report <br />( "1'lattic River Channel: History and Restoration") that describes <br />anti eip. -Jod continued erosion of medium -sized sand and chamicl <br />narrowing downstream from Grand Island, Nebraska over tale next several <br />decades without changes in management of the river, and recoinrncnds <br />short- duration (one to three days) vegetation - scouring flows as one <br />11 <br />