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five- consecutive day exceedance (8,300 to 10,800 cfs) and 30- <br />consecutive -day exceedance (3,400 cfs). <br />October 1994 USFWS estimates an average of 417,000 AF /year of historic instream <br />flow shortages relative to the Service's instream flow recommendations <br />(document dated October 17, 1994). This estimate was based on an <br />analysis of daily flows at Grand Island from 1943 to 1992 relative to <br />recommended species flows and annual pulse flows. <br />March 1996 Jon Altenhofen (Northern Colorado Water Conservancy District) proposes <br />a method for "more specifically quantifying the duration, magnitude, and <br />frequency" of the USFWS instream flow recommendations for the May - <br />June period (memo to the Platte River Technical Group, March 4, 1996). <br />These flow values were adopted by USFWS to "score" the Proposed <br />Program and alternatives in terms of their ability to reduce shortages to <br />Program target flows on a monthly weighted- average basis (Attachment <br />E). These are used in subsequent proposed project evaluations and <br />consultations, including the Kingsley Dam Biological Opinion (1997). <br />July 1997 Platte River Cooperative Agreement is signed by the three state governors <br />and the Secretary 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 `reducing shortages to the target flows') <br />by an average of 130,000 to 150,000 acre -feet per year ". The term "target <br />flows" is footnoted with a reference to the May 23, 1994 and August 3, <br />1994 USFWS documents. <br />December 1999 Boyle Engineering Corporation delivers their final Platte River Platte <br />River Water Conservation /Supply Reconnaissance Study to the Water <br />Management Committee. In determining the hydrological effects of a <br />specific project, Boyle 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 <br />Boyle for this assessment were the same monthly weighted- average <br />species flow and annual pulse flow recommendations used by the <br />USFWS and the Program since 1996. <br />January 2001 The U.S. Bureau of Reclamation (Murphy and Randle) release a report <br />( "Platte River Channel: History and Restoration ") that describes <br />anticipated continued erosion of medium -sized sand and channel <br />narrowing downstream from Grand Island, Nebraska over the next several <br />decades without changes in management of the river, and recommends <br />short- duration (one to three days) vegetation- scouring flows as one <br />10 12 <br />