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<br />OD3Jl2 <br /> <br />METRICS FOR STREAM GAGING GOALS <br /> <br />There is associated with each goal, a metric to quantify the goal, thereby allowing evaluation <br />of the existing network of USGS gages, as well as compatible gages supported by other agencies, <br />in meeting that goal. Furthermore, from this analysis, the number of additional gages needed to <br />supplement the existing network so each goal is fully met can be determined, The metrics and <br />inventory of gages existing or needed to meet each of the fourteen stream gaging goals is presented <br />in the table below. A total of 18,330 gaging stations are estimated to be required to meet the over <br />30,000 coverage requirements needed for the fourteen goals. A number of the gages would help <br />meet more than one goal as indicated: <br />Number of Gaging Stations <br />149 <br />],800 <br />4,170 <br />12,210 <br /> <br />Number of Goals Met <br />Over 5 <br />3 or 4 <br />2 <br />I <br /> <br />FINDING 8 - DON'T USE BROAD METRICS FOR EV ALUA TING STREAM GAGING GOALS <br /> <br />While the workshops did not produce any significant and specific new or modified metrics <br />for these goals, there was considerable concern about the threshholds used in many of the metrics <br />to filter the gage coverage necessary to accommodate the goals, For example, the water diversion <br />goal's standard of diverting 25% of the mean annual flow ofa river was felt to be too coarse for <br />meaningful management considerations, exemplified by the small number of gages required to meet <br />the goaL Similarly, applying the reservoir goal to projects over 50,000 acre-feet was seen as <br />limiting. The use of HUC-6 hydrologic accounting units overlooked the smaller scale watersheds <br />of real concern as well as representative streams, There is a strong advocacy for conducting case-by- <br />case evaluation of gage coverage for meeting specific goals as opposed to using broad metrics <br />meeting national perspectives of information needs, <br />