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<br />1) Average monthly flow over the 13-year period of data were <br />calculated. Although there were gaps in the information, there <br />were enough months with adequate data to generally compensate for <br />the missing months. Average annual flow from the basin during <br />this period was 2987 ac. ft. <br /> <br />2) The 13-year period of flow data was compared with the 57-year <br />period of flow data available on Plateau Creek. It was found that <br />the ratio of long-term flows to the 1986-93 flows was .974. After <br />adjusting the Rapid Creek flow data with this factor, the long-term <br />average flow was cal~ulated to be 2910 ac. ft. for the entire Rapid <br />Creek drainage. <br /> <br />c. Comparison of Roth Methods. <br /> <br />Hydrosphere decided to use the results from Method B for estimating <br />total basin yield. It was thought to be more accurate since it was based <br />on actual streamflow meallurements. <br /> <br />This approach gave total yield from the entire watershed. The <br />percentage of yield above the town's collection points calculated by <br />Method A was applied to Method B. This percentage (75.9) was <br />multiplied by the total yil\ld of 2910 AF to arrive at a yield above the <br />collection point of 2210 AF per year. <br /> <br />d. C'.a1culation of Dry and Wpt Year Flows. <br /> <br />Long term flow records from 5 adjacent streams with gauging stations <br />were used to estimate the ratio of dry year flow to average year flow. <br />Using the driest year on tecord (1977), a dry year to average year flow <br />ratio of .18 was calculated using the data from the 5 gauging stations. <br />This ratio is applicable only to surface flow. The ratio of dry year to <br />average year flow for sPTings was calculated using data compiled by the <br />local State Water Commi~sioner for the springs on Rapid Creek. The <br />dry year to average year ratio for springs is calculated to be .565. <br /> <br />The report also calculated fIrm yield for three 3 other hydrologic events <br />('moderate dry year' flows, 'wet year' flows and 'extreme wet year' <br />flows) using similar procedures. <br /> <br />4. Re.sults of Firm Yield Studies <br /> <br />Based on the methodology just described, the Hydrosphere report reported the <br />following amounts for yield from the Palisade watershed: <br /> <br />lV-16 <br /> <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />