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• 2,300 and 9,800 cfs respectively. Similarly, total runoff volumes <br />calculated using the same model are approximately 210 and 630 acre feet <br />for the 10 and 100-year storm events, respectively. <br />There is no available flow information for Second Alkali Creek since there <br />has been na monitoring to date and this drainage was not evaluated in the <br />original Dorchester permit submittal. Comparing the watershed area of 5.5 <br />square miles for Second Alkali Creek with the 2.4 square mile Magpie Creek <br />watershed and given similar topographic and drainage considerations, peak <br />flows and runoff for Second Alkali Creek are anticipated to be <br />approximately 2.5 times of those calculated for Magpie Creek. <br />Loadout Area. Drainages of local significance in the loadout and adjacent <br />areas include Oak and Chandler Creeks. Due to a relatively large <br />contributing drainage area, the upper portion of Oak Creek is considered <br />to be a perennial stream. However, significant withdrawals of surface and <br />• groundwater from the Oak Creek drainage system for municipal use by the <br />Town of Rockvale and agricultural use by downstream users results in <br />ephemeral or perennial flow characteristics for the lower portion of Oak <br />Creek. With the exception of recent monitoring by EFCI in the area of the <br />loadout, there is no historical information on flows for the lower portion <br />of Oak Creek. EFCI's monitoring data indicate flows varying from zero to <br />a maximum flow of 16 cfs, with ephemeral flows averaging less than three <br />(3) cfs as illustrated by Figure 8, Oak Creek Flow Hydrograph. As is true <br />of other area drainages, peak flow volumes normally occur during spring <br />snowmelt with sporadic peak discharge occurring in response to major <br />thunderstorm events. Other than the spring snowmelt period, and generally <br />low flows during the winter months, there is no distinctive pattern of <br />seasonal variation in flow volumes. <br />Chandler Creek is typical of other small ephemeral drainage in the area. <br />With a limited drainage area, Chandler Creek flows only in response to <br />snowmelt and major thunderstorm events. There is no historical monitoring <br />• data available for Chandler Creek and the stream is not currently <br />monitored as part of EFCI's ongoing monitoring program. EFCI has <br />evaluated the need to monitor Chandler Creek. The only drainage from the <br />loadout disturbance area which would reach Chandler Creek would be <br />2.04.7-31 <br />