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<br />model of the,collection system MWMC is able to estimate the current peak flow. DEQ <br />defines the peak flow as the peak hour or peak instantaneous flow that occurs during the <br />5-year, 24-hour storm (3.9 inches of rainfall). Under these rainfall conditions, the model <br />. predicts a curreI)t flow of 264 mgd. Therefore, there is no available capacity in terms of peak <br />flow. Since the 'current average fl9W is 43.8 mgd, the current wet season III is 220.2 mgd <br />. (264 less 43.8). <br /> <br />Using the projected future 2025 population and land, use, the model predicts peak .flows of <br />294' mgd without III reduction efforts outlined in the 2000 WWFMP and 277 m:gd with III <br />reduction effortsou~ed in the 2000 WWFMp. Therefore, it is estimated that'the III <br />reduction efforts will reduce III by approximately 17 mgd. <br /> <br />Wet season III in 2025 attributed to existing users is determined by ~ubtracting the <br />anticipated reduction in wet season III (17 mgd) from the current wet season III <br />(220.2 mgd) yielding 203.2 mgd. <br /> <br />Finally, wet season III attributed to growth in 2025 is 14.5 mgd and is determined by taking. <br />'the 2025 total peak flew projection of 277lllgd and subtracting both the 2025 average flow <br />(59.3mgd) and the 2025 wet season III attributed to existing users (203.2 mgd). Therefore, <br />the peak flow in 2025 attributed to growth is 30 mgd (15.5.mgd of average flow plu~ 14.5 of <br />wet season III flow). <br /> <br />TABLE C.2 <br />Projecled'2025 Peak Flow Breakdown <br /> <br />Average flow attributed to . existing, users (includes dry <br />season III) <br /> <br />Average flow attributed to future,users (includes'dry <br />season III) <br /> <br />Wet season III attributed to existing users <br /> <br />Wet season tll attributed to future users <br /> <br />. Total pe~k flow <br /> <br />Total peak flow attributed to growth <br /> <br />43,,5 mgd <br /> <br />15.5 mgd (59.3 - 43.8) <br /> <br />203.2 mgd (220.2 - 17) <br />14.5 mg~ (277 - 59.3 - 203.2 <br />277 mgd <br />30 mgd (15.5 +"14.5) <br /> <br />BOD <br /> <br />The methodology for BOD is similar to that of average flow. The existing capacity, although <br />not explicitly stated in the current NPDES ,permit, is 66,000 lbsl day, whiCh was the value <br />used for th~original WPCF deSign. The current loading or current required capacity in <br />presented in DSMM terms is 54,800 lbs/day and is determined as follows: <br /> <br />Current BOD = (0.185 x 217,737 x 1.3)' + 2,402 = 54,800 lbsl day (~c~al calculated value of <br />54,75611:>sl day rounded to the nearest hundred pounds). <br /> <br />Where: <br /> <br />A-29 <br />