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Whetstone <br />Associates Technical Memorandum <br />2013, the pond had a maximum surface area of 0.068 acres. The pond surface <br />dimensions are approximately 45 ft by 85 ft feet, with a total pond volume of 12,512 ft3 <br />(0.287 acre -ft) and a depth of 7.5 ft from the pond floor to the rim. The sides slope at <br />0.59 ft /ft, or approximately 1.7:1. Based on the 7.5 -ft distance from the pond floor to <br />the rim, the pond is a non - jurisdictional ponds. <br />SWRP4n2 <br />SWRP -In1 <br />t <br />Eleffn <br />QL! T <br />4 g x S O <br />. 7 PWt <br />Elerm <br />MOU m/e <br />MFA <br />MF <br />Road <br />�r etention Pond <br />,Is <br />MFA <br />Figure 2. Stormwater Retention Pond Survey Contours — May 2013 <br />The proposed design for the SWRP involves expanding the pond to the north - northeast, <br />installing a spillway crossing an existing dirt road, and deepening the excavation to <br />eight feet below the spillway elevation. Based on the 8 -ft maximum planned depth <br />below the planned spillway, the expanded pond will also be a non - jurisdictional pond. <br />10. Page 24, Section 5.2 and Tables 14 and 15. This section discusses diversion channel <br />capacity. Table 14 suggests all channels are designed or constructed to be a minimum 5.0 <br />feet in depth. The DRMS could find no flow velocity evaluation in this submittal. <br />a. Please confirm all listed channels have a minimum design or constructed depth of 5.0 <br />feet or provide a summary of minimum design /constructed depths. Your response should <br />include stamped and signed design and/or as -built drawings indicating these depths. <br />b. Please provide stability analysis results indicating design flow velocities are either less <br />than or equal to five feet per second or channel protection is designed and/or placed with <br />A "jurisdictional dam" has a reservoir capacity of greater than 100 acre -feet or reservoir surface area greater than 20 acres at the high -water line, or <br />one that exceeds 10 feet in height from the bottom of the excavation (or lowest point of the natural surface of the ground, if not excavated) to the <br />crest of the emergency spillway. A "non- jurisdictional dam" is smaller than these dimensions and is regulated under sections 37 -87 -102 and 37 -87- <br />105 of the Colorado Revised Statutes (C.R.S.) <br />4148A.131030 6 <br />