Laserfiche WebLink
The upfront stormwater assessment and planning processes implemented at the project submittal stage <br />will include guidance and recommendations for projects to include volume management features at the <br />most ideal locations throughout a project's corridor. At a minimum, the City will look to provide <br />pretreatment of stormwater before it enters the existing stormwater system. <br />7.2.1 RUNOFF RATE <br />Goal: Control the rate of surface water runoff from development to reduce downstream flooding and <br />erosion. <br />Policy 1: Adopt RCWD Rule C by reference. Develop Comprehensive Stormwater Management Plans <br />(CSMP) for required stormwater management as an alternative to meeting the requirements <br />of RCWD Rule C, Sections 6 and 7. The RCWD is required to approve any CSMP. Review and <br />update City code to reflect this policy. <br />Policy 2: As the City is entirely located within the RCWD's defined Flood Management Zone, peak runoff <br />rates from regulated new development, redevelopment, or site expansion projects shall not <br />exceed 80% of existing rates for the 2-year, 10-year, and 100-year rainfall events. Rate <br />control below existing rates may be necessary where downstream capacity issues are <br />identified, which will require coordination with the RCWD and adjacent municipalities. <br />Policy 3: Coordinate with RCWD to ensure stormwater practices are implemented to prevent increases <br />in peak runoff rates at RCWD-designated intercommunity flow locations. Intercommunity flow <br />locations are shown with arrows at the City boundary on Map 1. Specific intercommunity flow <br />rates identified in the RCWD District -wide model are tabulated below. It is anticipated that <br />implementing the City's adopted ordinances will reduce intercommunity flow rates under full <br />build -out conditions. <br />Peak Flow <br />(cfs) <br />Discharging <br />Receiving <br />watercourse <br />2-Year, 24- <br />10-Year, 24- <br />100-Year, 24- <br />100-Year, 10- <br />City <br />City <br />Hour Rainfall <br />Hour Rainfall <br />Hour Rainfall <br />Day Snowmelt <br />Arden Hills <br />Mounds <br />Rice Creek <br />215 <br />421 <br />957 <br />1377 <br />View <br />Mounds <br />ARJD 1 Main <br />89 <br />Blaine <br />View <br />Trunk <br />47 <br />74 <br />100 <br />Mounds View <br />New <br />Rice Creek <br />230 <br />443 <br />958 <br />1376 <br />Bri hton <br />ARJD 1 Main <br />Mounds View <br />Shoreview <br />Trunk <br />42 <br />59 <br />114 <br />118 <br />Policy 4: Require that the maximum duration for rainfall critical event analysis shall be 24 hours. <br />Require the use of the hydrograph method of analysis and NOAA Atlas 14 rainfall amounts <br />and distribution. <br />City of Mounds View 38 <br />Local Surface Water Management Plan Stantec Project No. 193804166 <br />5ta nte+c <br />