Specific stormwater management plans will be required with any major modifications of any parcel, platting, or Pc applications for new structures. These plans will demonstrate compliance with the approved PUD master stormwater management plan, on file with the city. The developer will have said specific stormwater management plans prepared by a professional engineer licensed in the state of Iowa, prior to the submittal of any specific development proposals within the PUD. The method of stormwater management and the stormwater conveyance system shall be established as follows:
Phase I: The first phase will consist of the construction of detention facilities in drainage basins 2 and 3A (basin map on file with the city) to limit the discharge of the site to the 5-year developed storm. The first phase will be completed with the first development modification for parcel A and/or parcel B, including, but not limited to, new buildings, variances, building additions whether done by minor modification or major modification and parking lot modifications and excluding facade changes.
Phase II: The second phase will consist of the construction and expansion of detention facilities in drainage basin 3B to limit the discharge of the site to a level between the 5-year development storm and the 5-year undeveloped storm. The second phase will be accomplished with the second major modification of the site plan or permitted conditional use permit for which building modifications or site modifications are proposed for parcel A and/or parcel B or by December 31, 2025, whichever occurs first.
Phase III: The third phase will consist of the construction of detention facilities in drainage basin 1 to limit the discharge of the site to the 5-year predeveloped storm. The third phase will be accomplished with the third major modification of the site plan or permitted conditional use permit for which building modifications or site modifications are proposed for parcel A and/or parcel B, or by December 31, 2030, whichever occurs first. (Ord. 2056, 10-6-2014)