City of Manchester, MO Application

[Ord. No. 08-1852 §1, 2-19-2008; Ord. No. 09-1967 §2, 12-21-2009]

This Chapter shall be applicable to all subdivision or site plan applications, unless eligible for an exemption or granted a waiver by the City's Planning and Zoning Commission as listed below. The Chapter also applies to land development activities that are smaller than the minimum applicability criteria, if such activities are part of a larger common plan of development that meets the following applicability criteria, even though multiple separate and distinct land development activities may take place at different times on different schedules. In addition, all plans must also be reviewed to ensure that established water quality standards will be maintained during and after development of the site and that post-construction runoff levels are consistent with regional watershed plans. Possible exemptions or waivers include:

For development sites two thousand (2,000) square feet or less, the requirements of this Chapter may not apply.

For development sites from over two thousand (2,000) square feet to under one (1) acre, the Planning and Zoning Commission may waive these requirements so long as the amount of impervious cover created is less than forty percent (40%) of the total development site.

For development sites equal to or greater than one (1) acre, the development shall implement and enforce a program to address the quality of long-term stormwater runoff from new development and redevelopment projects. This includes projects less than one (1) acre that are part of a larger common plan of development or sale, that discharge into the permittee's regulated small MS4. The development shall ensure that controls are in place that have been designed and implemented to prevent or minimize water quality impacts by reasonably mimicking pre-construction runoff conditions by effectively utilizing water quality strategies and technologies to the maximum extent practicable. The developer shall assess site characteristics at the beginning of the construction design phase to ensure adequate planning for stormwater program compliance. The purpose for this approach is to arrive at designs and practices that provide for most effective water quality treatment through infiltration, flow rates and similar site-design opportunities. In addition to the SWPPP document submittal, a separate "post-construction runoff control program" shall be submitted. These documents shall include the following information at a minimum or as otherwise determined by the City's Planning and Zoning Commission.

A stormwater management strategy for the site must be developed to minimize water quality impacts, by reasonably mimicking pre-construction runoff conditions in affected new development and incorporating water quality protection in affected redevelopment projects to the maximum extent practicable and include a combination of structural and/or non-structural BMPs appropriate for the site. Development plans that consider the use of infiltration, evapotranspiration or water re-use such as grassed swales, bioretention cells, cisterns, green roofs, planter boxes, street retrofits, parking-lot infiltration or other approved measures are encouraged by the City.

A maintenance plan must be recorded under MSD's requirements to ensure adequate long-term operation and maintenance of selected BMPs.

The City of Manchester's strategy is to provide requirements and standards to direct growth to identified areas, protect sensitive areas such as wetlands and riparian areas, maintain and/or increase open space (including a dedicated funding source for open space acquisition), provide buffers along sensitive water bodies, minimize impervious surfaces and minimize disturbance of soils and vegetation will be through the implementation of the MSD "Site Design Guidance, Tools for Incorporating Post-Construction Stormwater Quality Protection into Concept Plans and Land Disturbance Permitting" in addition to implementation of the other elements of this Chapter and Code.

These regulations shall apply to all zoning districts of the City.

All uses, special and permitted, in the various zoning districts of the City shall comply with the procedures and standards of each respective District and of this Chapter. In the event of any conflict between the respective zoning district regulations and the regulations of this Chapter, the regulations, standards and procedures of this Chapter shall control.