13 2026 02 12 Crestmont CC Stormwater O and M Manual

maintenance work order and inspection checklist and logs have been provided in Appendix A and B of this manual. Actual maintenance work order and inspection checklists and logs shall be developed as part of the site stormwater facilities maintenance program. 4.0 CONSTRUCTED STORMWATER MANAGEMENT SYSTEM ELEMENTS The on-site stormwater management system includes best management practices (BMPs) designed to meet the stormwater quantity, quality, and groundwater recharge requirements for the project site, as well as series of subsurface conveyance systems comprised of precast inlets, manhole structures, drainage pipes, and riprap aprons, which convey stormwater runoff to and from the stormwater management BMPs and ultimately to the proposed off-site discharge points. 4.1 Stormwater Management BMPs The proposed redevelopment incorporates the following BMPs into the stormwater management design: 2 small-scale bioretention basins and 1 porous asphalt pavement system. Refer to Drawings CG103 and CG104 for the location of each proposed BMP; the table below lists each BMP proposed on the property that is subject to the requirements set forth in this maintenance plan. Table 1 – Summary of Proposed BMPs BMP Designation Type of BMP Location on Project Site Small-scale under-drained Southeast of the Laurel Ave and Eagle SSBB-1 bioretention basin Rock Ave intersection Small-scale under-drained East of the proposed driveway SSBB-2 bioretention basin connection to Eagle Rock Ave PAPS-1 Porous Pavement Parking Spaces south of SSBB-2 4.1.1 Small-Scale Bioretention Basins There are 2 small-scale bioretention basins proposed on the project site. The basins are comprised of a 24-inch thick soil media layer, underlain by a 6” thick sand layer and an underdrain collection system comprised of perforated 6” diameter HDPE pipes encased by a minimum of 3 inches of AASHTO #57 stone aggregate both above and below the collection system piping. A variety of ornamental grasses, plants, and shrubs are planted within the basin to promote uptake of pollutants and evapotranspiration. An outlet control structure

below the collection system piping. A variety of ornamental grasses, plants, and shrubs are planted within the basin to promote uptake of pollutants and evapotranspiration. An outlet control structure maintains specific water levels within the basins for each design storm event. 3