Ord 2013-003/PDD for Capes Camp and Thompson's Island

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(TSS) after full development of the Property over the baseline existing conditions prior to development of the Property. The 85% TSS removal will be accomplished utilizing a combination of traditional Best Management Practices (BMP's) and approved LID practices designed in accordance with the TCEQ Edwards Aquifer Protection Program and the City of San Marcos LID manual. All BMP's shall be designed and maintained by the property owner to achieve the performance standard of 85% TSS removal. BMP's for treatment of stormwater proposed for this project may include, but shall not be limited to water quality ponds, rain gardens, bioswales, biofiltration ponds and native drought - tolerant plants for landscaping. Final design of all LID facilities /practices shall be subject to review and approval by the City. Approved vegetative buffers and filters shall not include invasive species. The BMP's shall be located as close as possible to the source of pollutants. Pollutant removal of 85% TSS shall be achieved by structural and non- structural LID practices focused on on -site, distributed, at the source controls, per the City of San Marcos Green Infrastructure — LID Practices Manual. End of pipe stormwater management systems shall only be used at the end of the network of structural and non- structural LID BMPs. LID techniques allow for greater development potential with less environmental impacts through the use of smarter designs and advanced technologies that achieve a better balance between conservation, growth, ecosystem protection, public health, and quality of life. Where feasible to achieve maximum water quality standards, the development of the Project shall incorporate various LID techniques, in one form or another, that will work in conjunction with traditional BMP's to achieve the 85% TSS removal indicated. The specific structural and non - structural LID practices proposed on the Project Site are as follows: • Catchment areas for filtration /infiltration of parking lot run -off in the form of biofiltration in larger areas and rain gardens with amended soils in smaller areas. • Catchment areas for filtration of roof run -off in the form of biofiltration in larger areas and rain gardens with amended soils in smaller areas. In some areas this could take the structural form of a planter box. • Grassy swales to convey the stormwater from the various collection points providing filtration /infiltration in addition to conventional conveyance • Grassy swales will widen to accommodate additional bioretention in -line or to the side (off -line) for additional filtration /infiltration • Sedimentation /filtration pond to be located away from River Road and is intended to be minimized by use of as many techniques as possible upstream of the pond and vegetative filter strip after the pond* • Flow spreader to return run -off to sheet flow conditions • Vegetative filter strip following flow spreader Additional LID techniques, as design constraints allow, will be implemented before the pond. The Project Site is limited to a maximum of 30% impervious cover of the total gross acreage of the Project Site in accordance with the requirements of the San Marcos River Corridor limitations under the LDC. Impervious cover may be clustered onto any portion of the Project Site, so long as the total impervious cover does not exceed 30% over the