430.160 Limited Exemptions Within an HCA.
The following activities within an HCA are exempt from the provisions of this Section except that a Construction Management Plan is required where the activity disturbs a total of more than 500 sq ft:
1. The alteration and/or total replacement of existing structures, provided that both of the following standards are met:
(a) The alteration and/or replacement shall not intrude more than 500 sq ft into the HCA, beyond the area defined as the building footprint.
(b) The alteration and/or replacement shall not result in increased direct stormwater discharges to a WQR.
2. Minor encroachments, not to exceed 500 sq ft for residential and nonresidential zones, for new features such as accessory buildings, patios, walkways, or retaining walls.
3. Temporary and minor clearing, excavation, or other disturbances, not to exceed 500 sq ft, for the purpose of: site investigations or preparation of soil profiles; installation of underground utility facilities or other infrastructure; routine repair and maintenance and/or alteration of existing utility facilities, access, streets, driveways, and parking improvements; or similar activities, provided that such disturbed areas are restored to their original condition when the activity is complete.
4. Low-impact outdoor recreation facilities for public use—including, but not limited to, multi-use paths, accessways, trails, picnic areas, or interpretive and educational displays and overlooks that include benches and outdoor furniture—provided that such facilities contain no more than 500 sq ft of new impervious surface.
5. Facilities that infiltrate stormwater on the site, including the associated piping, so long as the forest canopy and the areas within the driplines of the trees are not disturbed. Such facilities may include, but are not limited to, vegetated swales, rain gardens, vegetated filter strips, and vegetated infiltration basins. Native or nonnative vegetation may be planted in these facilities, provided that none of the plantings are identified as a nuisance species.