Clayton staff proposes tighter stormwater rules, minimum green‑space and new inspection requirements

Anna (plan development staff) presented a multi‑part package on June 10 to the Clayton City Board of Aldermen that would separate the city’s existing single regulation on “lot coverage” into two distinct tracks: (1) a minimum green‑space requirement aimed at preserving neighborhood character and reducing urban heat island effects, and (2) a revised stormwater standard focused on more prescriptive on‑site detention and monitoring.

The packet staff described includes several engineering and code changes recommended by Intuition and Logic, the city’s on‑call stormwater consultant. Anna said the changes would “increase the differential detention requirement from a 15‑year, 20‑minute storm to a 100‑year, 60‑minute event” and add inspection and tracking steps for common best management practices (BMPs) such as dry wells. She told the aldermen the goal is to reduce impervious runoff while preserving natural vegetation and neighborhood open space.

The proposal would: require a larger detention volume on many redevelopment lots by using a 100‑year/60‑minute design storm for differential runoff calculations; require infiltration testing for dry wells and expand dry‑well footprints when soils are slow to infiltrate; formalize a deed‑recorded inspection form and two‑year inspection reporting for many BMPs; clarify that certain sustainable materials (for example,…