Waynesville, MO Environmental Rules: Stormwater Management (2026)

Chapter 410's Article IV, adopted by Ordinance No. 985 on June 17, 1999, and amended by Ordinance No. 1211 in 2005, requires a stormwater management plan under Section 410.110 with every land disturbance permit application, prepared and certified by a professional engineer licensed in Missouri, covering stormwater drainage and stormwater detention components. No storm drainage facility can be built, altered or reconstructed without a separate permit from the Building Official, and no certificate of occupancy or subdivision plat is issued until the approved storm drainage facilities are complete, unless a performance bond covers the gap.

Section 410.120 fixes the engineering standard: all detention facilities must hold the runoff from a 25-year return frequency, 24-hour duration storm, and must be designed so that post-development peak runoff does not exceed pre-development peak runoff for the 2, 10 and 25-year, 24-hour storms, with the whole site protected against a 100-year storm event. Section 410.130 requires stormwater detention for every site larger than two acres unless the developer pays a fee in lieu of building it, set at $500 per acre in residential zones and $1,500 per acre in commercial or industrial zones, both with the stated minimums, credited to the City's Stormwater Improvement Fund.

Failure to maintain a storm drainage facility is declared a nuisance under Section 410.190, giving the Building Official authority to order abatement and, if the owner does not comply, to certify the cost as a special tax bill against the property.