Ascension Parish, LA Environmental Rules: Erosion Control (2026)

Section 17-509 of the Ascension Parish Unified Land Development Code makes the project Engineer responsible for producing an ESC plan addressing sediment migration off the construction site, and makes the Contractor responsible for maintaining drainage ditches and detention ponds and providing bank stability and erosion protection until the site is fully stabilized. Any site that disturbs more than one acre must also carry a Louisiana Pollutant Discharge Elimination System (LPDES) storm water pollution prevention plan (SWPPP), filed with the Ascension Parish Engineering Department before construction starts and covered under general permit LAR100000 (over five acres) or LAR200000 (small construction).

The applicant deals directly with the Louisiana Department of Environmental Quality for permit specifics. Sites under LAR200000 must submit a small construction activity completion report within 60 days of finishing covered work, with a copy to the parish; sites under LAR100000 must file a notice of termination once the site is finally stabilized, also copied to the parish, and both permits require periodic inspection reports to the Ascension Parish Storm Water Department at the frequency set in the SWPPP. 5:1 if concrete-lined; storm water detention ponds are capped at 3:1 down to two feet below normal pool, steeper only with a licensed geotechnical engineer's stability certification; and open ditches are capped at 3:1. Where a ditch discharges into an outfall channel, it must be enclosed in a properly sized pipe approved by the Department of Public Works.