SWPPP Requirements in Missouri

Who needs a SWPPP in Missouri?

Any construction project that disturbs one acre or more — or is part of a larger common plan of development reaching one acre — needs a SWPPP under Missouri permit MO-RA00000 (construction or land disturbance master general permit (mo-ra00000)), or MO-R100000 (area-wide land disturbance master general permit (mo-r100000)).

Missouri runs its own delegated stormwater program. Operators obtain coverage from Missouri Department of Natural Resources (DNR), Water Protection Program under Missouri State Operating Permit — Master General Permit MO-RA00000 (Construction or Land Disturbance) (MO-RA00000 / MO-R100000), not directly from the EPA. A small subdivision, a solar pad, and a road-widening project all clear the same one-acre line.

Missouri adds requirements worth flagging early: A Missouri State Operating Permit that specifically identifies the project must be issued before any site vegetation is removed or the site disturbed (MO-RA00000 Part I.A.1) (MO-RA00000); Develop and implement the SWPPP before any land disturbance; it must be specific to the site's land disturbance activities (MO-RA00000 Part IV.1(a)) (MO-RA00000); Post a public notification sign with the site's specific MORA permit number at the main entrance, visible from the public road (or an alternate publicly visible location noted in the SWPPP), until the permit has been terminated (MO-RA00000 Part III.1) (MO-RA00000); Notify the land owner and each contractor or entity working on the site (including utility crews and city employees) of the SWPPP and the precautions to take on site; the permittee is responsible for damage subcontractors do to BMPs (MO-RA00000 Part III.2) (MO-RA00000); Designate an environmental lead with knowledge of erosion, sediment, and stormwater control principles, the permit, and the SWPPP; the environmental lead or a designated qualified inspector inspects the controls and signs each inspection report (MO-RA00000 Parts IV.8, IV.10, IV.12) (MO-RA00000); Include a sedimentation basin, sized at a minimum to treat the local 2-year, 24-hour storm, for each drainage area with ten or more acres disturbed at one time, or specify similarly effective BMPs where a basin is infeasible (MO-RA00000 Part V.11) (MO-RA00000); Remove sediment tracked onto roadways the shorter of either daily or before a rain event (MO-RA00000 Part III.9(d)) (MO-RA00000); Report an unauthorized discharge that reaches waters of the state to the regional office as soon as practicable but no more than 24 hours after discovery (after hours: Environmental Emergency Response hotline, (573) 634-2436); keep a record of all spills with the SWPPP (MO-RA00000 Part III.16) (MO-RA00000); Before removing BMPs, ceasing inspections, or terminating coverage, achieve final stabilization (perennial vegetation at 70% coverage of 100% of vegetated areas, evenly distributed, or permanent materials) and document its type and date in the SWPPP (MO-RA00000 Part V.13) (MO-RA00000); If the project will be completed after the permit's expiration date, reapply for a new permit; the permit does not continue administratively beyond its expiration date (MO-RA00000 Parts VIII.4(b), VIII.5) (MO-RA00000); Sites within 1,000 feet of an Outstanding National or State Resource Water or a water impaired for sediment operate as no-discharge facilities (MO-RA00000 Part I.B.3(c)) (MO-RA00000); Terminate coverage with a Request for Termination of Operating Permit (Form MO 780-2814) to the regional office once Part VI.1 is met (MO-RA00000 Parts VI.1, VIII.4(a)) (MO-RA00000); A Missouri State Operating Permit that specifically identifies the project must be issued before any site vegetation is removed or the site disturbed (MO-R100000 Part I.A.1) (MO-R100000); Develop and implement the SWPPP before any land disturbance; it must be specific to the site's land disturbance activities (MO-R100000 Part IV.1(a)) (MO-R100000); Post a public notification sign with the site's specific MOR100 permit number at the main entrance, visible from the public road (or an alternate publicly visible location noted in the SWPPP), until the site is finalized (MO-R100000 Part III.1) (MO-R100000); Notify the land owner and each contractor or entity working on the site (including utility crews and city employees) of the SWPPP and the precautions to take on site; the permittee is responsible for damage subcontractors do to BMPs (MO-R100000 Part III.2) (MO-R100000); Designate an environmental lead with knowledge of erosion, sediment, and stormwater control principles, the permit, and the SWPPP; the environmental lead or a designated qualified inspector inspects the controls and signs each inspection report (MO-R100000 Parts IV.8, IV.10, IV.12) (MO-R100000); Include a sedimentation basin, sized at a minimum to treat the local 2-year, 24-hour storm, for each drainage area with ten or more acres disturbed at one time, or specify similarly effective BMPs where a basin is infeasible (MO-R100000 Part V.11) (MO-R100000); Remove sediment tracked onto roadways by the same business day, or by the end of the next business day if track-out occurs on a non-business day, and before predicted rain events (MO-R100000 Part III.7(d)) (MO-R100000); Report an unauthorized discharge that reaches waters of the state to the regional office as soon as practicable but no more than 24 hours after discovery (after hours: Environmental Emergency Response hotline, (573) 634-2436); keep a record of all spills with the SWPPP (MO-R100000 Part III.14) (MO-R100000); Before removing BMPs, ceasing inspections, or terminating coverage, achieve final stabilization (perennial vegetation at 70% coverage of 100% of vegetated areas, evenly distributed, or permanent materials) and document its type and date in the SWPPP (MO-R100000 Part V.13) (MO-R100000); If the project will be completed after the permit's expiration date, reapply for a new permit; the permit does not continue administratively beyond its expiration date (MO-R100000 Parts VIII.4(b), VIII.5) (MO-R100000); The area-wide permittee submits a quarterly report through the Department’s eDMR system (via MoGEM) listing each active land disturbance site, including off-site borrow or depositional areas: project name, location and county, primary receiving water(s), description, acres disturbed, percent complete, and projected completion date — due April 28, July 28, October 28, and January 28 (MO-R100000 Parts VII.2–3, Table A) (MO-R100000); A site is finalized and removed from coverage once Part VI.1 is met; the permit itself is terminated with the final quarterly report when all covered projects are finalized (MO-R100000 Parts VI.1–2) (MO-R100000).

What the plan must contain

A Missouri SWPPPis the site's compliance binder — the document an inspector opens first. It documents:

1. 1Site & project descriptionTotal and disturbed acreage, soils, slopes, and the sequence of construction.
2. 2Receiving waters & discharge pointsWhere stormwater leaves the site and the waterbodies it reaches.
3. 3Erosion & sediment control BMPsSilt fence, stabilized entrances, inlet protection, and stabilization measures.
4. 4Inspection schedule & recordsDated, signed inspection logs and the corrective actions taken.
5. 5Operator certificationThe SWPPP is signed by the legally responsible party before work begins.

Required and conditional BMPs

Filing your Notice of Intent

Apply for the site’s MO-RA land disturbance permit through the Department’s ePermitting system after registering a Missouri Gateway for Environmental Management (MoGEM) account (Fact Sheet, “ePermitting for Land Disturbance”). There is no separate NOI: the permit that specifically identifies the project must be issued before any disturbance of the root zone or other land disturbance begins (Part I.A.1). Terminate with Form MO 780-2814 (Part VIII.4(a)).

A Notice of Termination closes coverage once the site reaches final stabilization. Keeping the SWPPP and its inspection records on site is what keeps a project clear of stop-work orders.

Inspection requirements

The permit allows 2 inspection schedules; the operator follows one and records the choice in this plan: (a) 7-day schedule with 2-year, 24-hour storm inspections — inspect at least once every 7 calendar days and within 48 hours after the end of any storm event equal to or greater than a 2-year, 24-hour storm (the 48 hours run from when the storm has ceased during a normal work day; if the rain event ceases during a non-work day such as a weekend or holiday, inspect within 72 hours) (MO-RA00000 Part IV.11(a)); or (b) 14-day schedule with 0.25-inch storm inspections — inspect at least once every 14 calendar days and within 24 hours of the occurrence of a storm producing 0.25 inch of rain or more (or within 24 hours of the occurrence of runoff from snowmelt; the inspection is conducted within 24 hours of the event end, or within 72 hours if the rain event ceases during a non-work day such as a weekend or holiday; for a storm that continues for multiple days with 0.25 inches or more each day, inspect within 24 hours of the end of the storm (72 hours if it ceases on a non-work day); inspections are only required during the project’s normal working hours; storm depth comes from a properly maintained on-site rain gauge or a weather station near the site) (MO-RA00000 Part IV.11(b)). The chosen frequency is documented in the SWPPP, and any change of frequency, including switching between options (a) and (b), is documented on the inspection form (Part IV.11); areas that have achieved stabilization while construction continues elsewhere may be inspected monthly (temporarily stabilized areas return to the (a), (b), or (c) frequency when re-disturbed; finally stabilized areas are inspected at least once per month until the permit is terminated) (Part IV.11(d)); when construction is suspended for frozen conditions, land disturbance has stopped, and all disturbed areas are stabilized, inspections may be reduced to monthly until thawing begins, noted in the SWPPP (Part IV.11(e)); basin dewatering is inspected daily while discharging (Part IV.11(f)). Every inspection is dated and signed, and any failed control is corrected before the next storm.

How Missouri differs from the federal permit

Because Missouri administers its own program, the federal EPA Construction General Permit does not apply directly here — the state permit governs. Sites inside a regulated municipal storm sewer system may carry additional local ordinance requirements on top of the state permit.

Frequently asked questions