SWPPP Requirements in Connecticut

Who needs an SPCP in Connecticut?

Any construction project that disturbs one acre or more — or is part of a larger common plan of development reaching one acre — needs an SPCP under Connecticut permit CTR100000.

Connecticut runs its own delegated stormwater program. Operators obtain coverage from DEEP under General Permit for the Discharge of Stormwater from Construction Activities (CTR100000), not directly from the EPA. A small subdivision, a solar pad, and a road-widening project all clear the same one-acre line.

Connecticut adds requirements worth flagging early: Stormwater Pollution Control Plan (SPCP) prepared under Section 5.2, consistent with the Connecticut Guidelines for Soil Erosion and Sediment Control and the Stormwater Quality Manual; submitted with the application in PDF and posted at a public URL for the permit term (Section 3.4.1.10); Design certification by a Connecticut-licensed professional engineer or landscape architect (Section 2.2.14); Locally Approvable projects add a Conservation District or Qualified Professional plan review certification (Sections 2.2.15–2.2.16); Apply at least 60 days before construction (90 days for Locally Exempt projects over 20 acres, discharges within 500 feet of a tidal wetland, or discharges to sediment-impaired waters); Locally Approvable projects of 1 to under 5 acres with written municipal erosion and sediment control approval file no application (Sections 2.5.3, 3.3.2, 3.3.3); Pre-construction meeting with the designing Qualified Professional, the Qualified Inspector, and all contractors, with a signed meeting report kept in the SPCP (Section 5.1.6.1); Signed certification from every contractor and subcontractor kept in the SPCP (Section 5.1.6.2); Weatherproof 2 ft × 3 ft permit sign in English and Spanish, legible from the nearest public road (Section 5.1.7); Two rows of erosion control barriers on slopes of 8% or more; a double row of sediment barriers where disturbance is within 50 feet upgradient of a wetland or water (Sections 5.2.2.1.b and 5.2.2.5); Phase work to avoid disturbing more than five acres at one time wherever practicable (Section 5.2.1.2.b); Dewatering turbidity monitoring, reported to DEEP monthly (Sections 5.2.2.8 and 5.3.2.2); Post-construction, final stabilization (Qualified Professional Engineer), and termination inspections before the Notice of Termination; the termination inspection follows at least one year of maintained final stabilization (Sections 5.2.4.3–5.2.4.5).

What the plan must contain

A Connecticut SPCPis 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 SPCP is signed by the legally responsible party before work begins.

Required and conditional BMPs

Filing your Notice of Intent

File the application, SPCP, and certifications electronically through DEEP’s ezFile portal (Sections 3.3 and 3.9); report changes by Notice of Change to DEEP.StormwaterConstruction@ct.gov before implementing them (Section 3.5).

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

Inspection requirements

Inspect at least once every calendar week and within 24 hours of the end of a storm that generates a discharge (for storms ending on a weekend, holiday, or other time after which normal working hours will not begin within 24 hours, the 24-hour inspection applies only to storms of 0.5 inch or more; after smaller storms, inspect at the start of the next normal working hours; a Qualified Inspector inspects, with a rain gauge maintained on site) (CTR100000 Section 5.2.4.2.a). Temporarily stabilized areas are inspected at least weekly until final stabilization, and at least monthly once final stabilization is achieved (CTR100000 Section 5.2.4.2.a); each construction phase also gets plan implementation inspections at least once within the first 30 days and at least three times, 7 or more days apart, within the first 90 days (CTR100000 Section 5.2.4.1). Every inspection is dated and signed, and any failed control is corrected before the next storm.

How Connecticut differs from the federal permit

Because Connecticut 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