Connecticut
The stormwater permit for construction in Connecticut
Connecticut runs its own NPDES programme, so a state issued construction general permit governs. Below is what our engine can say about it, and where we have not read that permit, what it will not say.
Governing permit
NPDES General Permit for the Discharge of Stormwater from Construction Activities, Permit No. CTR100000
- Issued by
- Connecticut Department of Energy and Environmental Protection (CT DEEP)
- Permit number
- CTR100000
- Version determined against
- as published by the state agency
- Effective
- 2026-01-01
- Expires
- 2030-12-31
Who may prepare the plan
A credentialed preparer is requiredConnecticut requires a credentialed preparer. Treat the generated document as a complete draft for that person to review, adopt and sign. It is not by itself a compliant filed plan.
Qualifying routes
- Connecticut-licensed PE
- Connecticut-licensed landscape architect
An independent reviewer is also required, and at 20 acres or more that reviewer must be from a different firm.
Does a site in Connecticut need coverage
Worked for a one acre site as a reference point. Change the acreage in the tool below and the answer, and its reasoning, change with it.
Coverage
Permit coverage required
The project disturbs 1 acres, at or above the 1 acre threshold, so it needs permit coverage.
Determined against dataset version 2026-07-19.
Read these before you act on the answer
- Requirements below are what we have read and cited directly from NPDES General Permit for the Discharge of Stormwater from Construction Activities, Permit No. CTR100000, not the federal CGP. A category we have not yet transcribed from this permit is omitted here rather than assumed to match EPA's rule.
- CT's permit sets no numeric turbidity/effluent benchmark value for construction runoff; it only references federal ELG (40 CFR 450) generically, so no numericLimitsAndBenchmarks entry is included. CT does not use an acreage-tiered stabilization-completion deadline like federal Table 2 (its rule is a flat 7-day timer). The permit does not use the term NOI -- coverage is via a reviewed 'Application' with a 60/90-day pre-commencement lead time, and the standard NOT deadline is not a fixed day-count (triggered by completion milestones including 1 year of maintained final stabilization) except for the narrow Change-of-Permittee case (30 days).
- Connecticut requires a credentialed preparer. Treat the generated document as a complete draft for that person to review, adopt and sign. It is not by itself a compliant filed plan.
- Basinwise does not perform the physical site inspections the permit requires. Those must be carried out on site by a qualified person.
How this answer was reached, step by step
- 1
Coverage threshold
The project disturbs 1 acres, at or above the 1 acre threshold, so it needs permit coverage.
- 2
Permitting authority
Connecticut. The state runs its own programme under CTR100000.
- 3
Preparer credential
Connecticut requires a credentialed preparer. Treat the generated document as a complete draft for that person to review, adopt and sign. It is not by itself a compliant filed plan.
What to do next
- 1. Confirm the governing permit. Read NPDES General Permit for the Discharge of Stormwater from Construction Activities, Permit No. CTR100000 directly. It is linked above, and it is the document an inspector will hold you to. Connecticut Department of Energy and Environmental Protection (CT DEEP)
- 2. Settle the preparer question before you draft. Getting this wrong costs a redraft at best. The detail is on the credential page for this state. Preparer credential in Connecticut
- 3. Screen the site. Run the real acreage and receiving water facts through the tool below. You get the inspection frequency, the stabilisation deadlines and the filing path with the permit section behind each.
- 4. Read the requirements in full. SWPPP requirements in Connecticut
Screen a Connecticut site now
Runs in your browser. Nothing about the site is transmitted.
What people ask about the Connecticut construction stormwater permit
Do I need a stormwater permit for a construction site in Connecticut?
Permit coverage is triggered at one acre of land disturbance, and below one acre if the project is part of a larger common plan of development or sale that will ultimately disturb an acre or more. The project disturbs 1 acres, at or above the 1 acre threshold, so it needs permit coverage.
Who issues the construction stormwater permit in Connecticut?
Connecticut Department of Energy and Environmental Protection (CT DEEP) issues NPDES General Permit for the Discharge of Stormwater from Construction Activities, Permit No. CTR100000.
Does Connecticut require a qualified preparer for the plan?
Connecticut requires a credentialed preparer. Treat the generated document as a complete draft for that person to review, adopt and sign. It is not by itself a compliant filed plan.
Keep the record Connecticut will ask you for
The screening is free. Holding the written plan and the retained inspection log is what the permit actually demands.