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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
Read the permitConnecticut Department of Energy and Environmental Protection (CT DEEP)

Who may prepare the plan

A credentialed preparer is required

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.

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.

Verified2026 Connecticut CGP sections 2.2.14 and 2.2.16Source

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

Verified

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

  • We have identified NPDES General Permit for the Discharge of Stormwater from Construction Activities, Permit No. CTR100000 as the governing permit but have not loaded its requirements. The requirements below are not shown because we will not substitute the federal permit's rules for a state's. Confirm with Connecticut Department of Energy and Environmental Protection (CT DEEP).
  • 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. 1

    Coverage threshold

    The project disturbs 1 acres, at or above the 1 acre threshold, so it needs permit coverage.

    VerifiedPart 1.1.2Source
  2. 2

    Permitting authority

    Connecticut. The state runs its own programme under CTR100000.

  3. 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.

    Verified2026 Connecticut CGP sections 2.2.14 and 2.2.16Source

What to do next

  1. 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. 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. 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. 4. Read the requirements in full. SWPPP requirements in Connecticut

Screen a Connecticut site now

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Screen your site

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Total land disturbance over the whole project, including staging and access. This decides whether you need a permit at all.

Optional. If you phase the work, the most that will be disturbed at once. Leave blank if the whole site is open together. The stabilisation deadline turns on this figure, not the total.

A half acre lot inside a 40 acre subdivision is covered even though the lot alone is under the threshold. This is the most commonly missed trigger in the permit.

Receiving water and site conditions(optional, but they change the inspection frequency)

May allow a reduced inspection frequency during the seasonally dry period.

EPA keeps permitting authority in Indian country even inside a state that runs its own programme.

No account, no card, nothing 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.

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