Maine
The stormwater permit for construction in Maine
Maine 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
Maine Construction General Permit (MCGP)
- Issued by
- Maine Department of Environmental Protection (Maine DEP), Bureau of Land Resources
- Version determined against
- as published by the state agency
- Effective
- 2025-01-14
- Expires
- 2030-01-13
Who may prepare the plan
A credentialed preparer is requiredMaine 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
- Maine DEP certification in erosion control practices (or an equivalent certification accepted by the Department)
No acreage threshold gates this requirement — Part III.A applies it to any covered construction activity (1+ acre disturbed, or part of a common plan of development/sale ultimately disturbing 1+ acre), not just 'large construction activity' (5+ acres, which only adds Appendix D SWPPP content requirements). Confirmed no PE stamp/seal requirement anywhere in the permit: a full-text search of the permit body found zero occurrences of 'professional engineer,' 'P.E.,' 'licensed engineer,' 'seal,' or 'stamp.' A separately Department-certified Resident Inspector is also required (Part II.Q).
Does a site in Maine 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 Maine Construction General Permit (MCGP), 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.
- Maine's MCGP is a rule-issued general permit (06-096 CMR Chapter 529) under Maine's own delegated NPDES program (MEPDES); it carries no discrete permit-tracking number -- identified only by title and effective date (January 14, 2025). No numeric turbidity/pH/TSS benchmark was found; Maine's program is BMP/design-standard based. The main permit body cross-references Appendix A(4)/(6) for stabilization deadlines, but the fetched Appendix A text numbers these differently (item 9 and item 11) -- the content actually read was used rather than the possibly-mismatched cross-reference numbers. Could not verify any increased-frequency-near-sensitive-waters rule beyond TMDL consistency, or any arid/drought reduced-frequency provision (inapplicable to Maine's climate).
- Maine 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
Maine. The state runs its own programme, issued as an unnumbered or rule-based general permit rather than under a discrete permit number.
- 3
Preparer credential
Maine 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.
VerifiedMaine Construction General Permit (eff. Jan 14, 2025), Part III (Requirements), Section B (SWPPP), para. 3: "The Stormwater Pollution Prevention Plan must be prepared by a professional who has a valid Department certification in erosion control practices, or an equivalent certification accepted by the Department."Source
What to do next
- 1. Confirm the governing permit. Read Maine Construction General Permit (MCGP) directly. It is linked above, and it is the document an inspector will hold you to. Maine Department of Environmental Protection (Maine DEP), Bureau of Land Resources
- 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 Maine
- 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 Maine
Screen a Maine site now
Runs in your browser. Nothing about the site is transmitted.
What people ask about the Maine construction stormwater permit
Do I need a stormwater permit for a construction site in Maine?
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 Maine?
Maine Department of Environmental Protection (Maine DEP), Bureau of Land Resources issues Maine Construction General Permit (MCGP).
Does Maine require a qualified preparer for the plan?
Maine 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 Maine will ask you for
The screening is free. Holding the written plan and the retained inspection log is what the permit actually demands.