Last Updated 08/19/2026
EXCERPT- Maine DEP Chapter 500 Stormwater Management Rules
Chapter 500 Stormwater Management APPENDIX B. Inspection and maintenance
2. Post-construction
The following standards must be met after construction.
(a) Plan. Carry out an approved inspection and maintenance plan that is consistent with the minimum requirements of this section. The plan must address inspection and maintenance of the project’s permanent erosion control measures and stormwater management system. This plan may be combined with the plan listed in Section 2(a) of this appendix. See Section 7(C)(2) for submission requirements.
(b) Inspection and maintenance. All measures must be maintained in effective operating condition. A person with knowledge of erosion and stormwater control, including the standards and conditions in the permit, shall conduct the inspections. The following areas, facilities, and measures must be inspected and identified deficiencies must be corrected. Areas, facilities, and measures other than those listed below may also require inspection on a specific site. Inspection or maintenance tasks other than those discussed below must be included in the maintenance plan developed for a specific site.
Every year, the DEP notifies permittees whose projects are up for recertification and educates the property owners, facilities managers, homeowners’ associations as they respond to the recertification inquiries. You can help the DEP to make sure that well-maintained stormwater treatment systems keep the pollutants away from our waters:
- If you have a DEP Stormwater or Site Law permit issued in or after 2006: Please make sure the approved stormwater management inspection and maintenance plan is followed. Inspect your stormwater system and submit the five-year recertification paperwork.
- If you plan on purchasing a property with existing development: The property may already have a DEP Stormwater or Site Law permit. If so, make sure that the seller maintained and recertified the stormwater management system per the permit conditions. You will also need to apply for a permit transfer and assume the inspection and maintenance requirements.
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Frequently Asked Questions
What stormwater regulations apply to properties in Maine?
Maine operates under the National Pollutant Discharge Elimination System, authorized by the U.S. Environmental Protection Agency through state regulation 38 M.R.S.A. § 420-D. The Maine Department of Environmental Protection manages permitting and compliance for stormwater discharge statewide.
How often do Maine stormwater systems need to be recertified?
The Department of Environmental Protection requires recertification of stormwater management systems every five years from the date a property’s permit was issued. The department notifies permittees each year as their projects come up for recertification.
What does the Chapter 500 inspection and maintenance plan require after construction?
Property owners must carry out an approved inspection and maintenance plan covering the project’s permanent erosion control measures and stormwater management system. All measures must be kept in effective operating condition, and inspections must be conducted by someone with knowledge of erosion and stormwater control standards. Any deficiencies identified during inspection must be corrected.
What should a property owner do if their stormwater permit was issued in or after 2006?
Property owners with a Department of Environmental Protection stormwater or site law permit issued in or after 2006 need to follow their approved inspection and maintenance plan, inspect their stormwater system regularly, and submit the five-year recertification paperwork on schedule.
What stormwater obligations come with buying a property that has existing development in Maine?
If the property already has a Department of Environmental Protection stormwater or site law permit, buyers should confirm the seller maintained and recertified the system according to the permit’s conditions. Buyers also need to apply for a permit transfer and take on the inspection and maintenance requirements going forward.
The information on this page is provided for general informational purposes only and is not legal advice. Regulations change frequently — AQUALIS makes no warranty as to the accuracy or completeness of this content, and any reliance on it is at your own risk. Consult a qualified professional or your local regulatory authority to confirm requirements applicable to your specific property.
