Your township can count your basin without asking
Your township can count your basin without asking
2026-09-15 · Pennsylvania · Regulation
What happened. The Pennsylvania Department of Environmental Protection's guidance on municipal stormwater permits, revised 15 April 2026, states plainly that a municipality may site pollution-control facilities on private property and need not have an agreement with the private owner to do it. In a covenanted Pennsylvania subdivision, the private owner is very often the homeowners association.1
Three answers, read together
The guidance is a question-and-answer document for permittees. Three of its answers matter to associations.
On ownership, FAQ 28: "Ownership is not an issue as BMPs can be publicly or privately-owned. A typical option to consider is the modification of existing flood control basins to improve their pollution control capability."1
On private property, FAQ 30, in its entirety: "Can BMPs be located on private property? Yes."
And the one that matters most, FAQ 31: "Are municipalities required to have agreements with private property owners where BMPs will be constructed? No, although permittees may use such agreements to protect their interest. DEP requires agreements between MS4s which are collaborating on individual BMPs or are participating in a joint PRP/TMDL Plan."1
The Department requires an agreement between two municipalities collaborating. It does not require one between a municipality and the private owner whose land is being counted.
Why existing basins are the target
FAQ 28's reference to "existing flood control basins" is not abstract. The detention basins in a Pennsylvania township are overwhelmingly the ones built into 1990s and 2000s residential subdivisions and conveyed to the homeowners association at turnover. Retrofitting an existing basin is cheaper than building a new facility, and DEP says so.
The obligation that follows the credit
This is the mechanism by which a township's permit becomes an association's special assessment. FAQ 76 addresses operation and maintenance:
"The MS4 program requirement in MCM #5, BMP #3 that requires permittees to ensure adequate O&M of PCSM BMPs refers to all PCSM BMPs that were installed to meet requirements in NPDES Permits for Stormwater Discharges Associated with Construction Activities under Chapter 102. This includes both BMPs installed on public property and BMPs installed on and private property."1
And: "all BMPs being used for credit towards the pollutant load reduction obligation of a permittee's PRP or TMDL Plan must be shown to be functioning as designed and being maintained in accordance with their O&M plan. Therefore, if the municipality is going to use non-Chapter 102 BMPs for MS4 credit, those BMPs will also need to be inspected."
Put the pieces together and the chain is complete. A municipality counts the association's basin toward its permit. The basin must then be demonstrated to be functioning as designed and maintained per its operation and maintenance plan. The municipality must inspect it. And if it is not being maintained, the municipality loses the credit — which gives the township a direct and pressing interest in what the association does with a facility the township does not own and has no agreement about.
Where associations get caught
Three specific failures, all common:
- Nobody has the O&M plan. The plan was prepared for the developer's construction permit and handed over, or not handed over, at turnover twenty years ago. A board asked to demonstrate maintenance in accordance with a plan it has never seen is in difficulty immediately. This document should be located before anyone asks for it.
- The basin has been landscaped into something else. Basins get mown as lawn, planted, used for storage, or allowed to grow in. Each of those can mean the facility is not functioning as designed.
- Reserves do not contemplate it. Basin retrofits, outlet-structure replacement and sediment removal are capital events. An association whose reserve study covers roofs, roads and the clubhouse but not the stormwater facility has a gap that shows up as a special assessment.
The other numbers in the document
Worth knowing because they set the municipality's calendar, which sets yours. There is a $500 annual permit instalment due 30 September each year. The annual reporting period runs 1 July to 30 June, with reports due 30 September. So a township's stormwater year closes at the end of September, which is when its attention to basins is highest.
FAQ 69 sets what a municipality must show when it relies on a facility outside its own planning area: it must "indicate that the MS4 jurisdiction holds sufficient legal rights to access the property", and must "include plans for long-term operation and maintenance and annual verification of the BMP(s), and provide for municipal access to the BMP if needed in the future." Access rights and long-term maintenance planning are required there — which is a useful contrast with the absence of any agreement requirement in FAQ 31.
FAQ 77 notes that "The majority of existing county SWMPs are more than five years old", and that an ordinance tied to a stale county watershed plan "is still valid." An association cannot resist a municipal stormwater requirement on the ground that the underlying county plan is out of date.
A board's options
In order: find out whether the association owns a stormwater facility, and which parcel it sits on. Locate the operation and maintenance plan. Ask the township directly whether it is claiming credit for the facility under its permit — a question most boards have never asked and which the township can answer. If the answer is yes, ask to see the inspection regime and negotiate an agreement, because FAQ 31 says the municipality is not required to have one but expressly permits it, and an agreement is where access, inspection frequency, standards and cost-sharing get written down.
An association with no agreement has all of the maintenance obligation and none of the negotiated terms.
What to watch next
The replacement general permit. PAG-13 expired in March 2023 and the programme is running on administrative extension, with DEP stating it does not plan to publish the final permit during 2026. When it does arrive it carries a volume-management requirement and a new calculator, and the obligations it imposes on municipalities will land on the facilities they already have access to — which are, disproportionately, association-owned basins.
Related Pennsylvania HOA Topics
Stay on top of Pennsylvania HOA law
Every week: new Pennsylvania legislation, court rulings, and regulatory developments affecting condos, planned communities, and property managers. Free.
No spam. Unsubscribe anytime.