Stormwater Management: Boston vs Chelsea
How do stormwater management rules compare between Boston, MA and Chelsea, MA?
Boston and Chelsea have similar restriction levels.
Boston, MA
Suffolk County
Boston requires stormwater management plans for any land disturbance over 1 acre under the city's Stormwater Management Ordinance and the EPA MS4 permit. The Boston Water and Sewer Commission (BWSC) administers stormwater utilities and requires on-site retention for new development. Projects must comply with MassDEP Stormwater Management Standards.
View full Boston rules →Chelsea, MA
Suffolk County
Suffolk County municipalities operate under EPA MS4 Phase II permits requiring stormwater management plans for projects disturbing 1+ acre. Boston Water and Sewer Commission enforces stormwater standards under Boston Code Chapter XIV. Chelsea, Revere, and Winthrop adopted stormwater bylaws under MGL c. 83, §10 implementing the 2020 MA DEP Stormwater Handbook.
View full Chelsea rules →Key Facts Comparison
| Fact | Boston | Chelsea |
|---|---|---|
| Trigger | Land disturbance over 1 acre | - |
| Administered By | Boston Water & Sewer Commission | - |
| Standards | MassDEP 10 Stormwater Standards | - |
| Fee Basis | Impervious area stormwater utility fee | - |
| LID Incentive | Fee reductions for green infrastructure | - |
| Federal | - | EPA MS4 Phase II permit |
| State Standards | - | 310 CMR 10.05(6)(k) |
| Boston Threshold | - | 5,000 sq ft impervious |
| Chelsea/Revere | - | 1 acre or 10,000 sq ft |
| TSS Removal | - | 80% required |
Highlighted rows indicate differences between cities.
Boston FAQ
Who manages stormwater in Boston?
The Boston Water and Sewer Commission (BWSC) administers stormwater utilities, drainage, and permit requirements. Projects must also comply with MassDEP Stormwater Management Standards and the EPA MS4 permit.
Do I pay a stormwater fee in Boston?
Yes. BWSC charges a stormwater utility fee based on the amount of impervious surface on your property. Installing green infrastructure like rain gardens or permeable pavement can qualify for fee reductions.
Chelsea FAQ
Do I need a stormwater permit for a home addition in Boston?
Only if the addition creates 5,000+ sq ft of impervious surface. Most single-family additions are exempt, but driveways combined with the addition can trigger BWSC review.
Can I discharge my sump pump to the storm drain?
Clean groundwater is generally allowed, but washing machine, foundation dewatering with sediment, and chlorinated pool water are illicit discharges.
Compare other topics
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