Off-Grid Living in Dennis, Massachusetts

I'll be upfront: Dennis, Massachusetts is not a place where you can just buy a wooded lot on Cape Cod and quietly disappear off-grid. It's a fully zoned town, and between Town Meeting-adopted zoning bylaws, the Planning Board, the Zoning Board of Appeals, the Building Department, and a notably active Board of Health, there are several layers of local review stacked on top of Massachusetts state code. None of this is a legal opinion, it's what I found digging through the town's own published bylaws and department pages, so treat it as a starting map, not the final word.

Zoning in Dennis runs through Chapter 191 of the town's Zoning Bylaw, administered by the Planning Board and Zoning Board of Appeals. It's a comprehensive, use-district based bylaw, over a hundred pages, covering dimensional requirements, floodplain overlays, and wetlands-adjacent siting tied to the state Wetlands Protection Act. If your land touches wetlands or floodplain, expect an extra layer of scrutiny.

Living in an RV or trailer as your actual dwelling is tightly restricted. Dennis bylaw makes it unlawful to park a trailer or mobile home for habitation anywhere in town for more than about a week, outside a licensed trailer park, without a special permit from the Select Board. If you already owned a trailer on your property before the bylaw existed, you're likely grandfathered in. Dennis has been discussing an Accessory Dwelling Unit bylaw, but I couldn't confirm from official sources whether it's been formally adopted yet, so check with Planning before assuming ADUs are an option.

Building permits run through the Dennis Building Department, and multiple town departments have to sign off before the permit is actually issued. This is a real multi-office process, not a rubber stamp.

Septic is where Dennis gets serious. The Board of Health enforces its own local sewage disposal regulations layered on top of the state's Title 5 code (310 CMR 15.000), and variances are required for construction in environmentally sensitive areas. The town actively pursues enforcement against failing systems. Composting toilets aren't addressed separately in what I found, so ask the Board of Health directly if that's your plan.

Greywater and rainwater harvesting have no Dennis-specific bylaws that I could find, meaning the state's Title 5 baseline (which treats greywater as wastewater) likely applies by default. This is unclear at the local level, so it's worth a direct call to the Board of Health.

Private wells fall under Board of Health jurisdiction, largely through setback and siting rules tied to septic regulations rather than a standalone well bylaw.

Full utility disconnection while occupying a dwelling looks difficult in practice. The town's Housing Space and Use bylaw requires habitable dwellings to be registered and certified by the Health Director under the state Sanitary Code and local zoning bylaws, which effectively ties occupancy to code compliance.

Bottom line: Dennis is workable for off-grid-style building and water systems, but everything routes through Planning, Building, and Board of Health, and you should confirm specifics before you buy land or design a system.