Designated 2023-07-07

Dennis

Dennis has filed Notices of Intent on three watersheds, two of which it shares with neighbouring towns that took different routes.

What Dennis filed

What that means if you are selling

Every watershed in Dennis is covered by a filing, so the nitrogen upgrade requirement is suspended here. On the MassDEP disclosure form a seller in one of these watersheds would normally tick box 2 — in a Nitrogen Sensitive Area, not currently subject to an upgrade — and name the filing above.

If Dennis were to miss the milestones in its approved schedule, MassDEP could start the five-year upgrade clock, which would run to 8 July 2030. That has not happened. It is the reason this page carries a date and gets re-checked.

Watersheds shared with other towns

These cross town lines, and the neighbouring town did not always file the same way — so two properties in the same watershed can sit in different positions.

• Herring River — also Brewster (Permit application), Harwich (Notice of Intent)
• Swan Pond River — also Brewster (De Minimis application)
• Bass River — also Brewster (De Minimis application), Yarmouth (Notice of Intent)

The requirement that applies either way

A passing Title 5 inspection is required before you transfer title anywhere in Massachusetts, and it is valid for two years — three if you have documented annual pumping. That is independent of anything on this page.

Your septic records

Dennis Board of Health holds septic records and Title 5 reports. If you are trying to establish that nitrogen-reducing technology was already installed — box 3 on the disclosure form — that installation date is what you need, and the Board of Health file is where it lives.

Filings from MassDEP watershed application table, 11 June 2026.