Cape Cod Septic Guide

Designated 2023-07-07

Harwich

Harwich sits across five watersheds in MassDEP's application table — three areas on the address map, since Allen, Wychmere and Saquatucket Harbors are drawn as one. It holds an unusual position: four are covered by Notices of Intent, while Pleasant Bay is covered by a Watershed Permit that has actually been granted — permit 01-M1, running to 2046.

What Harwich filed

WatershedFilingTransmittalMassDEP's map calls it
Herring River Notice of Intent 24-WP94-0007-APP Herring River Embayment System
Pleasant Bay Permit granted Permit 01-M1 Pleasant Bay System
Wychmere Harbor Notice of Intent 24-WP94-0006-APP Allen, Wychmere and Saquatucket Harbors Embayment Systems
Saquatucket Harbor Notice of Intent 24-WP94-0005-APP Allen, Wychmere and Saquatucket Harbors Embayment Systems
Allen Harbor Notice of Intent 24-WP94-0004-APP Allen, Wychmere and Saquatucket Harbors Embayment Systems

MassDEP's address map draws these 5 rows as 3 areas — it groups some of them and uses longer names. Match on the opening words.

What that means if you are selling

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

Start from the map, not from this table. Look the address up on MassDEP's address map, read the Estuarine System Name in the popup, and put that name into the check tool. If the map shows no shaded area at the property, box 4 applies.

If Harwich 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.

Pleasant Bay is different. The permit in force is 01-M1, issued 10 February 2026 and running to 10 February 2046 — a granted permit, not an application, and dated well beyond the five-year clock above. MassDEP’s watershed application table dated 11 June 2026 still lists the superseded permit 001-0. The permit in force is 01-M1. If a Board of Health quotes 001-0 from that table, both refer to the same permit for the same four towns.

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), Dennis (Notice of Intent)
  • Pleasant Bay — also Brewster (Permit granted), Chatham (Permit granted), Orleans (Permit granted)

A property sitting near a watershed boundary can return two names from a single click on MassDEP's map, each a real watershed. Run the check once for each. If the two give different answers, Harwich Board of Health decides which one the property is in.

The requirement that applies either way

A passing Title 5 inspection is required before you transfer title in Massachusetts. For an ordinary sale it must be done at or within two years before the transfer — or up to three years before, if the report comes with pumping records showing the system was pumped at least once a year since (310 CMR 15.301(1)). Some transfers run on their own timetables under 15.301(3), and refinancing or adding a spouse is not a transfer at all under 15.301(2). That is independent of anything on this page.

Your septic records

Harwich 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. Map names transcribed from MassDEP's NSA Address Lookup Map, 10 August 2026.

Get a Title 5 inspection quote

Tell us the property and what you need. We pass the request to licensed Title 5 system inspectors covering Harwich.