Dock, pier and float rules in Portland, Maine
Possibly, with permits. Portland's shoreland rules allow one pier, dock or wharf per lot outside the working-waterfront zones. It must be no bigger than needed and needs no water setback. A new permanent structure over the water also needs a Maine DEP permit and may need Army Corps of Engineers and Portland Harbor Commission approval. We didn't have the Harbor Commission's rules, so mooring and harbor-channel requirements aren't covered here.
| Number per lot | One pier, dock, wharf or similar structure (except in the WCZ, EWPZ and WPDZ waterfront zones) [1] |
| Seasonal vs. permanent | Temporary = in or over the water less than 7 months in any 12; permanent = 7 months or more [2] |
| Size | No larger than necessary to carry on the activity [3] |
| Water setback | None required for piers, docks and retaining walls [4] |
| State/federal permits | DEP NRPA permit for new permanent structures over water; Army Corps and Board of Harbor Commissioners permits may be needed in navigable waters [5] |
| Permanent docks on non-tidal water | Only if a temporary dock isn't feasible and DEP has issued a permit [6] |
| Buildings on a pier | Only if they need direct water access; max 20 ft above the pier (outside waterfront zones) [7] |
| Structures on floats | Prohibited unless designed and registered as a watercraft [8] |
Town rules (Shoreland Overlay Zone)
Section 11.4.2 of the Land Use Code covers piers, docks, wharves and other structures extending over or below the high-water line. It sorts them by how long they stay in the water: temporary means in or over the water for less than seven months in any 12-month period, and permanent means 7 months or more [2]. Outside the working-waterfront zones (WCZ, EWPZ and WPDZ), a single lot may have no more than one pier, dock, wharf or similar structure below the high-water line [1]. Access from shore must be on suitable soils and built to control erosion. The facility must not interfere with beaches, must minimize harm to fisheries, and must be no larger than necessary for the activity, consistent with the surrounding character and uses [3]. Piers, docks, retaining walls and other structures that need direct access to the water don't have to meet the 75-foot shoreland setback [4].
State, federal and harbor approvals
New permanent structures, and expansions of them, projecting into or over the water need a DEP permit under the Natural Resources Protection Act. Permits may also be required from the Army Corps of Engineers and the Board of Harbor Commissioners in navigable waters [5]. On non-tidal waters, a new permanent pier or dock isn't allowed unless a temporary one isn't feasible and DEP has issued a permit [6].
What you can't put on a dock
New buildings on or next to a pier or dock are allowed only if they need direct water access as an operational necessity, and can be no more than 20 feet above the pier [7]. This limit doesn't apply in the waterfront and I-B zones. A structure built on floats is prohibited unless it is designed as, and registered with Inland Fisheries & Wildlife as, a watercraft [8]. Existing structures on piers can't be converted to dwelling units.
Missing source
The Portland Harbor Commission's rules govern moorings and pier buffers from navigation channels in Portland Harbor. We couldn't obtain them, so this page doesn't cover mooring permits or channel setbacks.
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Next steps
- Confirm your lot is in the Shoreland Overlay Zone and doesn't already have a pier or dock.
- Apply to Permitting & Inspections (207-874-8703) for a building/site plan permit with a surveyed, scaled plan showing the dock size and location.
- For a permanent dock (in the water 7+ months a year), apply to Maine DEP for an NRPA permit and check with the Army Corps of Engineers.
- In Portland Harbor or other navigable waters, contact the Portland Harbor Commission/harbormaster about Harbor Commission approval, moorings and channel buffers.
Common questions
- Can I build a dock in Portland, Maine?
- Possibly, with permits. Portland's shoreland rules allow one pier, dock or wharf per lot outside the working-waterfront zones (WCZ, EWPZ and WPDZ). It must be no larger than necessary.
- Do I need a state permit for a dock in Portland, Maine?
- A new permanent structure over the water needs a Maine DEP permit under the Natural Resources Protection Act. The Army Corps of Engineers and the Board of Harbor Commissioners may also need to approve it in navigable waters.
- What counts as a seasonal dock in Portland, Maine?
- A temporary structure is in or over the water less than 7 months in any 12. Permanent means 7 months or more.
- Does a dock in Portland, Maine have to meet the shoreland setback?
- No. Piers, docks, retaining walls and other structures that need direct water access don't have to meet the 75-foot shoreland setback.
- Does Portland, Maine's dock guide cover moorings?
- No. Mooring permits and harbor-channel setbacks are governed by the Portland Harbor Commission's rules, which the page couldn't obtain, so they aren't covered.
State and federal rules for docks and piers
DEP permit (Natural Resources Protection Act): Building, repairing or altering a permanent structure in, on or over a great pond, river, stream or coastal wetland needs a DEP permit. "Permanent" means the structure stays in place more than 7 months in any 12-month period. A seasonal dock that comes out each year generally isn't a permanent structure.
State shoreland minimums (your town's ordinance applies these):
- Only one pier, dock or wharf per lot, unless the lot has at least twice the minimum shore frontage.
- A temporary, non-commercial dock on fresh water can be no wider than 6 ft.
- A new permanent dock on fresh water is allowed only if a temporary dock isn't feasible and DEP has issued a permit.
- No living space on or attached to a dock.
State-owned bottom: Below the low-water mark in tidal waters and in great ponds, the bottom belongs to the state. Permanent structures of any size, and large temporary ones, need a lease or easement from the Bureau of Parks and Lands. Non-permanent structures under 500 sq ft don't need one.
Federal and harbor rules: In tidal waters, docks and floats also need U.S. Army Corps of Engineers approval. Moorings are handled by your town's harbormaster under local ordinance (38 M.R.S. §7).
What the ordinance says
- Sec. 11.4.2(B), Land Use Code (Code of Ordinances Chapter 14, ReCode), p. 225
B. No more than one pier, dock, wharf or similar structure extending or located below the normal high-water line of a water body is allowed on a single lot, with the exception that this provision shall not apply in the WCZ, EWPZ, and WPDZ.
- Sec. 11.4.2(A), Land Use Code (Code of Ordinances Chapter 14, ReCode), p. 225
A. For the purposes of this subsection, temporary shall mean structures which remain in or over the water for less than seven months in any period of 12 consecutive months and permanent shall mean structures which remain in or over the water for 7 months or more in any period of 12 consecutive months.
- Sec. 11.4.2(F), Land Use Code (Code of Ordinances Chapter 14, ReCode), p. 225
F. The facility shall be no larger in dimension than necessary to carry on the activity
- Sec. 11.4.1(A)(3), Land Use Code (Code of Ordinances Chapter 14, ReCode), p. 224
No setback shall be required for piers, docks, retaining walls, or any other structures which require direct access to the water
- Sec. 11.4.2(G), Land Use Code (Code of Ordinances Chapter 14, ReCode), p. 225
G. New permanent structures, and expansions thereof, projecting into or over water bodies shall require a permit from the Department of Environmental Protection pursuant to the National Resources Protection Act, 38 M.R.S. § 480-C. Permits may also be required from the Army Corps of Engineers and Board of Harbor Commissioners if located in navigable waters.
- Sec. 11.4.2(H), Land Use Code (Code of Ordinances Chapter 14, ReCode), p. 225
H. New permanent piers and docks on non-tidal waters shall not be permitted unless it is clearly demonstrated to the review authority that a temporary pier or dock is not feasible, and a permit has been obtained from the Department of Environmental Protection, pursuant to the Natural Resources Protection Act.
- Sec. 11.4.2(I), Land Use Code (Code of Ordinances Chapter 14, ReCode), p. 225
Where such a structure is permitted under this subsection, such structures shall not exceed 20 feet in height above the pier, wharf, dock, or other structure.
- Sec. 11.4.2(J), Land Use Code (Code of Ordinances Chapter 14, ReCode), p. 225
J. A structure constructed on a float or floats is prohibited unless it is designed to function as, and is registered with the Maine Department of Inland Fisheries and Wildlife as, a watercraft.