Yes, anyone planning to install or construct a new dock (including other docking structures such as boathouses) within or on the banks of surface waters of New Hampshire must first obtain a wetlands permit. Swim rafts and moorings are not subject to NHDES wetlands permitting, however, they must be installed in accordance with all applicable state laws and rules adopted by the New Hampshire Department of Safety. More information is available on the Department of Safety’s Mooring Program website.

Lakes and ponds over 10 acres in size and navigable rivers are held in trust by the State for the use of the general public. Whenever someone installs a dock in public waters it is being placed in public lands rather than within their own land. The Legislature has charged the NHDES with the responsibility of ensuring that structures are placed in public water in a manner that does not have an unreasonable adverse impact on the interests of the general public. NHDES exercises this responsibility through the application and permitting process.

If you have an existing, legal dock, a wetlands permit is required prior to making any change to the size, location or configuration (footprint) of the docking structure(s). Changing construction materials, such as replacing wood decking with composite decking or replacing a wood seasonal dock with an aluminum seasonal dock, does not require a wetlands permit provided there are no changes to the size, location or configuration (footprint) of the dock; no work is done to any portion of the structure that is located below the water surface at the time of such repair; and no work is conducted in a tidal area.

Existing, legal docks require a wetlands permit for any repairs that result in any changes to the footprint of the dock. Repairs that do not change the size, location or configuration (footprint) of the dock do not require a wetlands permit, provided these repairs are on portions of a dock that are exposed (in "the dry"), and the lake bed is not disturbed.

The below table gives the maximum standard dimensions for docks:

Standard dimensions of docks. Docks must not exceed the dimensions listed in this table.

“Shoreline frontage” means the average of the length of a straight line drawn between the points where the side property lines intersect the reference line and the length of the natural frontage between the same points.

^{The shoreline frontage is the average of the black and blue dotted lines, measured between the property lines.}

Permanent docks, such as piling or crib docks, are permitted only on lakes greater than 1,000 acres in size and only in areas where wind or wave conditions prevent the use of a seasonal dock, based on pre-determined criteria. Seasonal docks are less disturbing on lakes as they are removed during the winter months and do not require the use of aerators for protection against ice damage. The use of aerators disrupts normal lakes cycles and creates dangerously thin ice, a hazard to snowmobilers and ice fisherman.

Permits may be obtained from NHDES to relocate rocks that are navigational hazards. A rock is considered a navigational hazard to the owner if:

• It is within a boatslip or the approach to a docking structure; and
• It is within 3 feet of the water’s surface.

Dredging of sediments can be permitted only in and around existing, legal fixed structures such as boathouses or breakwaters which cannot be easily modified to attain necessary water depths for docking.

A boat slip is a predetermined, waterbody-dependent, volume of water. For waterbodies 10,000 acres or less, a boat slip is a volume of water 20 feet long, 6 feet wide, and 3 feet deep. For waterbodies greater than 10,000 acres, a boat slip is a volume of water 25 feet long, 8 feet wide and 3 feet deep. Note that only one lake in New Hampshire is greater than 10,000 acres: Lake Winnipesaukee. State rules allow for up to two feet of navigation space around a boat slip. Water depth is measured at the normal high water mark (Figure 2).

Yes, a wetlands permit is required to install all boat lifts and jet ski lifts, whether seasonal boat or permanent. One boat lift or jet ski lift is equivalent to a single boat slip.