Bristol Marine can move forward with its planned expansion after the Bristol Zoning Board unanimously approved a special use permit for the marina project Monday night.

Marina President Andy Tyska plans to add 200 feet, about doubling the length of his current dock, and add 18 boat slips, bringing the total number of slips to 39. The project would allow Bristol Marine to service larger boats in deeper water. Mr. Tyska said he also plans to build a new boat yard shed and install and 8-foot high fence around the Poppasquash Road property to add security and shield work going on in the boatyard from the road.

"This will allow us to expand, grow and create jobs," Tyska told the Zoning Board. He estimated 20 people are currently employed year-round at the marina and related marine businesses on the property, a number that increases to about 26 during the peak spring season.

Before any expansion can begin, Bristol Marine must connect to the town sewer system. There are no access points in the Poppasquash area, forcing Mr. Tyska to run a line to Hope Street at a cost of more than $200,000. The most direct route for the sewer line runs through Colt State Park, requiring approval from the state Department of Environmental Management. After Zoning Board approval Monday — required because Bristol Marine sits in a residential district, having existed before current town zoning laws — the Town of Bristol will partner with Mr. Tyska in applying for DEM approval.

"Getting the sewers is our top priority," Mr. Tyska said, adding he hopes to get state approval for that first phase of the project this summer. The marina's septic system has failed, causing runoff into the bay after every hard rain.

Once the sewer line is in place, Bristol Marine plans to begin construction on the new boatyard shed, followed by the dock expansion. The full project should take about two years to complete, he estimated.

It's been a long time coming to get to this point for Bristol Marina, which initially floated the expansion plans about five years ago. That much larger project — which called for dock expansion north into state waters with as many as 75 boat slips — faced opposition from town officials and neighbors, including the nearby Bristol Yacht Club, which opposed the original plan because it would disrupt the approach path for boats leaving and entering the club. Mr. Tyska said he has worked with those neighbors and scaled down the project to accommodate their concerns. No one spoke against the project Monday.

"This plan truly represents consensus," Mr. Tyska said, noting only about 10-15 customers come and go on most days during peak season; none during the winter. "The impact will be minimal on land and water."

That consensus came at a cost for Bristol Marine. To gain Bristol Yacht Club's agreement, the company has agreed to extend the sewer line to the club, pay to add an additional string of docks to the club, which Bristol Marine will maintain for 10 years, build a keel boat launching pier, and offer a 10 percent discount on marine services to club members. Bristol Marine has also agreed to limit how far east its expansion runs, mitigating the impact on the approach path. Yacht Club members approved the agreement on April 27.

Bristol Marine, despite the expansion, will continue to operate just as it has for several decades, Mr. Tyska said, providing boat storage in the water and on land, as well as service and repairs. Other related businesses on the property include bicycle and kayak rentals, a yacht brokerage firm, marine equipment consignment sales and Legacy Seafood.