A plan to build a two-story commercial building on a wetland at the edge of the Lagoon Pond in the Tisbury Marketplace is still in the early stages, but so far it has not found much favor from the Martha’s Vineyard Commission.

Sam Dunn, the developer of the marketplace some 20 years ago, wants to build a 7,050-square-foot building with three retail units, two offices, one apartment, and one marine-related unit on the grassy area that abuts Lagoon Pond.

The building would be located approximately 50 feet from the edge of the pond, inside the 100-foot wetlands buffer and flood plain.

The plan is in front of the commission as a development of regional impact (DRI); the commission’s land use planning subcommittee began a pre-public hearing review on Jan. 25.

Mr. Dunn has said the marine unit might be a space for a chandlery, sailing school or boat builder. The location falls within two town special zoning districts: the commercial management zone and waterside management area, which is supposed to be for marine-related uses only.

The marketplace is a commercial complex off Beach Road that includes a fish market, toy store, pizza shop, architect’s office and restaurant. Mr. Dunn has retained development rights to the remaining green space in the complex. The marketplace complex is connected to the town sewer.

The complex has expanded slowly over the years; in 1990 a second lot was allowed, which is currently a rental car parking lot next to Saltwater restaurant.

In 1997 an outside deck was added to the pizza shop, and in 2001 the complex switched from a septic system to the town sewer. In 2007 the building that now houses Saltwater expanded from a small bakery and coffee bar to a restaurant with an additional 500 square feet. Last year Mr. Dunn, current owner of Saltwater, enclosed the restaurant’s screened porch.

Minutes of the land use planning committee meeting from last month show that Tisbury conservation commission member John Best questioned the wisdom of putting a building so close to the pond. “There are times when you allow activities within 100 feet of water, but mainly if there is no alternative,” Mr. Best said, according to the minutes.

He also questioned the need. “I can’t foresee a need for water-related uses on the Lagoon side. It is an active shellfishing area. We would not allow a pier there . . . it is very shallow,” he said.

Minutes show that commissioner Chris Murphy praised Mr. Dunn for making improvements to the shopping complex over the years, but recalled Mr. Dunn making assurances 20 years ago he would not develop the Lagoon-side part of the property.

“The Tisbury Marketplace was a disaster before Mr. Dunn took over. It had all kinds of businesses that were scattered about haphazardly. Mr. Dunn has done a good job and we give him points for that . . . I have no problem with new buildings, but not this location,” Mr. Murphy said, adding: “Going into a protected zone is a big mistake. He should stay on the other side of the fence.”

The land use planning committee will discuss the plan again on Feb. 22.