PROVIDENCE, R.I. (AP) — An offshore wind developer is mapping the seafloor off southern New England to design two new wind farms.

Providence-based Deepwater Wind said Friday it's deploying a survey vessel and two dozen experts next week from Rhode Island to begin surveying its federal lease site.

The company plans to build a wind farm there to supply power to Rhode Island and Connecticut and another wind farm for Long Island, New York.

Deepwater Wind says the five-month effort will influence the turbines' design and location. It's looking for buried boulders and measuring the seafloor's depth and slope.

The 256-square-mile area is roughly midway between Block Island, Rhode Island and Martha's Vineyard, Massachusetts.

Deepwater Wind is planning a third wind farm near Maryland. It built the first U.S. offshore wind farm off Block Island.