PORTLAND, Maine (AP) A Maine science institute said Monday it has reached an agreement to buy a Portland wharf in a move that will preserve working waterfront access in the state’s largest city.

Union Wharf dates to the late 18th century. Gulf of Maine Research Institute said it has signed a purchase and sale agreement with Charlie and Malcolm Poole, who are fifth-generation owners and managers of the wharf.

The two sides did not disclose a purchase price or terms of the agreement on Monday. A spokesperson for the Poole family said the family choose the research institute because of its plan to serve as a steward for the wharf, which is a key piece of the city waterfront.

Maine Department of Marine Resources Commissioner Patrick Keliher said the purchase is good news for Maine marine industries because of growing development pressure.