The Cumberland and Oxford Canal was opened in 1832 to connect the largest lakes of southern Maine with the seaport of Portland, Maine. The canal followed the Presumpscot River from Sebago Lake through the towns of Standish, Windham, Gorham, and Westbrook. The Canal diverged from the river at Westbrook to reach the navigable Fore River estuary and Portland Harbor. The canal required 27 locks to reach Sebago Lake at an elevation of above sea level. One additional lock was constructed in the Songo River to provide of additional elevation to reach Long Lake from Sebago Lake. Total navigable distance was approximately from Portland to Harrison at the north end of Long Lake. A proposed extension from Harrison to Bear Pond and Tom Pond in Waterford would have required three more locks on the Bear River, but they were never built. A state lottery was authorized to help raise $50,000 for the project, and the Canal Bank of Portland was chartered in 1825. The canal was completed in 1830 at a cost of $206,000. The excavated portions of the canal had a surface width of with a wide channel deep. The locks were wide and long. Lock walls were made of granitemasonry with wooden gates at either end. A lock keeper was stationed at each lock to move the lock gates with heavy timber balance beams, manipulate iron valves to adjust water levels within the lock, and collect a 6 cent fee for use of the lock.
Canal boats
The flat-bottomed canal boats had blunt bows, square sterns, and a draft of. A tow path adjacent to the excavated portions of the canal enabled horses to tow the canal boats while the boatmen steered with poles. Canal boats using the lakes had a removable keel and two short hinged masts capable of supporting sails or being folded down for passage through the excavated canal. Cargos included lumber, masts, barrel hoops and staves, boxmaking shook, and firewood from the interior to Portland. Apples were an important agricultural product of the area; and Oriental Powder Company mills adjacent to the canal in Windham manufactured nearly 25% of the Union gunpowder supply for the American Civil War. Canal boat passengers were charged one-half cent per mile. A wide variety of manufactured goods moved inland through the canal from Portland. The south end of Long Lake is locally known as Brandy Pond because a barrel of brandy was lost from a canal boat during passage through that part of the waterway.