The Free- Black bridge was built in 1909 by the Pennsylvania Steel Company of Steelton, Pennsylvania, to replace a former double-decker bridge. It connects Brunswick and Topsham — its structure length is 318 feet and roadway width 12.5 feet. The upper level carries one track of minor branch line of the Maine Central RR that was built between Brunswick and Leeds in 1861. There is also a through girder span at the south end of the upper level truss bridge that was placed in 1957, that carries the railroad over U. S. Route 1 (Mill Street).

This double deck bridge is one of the most unusual and unique bridges in Maine due to its suspended highway deck which runs under the truss of this bridge. The truss also has a deck in the “normal” place for railroad traffic. Structurally, the bridge is essentially a rivet-connected railroad through truss bridge with no unusual details aside from its use of a Warren truss that is subdivided in a manner similar to a Baltimore truss. However, there is one detail on the truss superstructure that is unique which is the bottom chord connections also have pins in them. These pins hold eyebars which in turn connect to pins at the floorbeams under the bridge which hold the unique suspended highway deck.

The lightweight pin-connected nature of the suspended highway deck is a stark contrast to the riveted connections of the truss superstructure. Doubledeck bridges are rare, but what is particularly noteworthy is this use of a pin-connected system for the suspended lower deck, as well as the fact that the lower deck is completely suspended below the truss. More commonly, a double-deck truss bridge either has both decks stacked within the truss superstructure, or it has one deck on top of the truss ( like a deck truss) while the lower deck runs along the bottom chord level like a through truss.

The bridge was closed to the one-lane traffic it served in 2011 following a vehicle collision with some of the suspenders and subsequently deterioration was found in the floor beams and deck surface of the vehicle lane. The vehicle bridge has since been removed.

Information: Bridge Browser and other online sources.