The Francis Scott Key Bridge carries Interstate 695 over the Patapsco River and Baltimore Harbor in Baltimore and Baltimore County, Maryland. It is the longest bridge in the Baltimore metropolitan area.
In the 1960s, the Maryland State Roads Commission concluded that there was a need for a second Baltimore Harbor crossing after the Baltimore Harbor Thruway & Tunnel opened in 1957. It began planning for a single-tube, two-lane tunnel under the Patapsco River downstream from the Baltimore Harbor Tunnel between Hawkins Point and Sollers Point in the Outer Harbor. 1 8 Plans were also underway for a drawbridge to the south over Curtis Creek to replace an earlier c. 1931 drawbridge carrying Pennington Avenue over the waterway, and for a tunnel under the Harbor for Interstate 95 in the vicinity of Fort McHenry.
The Outer Harbor Crossing and associated approaches were planned as a two-lane freeway with provisions for dualization as traffic counts increased. 1 Contractors took bearings of the outer harbor bottom and ship channel in the spring of 1969 while other crews constructed causeways for the future tunnel portals. The tunnel was advertised for construction in early 1970 and the bids were received on July 30, 1970. Unfortunately, the bids came back substantially higher than engineering estimates which led the Commission to consider alternate plans, which included a conventional four-lane bridge.
The bridge, which was estimated to cost $50 million, represented the best alternative because it allowed for more traffic lanes and lower operating and maintenance costs than a tunnel. 1 8 It was also $15 million less than expensive than the tunnel option. 2 It would also provide a route for vehicles transporting hazardous materials as those vehicle types were prohibited from tunnels. 1
The substructure contract was let in August 1972 to a joint venture between the Balf Company and Savin Brothers, and to Whaling City Dredge & Dock Corp. for the low bid of $19.5 million, which was $1.1 million under the engineer’s estimate. 2 It involved building all the reinforced concrete vertical piers, from the foundations up to the top of the piers. The J. E. Greiner Co. of Baltimore was hired as the prime engineering consultant for the bridge project, as well as the designer of the main piers and the main and auxiliary spans. 2 The approach spans were designed by Singstad, Kehart, November & Hurka of New York City.
The low bid of $30.7 million, 5% above the engineer’s estimate, for the construction of the superstructure was awarded to Pittsburgh-De Moines Steel Co. in October. 3 It involved building all the spans of the bridge across the tops of the piers built in the substructure contract, which included the 2,644-foot-long continuous Warren through truss main span, the plate girder approach spans, and the reinforced concrete roadway deck.
The 11 mile Outer Harbor Crossing project, including a four-lane, 9,091-foot bridge over the Baltimore Harbor, a two-lane, 3,379-foot crossing over Curtis Creek that included a drawbridge, a 3,907-foot, two-lane high-level crossing of Bear Creek, and a viaduct over Bethlehem Steel’s Sparrow Point operations was completed at the cost of $136 million, with the Harbor bridge costing $50.2 million. 1 It opened to traffic on March 23, 1977, and was originally signed as Maryland Route 695 as it did not meet interstate highway standards.
Upon opening, the bridge was named for Francis Scott Key. 6 Historians believed that the bridge passed within 200 feet of the location in the Harbor where Key was detained on a cartel boat when, during the bombardment of Fort McHenry on September 12, 1814, he was inspired to write the words of the song that became the American national anthem. 6 7 8
The Outer Harbor Crossing was widened to four lanes between the MD Route 10 interchange and the western approach to the Baltimore Harbor Bridge, which involved adding a parallel drawbridge over Curtis Creek, between 1980 and 1983. 4 5
Construction to widen the last remaining segment of two lane Outer Harbor Crossing, a 3.6-mile stretch from the eastern approach to the Baltimore Harbor Bridge to MD Route 151, began in 1996. 5 It involved expanding the 3,907-foot Bear Creek Bridge to four lanes, removing the viaduct over the Bethlehem Steel Sparrows Point complex, and reconstructing the MD Route 151 and MD Route 157 interchanges. The project was completed at the cost of $89.5 million on November 6, 1999. 1 4 The widening of the Outer Harbor Crossing to four lanes brought the roadway up to interstate highway standards allowed for the entire Baltimore Beltway to be signed as Interstate 695.
- State: Maryland
- Route: Interstate 695
- Type: Arch, Warren Through Truss
- Status: Active - Automobile
- Total Length: 9,091 feet
- Main Span Length: 1,200 feet
- Deck Width: 58 feet
- Kozel, Scott M. “Francis Scott Key Bridge (Outer Harbor Crossing).” Roads to the Future, 14 Jan. 2006.
- “Substructure under Estimate for Baltimore Harbor Bridge.” Engineering News-Record, 24 Aug. 1972, p. 16.
- “High-level bridge bid near estimate.” Engineering News-Record, 19 Oct. 1972, p. 14.
- Atwood, Liz. “Baltimore Beltway coming full circle.” Baltimore Sun, 6 Nov. 1999, pp. 1A-6A.
- Anderson, Steve. “Baltimore Beltway.” DCRoads.net.
- Rehert, Isaac. “Patapsco Neck people want bridge named for Key.” Baltimore Sun, 8 Apr. 1975, p. B1.
- Hull, Reuben. “Civil Engineering Almanac – Baltimore’s Francis Scott Key Bridge opens.” Civil Engineering Source, 23 Mar. 2021.
- “Francis Scott Key Bridge (I-695).” Maryland Transportation Authority.