The Tobin Memorial Bridge was erected in 1948-49 and opened to traffic in 1950. It connects the Charlestown section of Boston with Chelsea. The bridge provides three travel lanes northbound on its lower level and three lanes southbound on the upper level. The 36-foot-wide roadway is bounded on both sides by safety walks (2'7" wide) with steel-pipe railings on each side.
Tolls are collected from southbound cars only. As of July 21, 2014 All Electronic Tolling
is in use on the Tobin Bridge.
All Electronic Tolling (AET) is a form of toll collection that allows drivers to pay their toll without stopping or slowing down. AET is safer, quicker, and more convenient for our customers.
The main structure over the Mystic River is a three-span, cantilevered truss 1,525' in length. Its center span is 800' and the maximum truss height is 115'. It provides a navigable waterway opening 700' wide by 135' high. A smaller, simply supported warren truss spans the Little Mystic. It reaches a maximum truss height of 65' and is 439' long. Its navigable waterway opening measures 340' wide by 100' high.
The approaches comprise 36 spans on the north and 32 spans on the south. These spans are built-up plate girders of variable lengths (average length is 100'). On the twelve-span toll plaza--set between the Little and Big Mystic trusses--the roadway widens to102 feet to accommodate seven collection lanes.
Recently rehabilitated, the toll plaza sits on the upper level and incorporates such features as a walkway across its top (for electrical maintenance), new heated and air-conditioned booths, an overhead electronic message board and a fire-suppression system.
A maintenance garage, located in Chelsea, houses all maintenance, operating, and mechanical equipment for upkeep of the bridge. Including north and south approaches, the bridge is approximately 2 1/4 miles long.
Work Wrapping Up On Final Year of Three-Year Project
On Friday morning, November 14, 2014, the lane restrictions in the northbound direction of the Tobin Bridge were removed. Daytime lane restrictions during off-peak hours will occur on an an-needed basis to complete remaining work. On Tuesday morning, October 21st, 2014 the lane restrictions in the southbound direction of the Tobin Bridge were removed. Daytime lane restrictions during off-peak hours will occur on an an-needed basis to complete remaining work.
This is the third year of a three-year, $44.8 million bridge preservation project. MassDOT's contractor is Liberty-Alpha Joint Venture.
Tobin by the Numbers
J.E. Greiner Co.
April 12, 1948
February 27, 1950
2 1/4 miles
Roadway vertical clearance
254' above sea level
85' below sea level
Mystic river span
Clearance above high water mean: 135'
Little Mystic span
Clearance above high water mean: 100'
One-way into Boston (southbound)
One-way out of Boston (northbound)
Weight: 12 tons per axle
Length (single trailer unit): 45'
Length (with trailer): 85'