Rating:
1 vote

Summer Street over Fort Point Channel Bridge

Photos 

Summer Street Bridge. Draw Span Moves Toward Viewer On Tracks Visible At Center Of Photograph

Photo taken for the Historic American Engineering Record

View photos at Library of Congress

BH Photo #228198

Map 

Street View 

Description 

The Summer St. bridge is a rare movable type of bridge known as a retractile draw, in which the moving span is pulled diagonally away from the navigable channel on several sets of rails. Only four of these have been identified in the country, two of which are on Summer St. in Boston. The form is thought to have been invented by T. Willis Pratt in the 1860's. This bridge is a double retractile: parallel spans pull away from the center in opposite directions. Despite its deteriorating condition, the bridge is the center element of the rich Fort Point Channel Bridge District. / The Summer Street Retractile Bridge is the only known surviving electrically-operated, paired-leaf oblique retractile drawbridge. Despite its poor condition and loss of much of its operating equipment and auxiliary structures (gates, Tender's House, and pedestrian waiting shelters), several of the early components (superstructure, retractile rails, wheels, and operating machinery on the south side) remain. The Summer Street Retractile Bridge is one of five surviving movable bridges located in the proposed Fort Point Channel Historic District. It is one of eight known remaining nineteenth-century movable bridges in the Massachusetts Highway Department Historic Bridge Survey.

-- Historic American Engineering Record

Facts 

Overview
Retractile deck plate girder bridge over Fort Point Channel on Summer Street
Location
Boston, Suffolk County, Massachusetts
Status
Open to traffic
History
Built 1899, Rehabilitated 1918, 1952, 1959, 1967, 1990, and 1998.
Builder
- Berlin Iron Bridge Co. of East Berlin, Connecticut
Design
Rectractable
Dimensions
Length of largest span: 89.6 ft.
Total length: 502.0 ft.
Deck width: 32.2 ft.
Recognition
Eligible for the National Register of Historic Places
Approximate latitude, longitude
+42.35092, -71.05174   (decimal degrees)
42°21'03" N, 71°03'06" W   (degrees°minutes'seconds")
Approximate UTM coordinates
19/331013/4690778 (zone/easting/northing)
Quadrangle map:
Boston South
Inventory numbers
MA B16031 (Massachusetts bridge number)
BH 49469 (Bridgehunter.com ID)
Inspection (as of 08/2014)
Deck condition rating: Satisfactory (6 out of 9)
Superstructure condition rating: Good (7 out of 9)
Substructure condition rating: Fair (5 out of 9)
Appraisal: Functionally obsolete
Sufficiency rating: 58.0 (out of 100)
Average daily traffic (as of 2014)
26,500

Update Log 

  • March 21, 2012: Posted HAER photos
  • August 31, 2011: Added by Luke Harden

Sources 

Comments 

Summer Street over Fort Point Channel Bridge
Posted November 1, 2016, by Clark Vance (cvance [at] dogmail [dot] com)

In November 1916 a streetcar went off this partially opened bridge, killing 46 people.

http://www.bostonglobe.com/metro/2016/10/29/trolleydisaster/...

Story includes animation of the unusual way the bridge opens.