The Harvard Bridge (also known locally as the MIT Bridge, the Massachusetts Avenue Bridge, and the "Mass. Ave." Bridge) is a
steel
Steel is an alloy made up of iron with added carbon to improve its strength and fracture resistance compared to other forms of iron. Many other elements may be present or added. Stainless steels that are corrosion- and oxidation-resistant ty ...
haunched
girder bridge
A girder bridge is a bridge that uses girders as the means of supporting its deck. The two most common types of modern steel girder bridges are plate and box.
The term "girder" is often used interchangeably with "beam" in reference to bridge de ...
carrying
Massachusetts Avenue Massachusetts Avenue may refer to:
* Massachusetts Avenue (metropolitan Boston), Massachusetts
** Massachusetts Avenue (MBTA Orange Line station), a subway station on the MBTA Orange Line
** Massachusetts Avenue (MBTA Silver Line station), a stati ...
(
Route 2A) over the
Charles River
The Charles River ( Massachusett: ''Quinobequin)'' (sometimes called the River Charles or simply the Charles) is an river in eastern Massachusetts. It flows northeast from Hopkinton to Boston along a highly meandering route, that doubles b ...
and connecting
Back Bay
Back Bay is an officially recognized neighborhood of Boston, Massachusetts, built on reclaimed land in the Charles River basin. Construction began in 1859, as the demand for luxury housing exceeded the availability in the city at the time, and t ...
,
Boston
Boston (), officially the City of Boston, is the state capital and most populous city of the Commonwealth of Massachusetts, as well as the cultural and financial center of the New England region of the United States. It is the 24th- mo ...
with
Cambridge, Massachusetts
Cambridge ( ) is a city in Middlesex County, Massachusetts, United States. As part of the Boston metropolitan area, the cities population of the 2020 U.S. census was 118,403, making it the fourth most populous city in the state, behind Boston, ...
. It is the longest bridge over the
Charles River
The Charles River ( Massachusett: ''Quinobequin)'' (sometimes called the River Charles or simply the Charles) is an river in eastern Massachusetts. It flows northeast from Hopkinton to Boston along a highly meandering route, that doubles b ...
at .
After years of disagreement between the cities of Boston and Cambridge, the bridge was built jointly by the two cities between 1887 and 1891.
It was named for
Harvard University
Harvard University is a private Ivy League research university in Cambridge, Massachusetts. Founded in 1636 as Harvard College and named for its first benefactor, the Puritan clergyman John Harvard, it is the oldest institution of higher le ...
founder
John Harvard. Originally equipped with a central
swing span, it was revised several times over the years until its superstructure was completely replaced in the late 1980s due to unacceptable vibration and the collapse of a similar bridge in Connecticut.
The bridge is known locally for being marked off in the idiosyncratic unit of length called the
smoot
The smoot is a nonstandard, humorous unit of length created as part of an MIT fraternity prank. It is named after Oliver R. Smoot, a fraternity pledge to Lambda Chi Alpha, who in October 1958 lay down repeatedly on the Harvard Bridge (betwe ...
.
Conception
In 1874 the Massachusetts Legislature authorized construction of a bridge between Boston and Cambridge, and in 1882 follow-up legislation set out its location.
The bridge was to have a draw with an opening of at least . Boston interests opposed the bridge, mainly because it did not provide for an overhead crossing of the
Grand Junction Branch
Grand may refer to:
People with the name
* Grand (surname)
* Grand L. Bush (born 1955), American actor
* Grand Mixer DXT, American turntablist
* Grand Puba (born 1966), American rapper
Places
* Grand, Oklahoma
* Grand, Vosges, village and co ...
of the
Boston and Albany Railroad
The Boston and Albany Railroad was a railroad connecting Boston, Massachusetts to Albany, New York, later becoming part of the New York Central Railroad system, Conrail, and CSX Transportation. The line is currently used by CSX for freight. Pass ...
. Further legislation in 1885 changed the draw to a clear opening of at least and no more, until the other bridges below the proposed location were required to have a larger opening. There was still no substantive progress until 1887, when Cambridge petitioned the Legislature to compel Boston to proceed; the resulting act required each city pay half the cost, and allowed Boston to raise up to $250,000 (US$ with inflation) for this purpose, in excess of its
debt limit
A debt limit or debt ceiling is a legislative mechanism restricting the total amount that a country can borrow or how much debt it can be permitted to take on. Several countries have debt limitation restrictions.
Description
A debt limit is a l ...
. This implied an estimated cost of US$500,000 (US$ with inflation
) for the bridge.
The Legislature provided for a bridge commission, to consist of the mayors of Boston and Cambridge plus a third commissioner to be appointed by the mayors. The mayors of Boston and Cambridge,
Hugh O'Brien
Hugh O'Brien (July 13, 1827 – August 1, 1895) was the 31st mayor of Boston, from 1884 to 1888. O'Brien is notable as Boston's first Irish and Catholic mayor, having emigrated from Ireland to America in the early 1830s. O'Brien was the editor ...
and
William E. Russell, appointed Leander Greeley of Cambridge as the third commissioner, though this appointment changed over time.
The commission's 1892 report claimed:
Name
The bridge is named for the
Reverend John Harvard, for whom
Harvard University
Harvard University is a private Ivy League research university in Cambridge, Massachusetts. Founded in 1636 as Harvard College and named for its first benefactor, the Puritan clergyman John Harvard, it is the oldest institution of higher le ...
is also named, rather than for the university itself. Other names suggested included
Blaxton
Blaxton is a village in the Metropolitan Borough of Doncaster (part of South Yorkshire, England), on the border with Lincolnshire. It lies to the north of Finningley, on the A614 road, and is located at approximately 53° 29' 30" North, 0° 5 ...
,
Chester
Chester is a cathedral city and the county town of Cheshire, England. It is located on the River Dee, close to the English–Welsh border. With a population of 79,645 in 2011,"2011 Census results: People and Population Profile: Chester Loca ...
,
Shawmut Shawmut, according to 19th-century scholarship, is a term derived from the Algonquian word ''Mashauwomuk'' referring to the region of present-day Boston, Massachusetts.Forsford, Eben Norton, ''The Indian names of Boston, and their meaning''Univer ...
, and
Longfellow
Henry Wadsworth Longfellow (February 27, 1807 – March 24, 1882) was an American poet and educator. His original works include "Paul Revere's Ride", ''The Song of Hiawatha'', and ''Evangeline''. He was the first American to completely transl ...
.
Engineering
![Harvard Bridge postcard, 1910](https://upload.wikimedia.org/wikipedia/commons/7/7a/Harvard_Bridge_postcard%2C_1910.jpg)
Originally projected as a wooden pile structure with stone pavement for the first (because the Charles River Embankment extension was expected to take that space) the design was changed to be entirely iron spans on stone piers. The general plans were approved on July 14, 1887. The engineers were
William Jackson (Boston City Engineer), John E. Cheney (assistant Boston City Engineer), Samuel E. Tinkham (assistant engineer), and Nathan S. Brock (assistant engineer at bridge).
The subsurface conditions at the bridge location are extreme. Much of Boston is underlain with clay, but the situation at the bridge is exacerbated by a fault which roughly follows the path of the Charles River itself. From a depth of approximately below existing ground, is a very dense till composed of gravel and boulders with a silt-clay matrix. Above that to approximately below the surface is Boston blue clay (BBC). Over this are thin layers of sand, gravel, and fill. The BBC is
overconsolidated up to a depth of approximately .
The substructure originally consisted of two masonry abutments and twenty-three masonry piers, as well as one pile foundation with a
fender pier for the draw span. The superstructure was originally twenty-three
cantilevered fixed spans and suspended spans, of plate girders with one
swing span. The Boston abutment rests on vertical piles, while the Cambridge end is directly on gravel.
Originally, the bridge was built across the Charles River connecting West Chester Park, in Boston, with Front Street, in Cambridge. This is now called
Massachusetts Avenue Massachusetts Avenue may refer to:
* Massachusetts Avenue (metropolitan Boston), Massachusetts
** Massachusetts Avenue (MBTA Orange Line station), a subway station on the MBTA Orange Line
** Massachusetts Avenue (MBTA Silver Line station), a stati ...
on both sides of the river. As originally built, the total length between centers of bearings on abutments was with a draw wide between centers. The width of the bridge was except near and on the draw.
The bridge as built was composed of fixed and suspended spans roughly long and piers apart, center to center. The span lengths alternated between . The longer spans were cantilevered, while the shorter spans were suspended between the cantilevers.
The original roadway contained two lanes for horse-drawn vehicles and two street car tracks, for a total width of . There were also two sidewalks.
[HAER, p. 3] The original roadway and sidewalk stringers were of wood, with an approximately thick covering of asphalt on the sidewalk and a spruce wearing surface on the roadway.
The exception was at the swing span, which was wide. This span was approximately long, and sat on a wooden pier. It was a double-cantilevered, electrically-driven structure also carrying a bridge caretaker's house.
The bridge opened on September 1, 1891. The original cost of construction was $511,000, $ in current dollars.
Maintenance and events
![After Harry Houdini jumps off Harvard Bridge in Boston 1908](https://upload.wikimedia.org/wikipedia/commons/3/35/After_Harry_Houdini_jumps_off_Harvard_Bridge_in_Boston_1908.jpg)
In 1898, bicycle lanes were installed next to each curb.
In 2011 (113 years later), the City of Boston finally connected these lanes to its own bike lanes.
A marker near the southeast end of the bridge memorializes one of
Harry Houdini
Harry Houdini (, born Erik Weisz; March 24, 1874 – October 31, 1926) was a Hungarian-American escape artist, magic man, and stunt performer, noted for his escape acts. His pseudonym is a reference to his spiritual master, French magician ...
's "well known escapes", during which he jumped from the bridge on May 1, 1908. (Other sources give the date as April 30, 1908.)
[
]
The bridge was declared unsafe in 1909, requiring all of the iron and steel to be replaced. The draw was elevated slightly and the trolley rails were replaced as well.
When the Metropolitan District Commission (MDC) took control of the bridge in 1924, they rebuilt much of the bridge superstructure. They replaced the wooden stringers with steel "I" beams, topped wooden deck elements with concrete and brick, and replaced the street car rails.
Structural steel hangers replaced wrought iron. The swing span was converted into two fixed spans the same width as the rest of the bridge. The wooden pier was heavily modified with concrete and stone to make it resemble the other piers, increasing the number of stone piers from 23 to 24.
[HAER, p.4]
Heavy traffic at the
Mass Ave and Memorial Drive intersection on the Cambridge end of the bridge led to the construction of an underpass in 1931.
[HAER, p. 5]
The bridge was formerly referred to as the "Xylophone Bridge" because of the sound its wooden decking made when traffic traveled over it. This decking was replaced in 1949 with concrete-filled "I-beam lok" grating topped with a thick bituminous wearing surface. At this time, all bearings were replaced, and the trolley car tracks were removed, as were granite blocks. The trolley car poles were reused for street lights. Ramps between the bridge and the under-construction
Storrow Drive
Storrow Drive, officially James Jackson Storrow Memorial Drive, is a major crosstown parkway in Boston, Massachusetts, running east–west along the southern bank of the Charles River. It is restricted to cars; trucks and buses are not perm ...
were added.
The 1924 sidewalk slabs were replaced by precast, prestressed slabs in 1962.
The fifteen expansion dams were replaced or repaired in 1969.
[HAER, p.6]
Engineering study, 1971–1972
![Harvard Bridge Art](https://upload.wikimedia.org/wikipedia/commons/9/9e/Harvard_Bridge_Art.JPG)
An engineering study was performed by the Metropolitan District Commission (later merged into the
Department of Conservation and Recreation
The Department of Conservation and Recreation (DCR) is a state agency of the Commonwealth of Massachusetts, situated in the Executive Office of Energy and Environmental Affairs. It is best known for its parks and parkways. The DCR's mission is ...
) in 1971–1972 due to complaints by bridge users of excessive vibration.
[Leet, phase 2] The bridge was found to be understrength for its load. Before the final study was complete, the recommendation was to place a load limit of per axle and a total of per vehicle, or to restrict trucks to the interior lanes, where the bridge was stronger. A limit was imposed.
[Leet, phase 3]
Suggestions made included strengthening the existing structure by adding either struts or plates to make the existing four beams along the length of the bridge into a stiffening truss, or to replace the superstructure with a new one, made of either steel or concrete, which would be up to current standards.
The recommendation was to replace the superstructure with one weighing approximately the same in order to reuse the piers, which were in good condition.
The reasoning was that the cost of a new structure could be predicted much more easily than the cost of repairing and reinforcing the existing bridge. The resulting new bridge would be of known materials and quality, such as ductile structural steel rather than brittle wrought iron, and rated at
AASHO
The American Association of State Highway and Transportation Officials (AASHTO) is a standards setting body which publishes specifications, test quality control, protocols, and guidelines that are used in highway design and construction through ...
HS-20. Repairing the existing structure would leave old wrought iron of uncertain quality and condition standing, and would not bring the design up to (then) current standards.
Detailed engineering calculations were included.
[Leet, phase 3, appendices] The price was estimated at US$2.5 million to US$3 million
(US$ to US$ with inflation
).
The action taken based on this study was to establish load restrictions on the bridge, in the outer lanes, on the inner lanes. This was expanded in 1979 to a flat limit of on the whole bridge.
[HAER, p.8]
Superstructure replacement, 1980s
After the failure of the
Mianus River Bridge at
Greenwich, Connecticut
Greenwich (, ) is a New England town, town in southwestern Fairfield County, Connecticut, United States. At the 2020 United States Census, 2020 census, the town had a total population of 63,518. The largest town on Connecticut's Gold Coast (Conne ...
in 1983, the Harvard Bridge was shut down and inspected because it contained similar elements, specifically the suspended spans. Traffic was restricted to the inner two lanes due to the discovery of two failed hangers on span 14. A few days later, all trucks and buses were banned from the bridge.
In 1986, a report was published containing the plan to replace the superstructure on the existing supports. Alternatives considered were very similar to the
1972 report, and were similarly decided.
[Replacement, p.7] Structural modifications included an upgrade from four longitudinal girders to six of the same shape and replacement of a stairway with a handicapped pedestrian ramp on the Boston end of the bridge.
[Replacement, p.4]
Ramp "B", from southbound (Boston bound) bridge lanes to eastbound
Storrow Drive
Storrow Drive, officially James Jackson Storrow Memorial Drive, is a major crosstown parkway in Boston, Massachusetts, running east–west along the southern bank of the Charles River. It is restricted to cars; trucks and buses are not perm ...
, caused traffic to merge onto Storrow Drive from the left (high speed) lanes using a short acceleration lane, causing safety issues. The MDC requested elimination of this ramp. Compared to overall bridge traffic of 30,000 vehicles per day, traffic on ramp B was found to be low, approximately 1,500 vehicles per day with a peak of 120 vehicles per hour.
[Replacement, page 4-6]
The historic value of the bridge was considered significant, so the plan was to make the replacement superstructure appear similar, with similar railing and lighting. In order to document the pre-existing structure, a Historic American Engineering Record (HAER) would be prepared.
[Replacement, p.11. Note the use of the HAER document throughout this article.]
Pier 12 was exhibiting inappropriate movement and was scheduled for reinforcement.
[Replacement, page 5]
The work would be done in two phases. Phase 1 would reinforce the downstream side of the bridge to allow MBTA bus traffic, and was expected to take 5 months. Most of this effort would be spent on the underside of the bridge and would not affect existing traffic. Phase 2 would replace the entire superstructure and was expected to take three construction seasons to implement. Cost was estimated to be
(US$ with inflation
). Phase 1 finished in 1987, and Phase 2 in 1990.
File:Harvard Bridge, Spanning Charles River at Massachusetts Avenue, Boston ( Suffolk County, Massachusetts).jpg, Bridge viewed from the upstream Cambridge side in 1985. Construction barrels restricting traffic from the outside lanes, and general wear and tear are visible (click on image to enlarge)
File:Harvard Bridge from Cambridge, 2009.jpg, Roughly the same view, in 2009. Superstructure is in much better shape only 20 years after completion, than the 1985 superstructure was roughly 40 years after its most recent major work.
File:Underside, centerline, 1985.jpg, Underside of the bridge in 1985. Image shows how the bridge was originally built, and later modified, but before the superstructure was replaced.
File:Harvard Bridge, centerline, looking north, 2009.jpg, Underside of the bridge in 2009. Image shows how the replacement superstructure was built, with six longitudinal girders, different bracing, etc.
Subsequent events
In the fall of 2014, the Charles River Conservancy announced that an anonymous donor would fund an upgrade of the street lights for both the roadway and both sidewalks on the bridge. The new roadway and aesthetic lighting was installed in 2015, highlighting the smoot marks along the sidewalk. The design was selected after a competition won by
Miguel Rosales
Miguel Rosales (born 1961 in Guatemala) is president and principal designer of Rosales + Partners, an architecture firm based in Boston, Massachusetts. He specializes in bridge aesthetics and design. Some examples of these bridges include; Phyl ...
of Rosales + Partners. The light posts will be located apart.
"It will provide safe lighting for pedestrians and drivers, and the elements of design on the bridge will be pulled out and emphasized. It will become a really beautiful bridge," said Renata von Tscharner, founder and president of the Charles River Conservancy.
Smoots
![Smoot mark 210, east](https://upload.wikimedia.org/wikipedia/commons/c/c8/Smoot_mark_210%2C_east.jpg)
The Harvard Bridge is marked off in an idiosyncratic unit of measure, the
smoot
The smoot is a nonstandard, humorous unit of length created as part of an MIT fraternity prank. It is named after Oliver R. Smoot, a fraternity pledge to Lambda Chi Alpha, who in October 1958 lay down repeatedly on the Harvard Bridge (betwe ...
.
In 1958, members of the
Lambda Chi Alpha
Lambda Chi Alpha (), commonly known as Lambda Chi, is a college fraternity in North America which was founded at Boston University in 1909. It is one of the largest social fraternities in North America, with more than 300,000 lifetime members a ...
fraternity at
MIT
The Massachusetts Institute of Technology (MIT) is a private land-grant research university in Cambridge, Massachusetts. Established in 1861, MIT has played a key role in the development of modern technology and science, and is one of the m ...
measured the bridge's eastern sidewalk by using that year's shortest
pledge
Pledge may refer to:
Promises
* a solemn promise
* Abstinence pledge, a commitment to practice abstinence, usually teetotalism or chastity
* The Pledge (New Hampshire), a promise about taxes by New Hampshire politicians
* Pledge of Allegianc ...
,
Oliver Smootnominally, tallas a measuring stick.
Years after this stunt, Smoot became president of the
American National Standards Institute
The American National Standards Institute (ANSI ) is a private non-profit organization that oversees the development of voluntary consensus standards for products, services, processes, systems, and personnel in the United States. The organi ...
(ANSI), and later president of the
International Organization for Standardization
The International Organization for Standardization (ISO ) is an international standard development organization composed of representatives from the national standards organizations of member countries. Membership requirements are given in Ar ...
(ISO).
Markers painted at intervals give the bridge's length 364.4
smoot
The smoot is a nonstandard, humorous unit of length created as part of an MIT fraternity prank. It is named after Oliver R. Smoot, a fraternity pledge to Lambda Chi Alpha, who in October 1958 lay down repeatedly on the Harvard Bridge (betwe ...
s long, "plus one ear". Originally this read "plus or minus one ear"representing measurement uncertaintybut over the years the words "or minus" disappeared.
The marks are repainted twice each year by members of the fraternity
originally surreptitiously and later openly.
During the major reconstruction in the 1980s, the new sidewalks were divided into
smoot
The smoot is a nonstandard, humorous unit of length created as part of an MIT fraternity prank. It is named after Oliver R. Smoot, a fraternity pledge to Lambda Chi Alpha, who in October 1958 lay down repeatedly on the Harvard Bridge (betwe ...
-length slabs rather than the standard six feet, and the smoot markings were painted on the new deck.
Officials' original determination to omit the smoot markings from the reconstructed bridge, and to scrupulously prevent the fraternity from repainting them, evaporated when it was realized that police routinely used the smoot marks as reference points in accident reports.
The nominal length of 364.4 smoots (from two designated points at the bridge's ends) corresponds to about 2030 feet or 620 m, somewhat less than the bridge's published length of .
A possible cause is that in 1958, there were ramps to
Storrow Drive
Storrow Drive, officially James Jackson Storrow Memorial Drive, is a major crosstown parkway in Boston, Massachusetts, running east–west along the southern bank of the Charles River. It is restricted to cars; trucks and buses are not perm ...
on both sides of the bridge, which interrupted the sidewalk earlier than it extends today. A bridge of
[Alger and Matthews, p. 17] corresponds to 387.7 smoots ± one ear.
See also
*
*
List of crossings of the Charles River
This is a list of the crossings of the Charles River from its mouth at Boston Harbor upstream to its source at Echo Lake (the four tunnels crossing the inner portion of Boston Harbor are not included). All locations are in Massachusetts.
__TOC_ ...
References
Informational notes
Citations
Bibliography
* (Nationalbridges.com): ''Note'': this is a formatted
scrape of the 2009 official website, which can be found here for Massachusetts:
*
*
* (Replacement): Submitted pursuant to 42 U.S.C. 4332 (2) (c), and 23 U.S.C. 128 (a).
*
*
External links
*
1895 photo
{{Crossings navbox
, structure =
Crossings
Crossings may refer to:
* ''Crossings'' (Buffy novel), a 2002 original novel based on the U.S. television series ''Buffy the Vampire Slayer''
* Crossings (game), a two-player abstract strategy board game invented by Robert Abbott
* ''Crossings'' ...
, place =
Charles River
The Charles River ( Massachusett: ''Quinobequin)'' (sometimes called the River Charles or simply the Charles) is an river in eastern Massachusetts. It flows northeast from Hopkinton to Boston along a highly meandering route, that doubles b ...
, bridge = Harvard Bridge
, bridge signs =
, upstream =
Boston University Bridge
The Boston University Bridge, originally the Cottage Farm Bridge and commonly referred to as the BU Bridge, is a steel truss through arch bridge with a suspended deck carrying Route 2 over the Charles River, connecting the Boston University ca ...
, upstream signs =
, downstream =
Longfellow Bridge
The Longfellow Bridge is a steel rib arch bridge spanning the Charles River to connect Boston's Beacon Hill neighborhood with the Kendall Square area of Cambridge, Massachusetts. The bridge carries Massachusetts Route 3, US Route 3, the MBTA R ...
, downstream signs =
Bridges completed in 1891
Bridges in Boston
Historic American Engineering Record in Massachusetts
Landmarks in Back Bay, Boston
Landmarks in Cambridge, Massachusetts
Massachusetts Institute of Technology
Massachusetts Institute of Technology student life
Buildings and structures in Cambridge, Massachusetts
Transportation in Cambridge, Massachusetts
Bridges in Middlesex County, Massachusetts
Road bridges in Massachusetts
1891 establishments in Massachusetts
Bridges over the Charles River
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