The Fort McHenry Tunnel is a four-tube, bi-directional

tunnel A tunnel is an underground passageway, dug through surrounding soil, earth or rock, and enclosed except for the entrance and exit, commonly at each end. A pipeline is not a tunnel, though some recent tunnels have used immersed tube cons ...

that carries traffic on

Interstate 95 Interstate 95 (I-95) is the main north–south Interstate Highway on the East Coast of the United States, running from U.S. Route 1, US Route 1 (US 1) in Miami, Miami, Florida, to the Houlton–Woodstock Border Crossing between M ...

(I-95) underneath the

Baltimore Baltimore ( , locally: or ) is the List of municipalities in Maryland, most populous city in the U.S. state of Maryland, fourth most populous city in the Mid-Atlantic (United States), Mid-Atlantic, and List of United States cities by popula ...

Harbor A harbor (American English), harbour (British English; see spelling differences), or haven is a sheltered body of water where ships, boats, and barges can be docked. The term ''harbor'' is often used interchangeably with ''port'', which is a ...

. The lowest point in the Interstate System under water, the tunnel is named for nearby

Fort McHenry Fort McHenry is a historical American coastal pentagonal bastion fort on Locust Point, now a neighborhood of Baltimore, Maryland. It is best known for its role in the War of 1812, when it successfully defended Baltimore Harbor from an attack b ...

. The tunnel was constructed from May 1980 to November 1985, at a cost of about $750 million. At the time of its opening on November 23, 1985, it was the most expensive underwater tunnel project in the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...

, but that figure has since been surpassed by the

Big Dig The Central Artery/Tunnel Project (CA/T Project), commonly known as the Big Dig, was a megaproject in Boston that rerouted the Central Artery of Interstate 93 (I-93), the chief highway through the heart of the city, into the 1.5-mile (2.4& ...

project in

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 ...

.DCRoads.net
"Fort McHenry Tunnel: Historic Overview"
Accessed 2011-07-11. The tunnel's annual traffic in 2009 was 43.4 million vehicles. , the toll rate for cars is $4.00 cash or $3.00 E-ZPass, paid in both directions. Vehicles with more than two axles pay additional amounts, up to $30.00 for six axles."MdTA toll rates: Baltimore Harbor Tunnel, Fort McHenry Tunnel and Francis Scott Key Bridge"
Accessed 2016-07-26. In March 2020,

all-electronic tolling Open road tolling (ORT), also called all-electronic tolling, cashless tolling, or free-flow tolling, is the collection of tolls on toll roads without the use of toll booths. An electronic toll collection system is usually used instead. The ma ...

was implemented as a result of the

COVID-19 pandemic The COVID-19 pandemic, also known as the coronavirus pandemic, is an ongoing global pandemic of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The novel virus was first identif ...

, with tolls payable through E-ZPass or

Video Tolling Video tolling (sometimes referred to as video billing, toll by plate, pay by mail, or pay by plate) is a form of electronic toll collection, which uses video or still images of a vehicle's license plate to identify a vehicle liable to pay a road ...

, which uses

automatic license plate recognition Automatic number-plate recognition (ANPR; see also other names below) is a technology that uses optical character recognition on images to read vehicle registration plates to create vehicle location data. It can use existing closed-circuit tel ...

. All-electronic tolling was made permanent in August 2020. In 2022, work began to remove the toll plaza as it was replaced with toll gantries.

Location

The tunnel crosses the

Patapsco River The Patapsco River mainstem is a U.S. Geological Survey. National Hydrography Dataset high-resolution flowline dataThe National Map , accessed April 1, 2011 river in central Maryland that flows into the Chesapeake Bay. The river's tidal port ...

, just south of Fort McHenry and connects the Locust Point and Canton areas of Baltimore City.

Design and construction

Plans for a second crossing of the Baltimore Harbor that would become the Fort McHenry Tunnel began in the late 1960s. Early plans called for an 8-lane

double-deck bridge A bridge is a structure built to span a physical obstacle (such as a body of water, valley, road, or rail) without blocking the way underneath. It is constructed for the purpose of providing passage over the obstacle, which is usually somethi ...

to carry I-95 over the harbor just south of Fort McHenry. In 1975, plans were changed from a bridge to a tunnel when it was determined that a bridge would have detrimental impact on Fort McHenry's status as a national monument. The state of

Maryland Maryland ( ) is a state in the Mid-Atlantic region of the United States. It shares borders with Virginia, West Virginia, and the District of Columbia to its south and west; Pennsylvania to its north; and Delaware and the Atlantic Ocean to ...

originally intended to build the tunnel with a reinforced concrete box design, but plans were changed in February 1976 to use a steel tubular design after a dispute with the

Federal Highway Administration The Federal Highway Administration (FHWA) is a division of the United States Department of Transportation that specializes in highway transportation. The agency's major activities are grouped into two programs, the Federal-aid Highway Program a ...

. The tunnel was to be constructed using the immersed tube method, with prefabricated tubes sunken into the harbor. Construction began in May 1980 by K-R-T (a

joint venture A joint venture (JV) is a business entity created by two or more parties, generally characterized by shared ownership, shared returns and risks, and shared governance. Companies typically pursue joint ventures for one of four reasons: to acces ...

between Peter Kiewit Sons Company, Raymond International Builders, and Tidewater Construction Corporation), and was completed in November 1985. 90 percent of construction costs were covered by federal funding, while 10 percent came from state funding. The tunnel consists of 32 tube sections, each wide and tall. The east and west approaches are and long, respectively. The opening of the tunnel closed a gap that previously existed in I-95 through Maryland."The Fort McHenry Tunnel."
Fact sheet. The Fort McHenry Tunnel was opened on time and under its budget, and it continues to be a vital transportation link in the Mid-Atlantic region. Soon after the Fort McHenry Tunnel opened, the nearby Baltimore Harbor Tunnel, which had opened to traffic in 1957, was extensively rehabilitated.

References

External links

Fort McHenry Tunnel
��history and technical info by Roads to the Future {{Baltimore bridges and tunnels Crossings of the Patapsco River Transportation buildings and structures in Baltimore Toll tunnels in Maryland Tolled sections of Interstate Highways Interstate 95 Tunnels completed in 1985 Articles containing video clips Road tunnels in Maryland Immersed tube tunnels in the United States

Location

Design and construction

See also

References

External links