Baltimore Harbor Tunnel is 50
The Baltimore Harbor Tunnel opened for traffic 50 years ago on Nov 29 and the event was hailed up adn down the east coast as the "Baltimore bottleneck unplugged." Motorists traveling from Philadelphia or New York to the national capital would no longer have to endure dozens of traffic signals on US1/US40 through the city - 51 by one count.
A journey of 45 minutes to an hour through the city was reduced to 20 minutes.
The Baltimore Sun editorialized at the time that it should improve local morale since Baltimoreans would cease to be subjected to the verbal assaults of "battalions of outlanders whose only acquaintance with the city has been in its capacity as a bottleneck." ('Outlanders' -there's a word that's died in 50 years! TRnews)
The tunnel was popular for more practical reasons as well. Baltimoreans had less congested local streets once the through-traffic was put in the tunnel and its associated 28km (18 mile) expressway called then the Harbor Thruway (now I-895).
Major issue in contention before it as built was whether the crossing should be a bridge or a tunnel. A bridge was strongly opposed by port interests. The Navy Department too opposed bridges over waterways that might be used by warships on the argument that in war the bridges might be attacked and the debris could block shipping channels.
The Governor of the time Theodore McKeldrin is said to have broken the political logjam by deciding for the tunnel.
At the opening the governor said the tunnel was "an important avenue of transportation, an important route of commerce, and an important element in our national mobility. The Harbor Thruway linked US40 Pulaski Highway on the northeastern outskirts of Baltimore with the Baltimore-Washington expressway (now Parkway) and to US1 in Elkridge southwest of Baltimore providing for travel to Washington DC and had a branch south to US301 to Annapolis. It had 12 interchanges, so served internal Baltimore movement also.
Ten years later it was linked to the Kennedy Highway at its northern end and to I-95 south, It got the I-95 designation which it retained until late 1985 when the parallel Ft McHenry Tunnel opened. The Harbor Tunnel then became I-895.
It was built by the Maryland State Roads Commission, the equivalent of the state DOT and later handed over to the separate toll agency Maryland Transportation Authority. There is no report we can find of how it was financed though it charged tolls from opening day. One fact sheet refers to construction cost as $130m and financing cost as $14m.
Opening tolls were 40c for cars and 85c for large trucks. They are now $2 for cars and up to $20 for trucks.
It was built of 21 x 91m (300ft) twin tube prefabricated steel segments built in a nearby Baltimore drydock, the segments being floated out and immersed so they went down into a dredged trench in the harbor where they were connected by divers - the immersed tube method of tunnel construction. The tunnel is 2.33km (1.45 miles) long.
It carries about 70k veh/day on its 4 lanes (2+2) and for the most part flows freely. Along with the later 8 lane Ft McHenry Tunnel there are 12 travel lanes under the harbor now although the larger tunnel at its southern end serves downtown Baltimore whereas the Harbor Tunnel takes a more southerly route and serves industrial areas, Annapolis, and the airport more directly. At the northern end the tunnel routes converge.
Before the extra crossings were built in the early 1980s traffic was over 90k/day in the Harbor Tunnel and it was often slow.
The roadway width of each tube is 6.7m (22ft) making for 3.35m (11ft) lanes with just under 4m (13ft) overhead clearance, no shoulders or offsets, but it has always carried normal tractor trailers without trouble.
The Harbor Tunnel was apparently well built and has been well maintained and continues to serve Maryland and the east coast well.
The Baltimore Sun's Michael Dresser has done a nice anniversary lookback from which some of this and most of the pictures are taken.
Referred to in Maryland Transportation Authority (MTA) reporting sometimes as Patapsco Tunnel, other times as the Baltimore Harbor Tunnel, it had 25.74m vehicles (av70.5k/day) in FY2007 v 26.3m vehicles (71.9k) in 2006. Only 4.2% are more than 2 axles.
Compared to 394k tractor trailers in 2007 (1.1k/day), the nearby Ft McHenry Tunnel carried 2,815k (7.7k/day) and there trucks constitute 10% of total traffic. Most of the port facilities are on the northern side served by the FtMcHenry.
E-ZPass transponder payment accounts for 58% of car tolls and 86% of tractor trailers.
Toll revenue last year was $34.7m compared to $35.1m the year before.