Another bad crash on Maryland's Chesapeake Bay Bridge in two-way traffic

Maryland's notorious Chesapeake Bay Bridge suffered another fatal collision in two-way traffic on Sunday morning. A tractor trailer struck a car in the opposing direction of traffic at around 4am, lost control, neatly punched out a section of concrete parapet and plunged 10m (35ft) into the waters of the Bay.

The driver was killed.

Two women in another vehicle were badly injured but are recovering.

Disruption to normal traffic was enormous and made travel a misery for about 100,000 people.

A barge-mounted crane retrieved the wreckage of the tractor trailer from the waters of the Bay today.

Aerial photographs nearby (all from NBC4 TV) clearly show black skid marks on the bridge deck leading to the missing section of parapet that was knocked out by the errant tractor trailer.

It was a load of frozen chicken from a farm and processing plant in Delaware headed for supermarkets in the DC area.

There were reports that motorists were delayed up to 5 hours and there were backups of 20km (13 miles). It took some 36 hours for normal traffic to be restored.

BACKGROUND: The bridge which carries US50 and US301 is operated by the Maryland Transportation Authority, the state toll authority and collects tolls at an 11 lane stop-to-pay toll plaza located on the western side near Annapolis. Tolls are taken from eastbound traffic only.

Formally the Chesapeake Bay Bridge (just the Bay Bridge in normal local parlance) this is the only link between the Eastern shore and the Washington-Baltimore metro area (7.8m pop). The bridge consists of an older 2-lane span normally used for eastbound traffic and a 3-lane span for westbound traffic. It is just under 7km (4.3 miles) shore to shore. Most is over shallow Bay waters but in the center there are suspension spans rising to about 60m (190ft) clearance over the shipping channel between the Atlantic Ocean and the port of Baltimore.

The southern span designed to replace ferries is 56 years old (opened 1952-07-30) and was built to 1950s standards when trucks were lighter and smaller. The span has a two 3.81m (12.5ft) travel lanes with offsets against each parapet of 0.43m (1.42ft) for a total deck width of 8.48m (27.8ft).

The second span which is 35 years old (opened 1973-06-28) has three 3.66m (12ft) travel lanes with a 0.3m (1ft) offset each side for a deck width of 11.58m (38ft).

Both spans operate contra-flow (both directions) on a fairly regular basis.

There's a 50mph (80km/hr) posted speed limit on the bridge.

Average daily traffic is 65k (2004 data) but there are strong peaks at weekends because of its support for second houses and the beaches with traffic on Saturdays reaching 92k.

Trucks, much more steady in volume vary between a low of 5% in summer peaks and a high of 14% in winter off-peak times.

Daily commuting across the bridge into the Annapolis/Washington/Baltimore area is developing because housing is cheaper on the eastern shore.

Needs report

A Bay Bridge Needs Report in 2004 found that level of service currently E/F eastbound for several hours during summer weekend peak hours will worsen by 2025 to E/F for up to 12 hours per day on summer Saturdays and for several hours during average weekday afternoon peaks.

The report also noted that:

- there is a high incidence of accidents on the bridge relative to surrounding roads

- the lack of truck climbing lanes limits capacity

- lack of any breakdown shoulder or even refuges for disabled vehicles causes small breakdowns and collisions to generate major backups

- the strained condition of capacity makes for a big increase in congestion when maintenance work has to be performed

- there is little hurricane evacuation capacity

Aesthetic atrocity

The bridge is an exceedingly ugly structure of fussy truss work, different structural forms and jarring transitions. The towers of the two spans have nothing in common and the spans wander across the Bay in discordant curves.

Dangerous contraflow

The last serious accident also occurred in two way traffic but on the 3-lane westbound span about 15 months ago (May 2007). In that crash a trailer came loose from an SUV and three people were killed in a seven vehicle collision. At least on that occasion the parapets kept the wreckage from falling off the bridge.

FUTURE: There are three travel lanes each direction on the approach roads on either side of the Bay Bridge so the 2-lane eastbound span is an anomaly.

Functionally obsolete this old span needs to be put into semi-retirement as a reserve span, and a third span of at least three lanes plus truck climbing lane and breakdown shoulder built for regular eastbound traffic.

A new span would end the need to do dangerous two-way operations. And it could be built with parapets strong enough to contain a tractor-trailer!

Successive state governments and the Maryland Transportation Authority have failed to modernize the Bay Bridge - despite the fact that they have a ready source of funding for improvements in toll revenues.

If Maryland Transportation Authority continues to procrastinate on a new span the state could call for private sector proposals based on a longterm toll concession on the bridge.

TOLLROADSnews 2008-08-11