Monday, December 21, 2015

Why a new or wider Bay Bridge would be the wrong answer

The Maryland Transportation Authority (MDTA) gave us the oh so useful $1.1 billion I-95 express toll lanes north of the Harbor Tunnels and the equally underperforming  $2.5 billion Intercounty Connector.

So we naturally couldn't wait until we heard about  the next big billion dollar boondoggle the MDTA wants to sell to politicians and constituents. (I really like how the Governor enriched the discourse of the transportation debate with this technical term, for indeed, the transport industry is right up there with the military and Hollywood when it comes to the production of boondoggles.)

The two spans of the Chesapeake Bay Bridge built in 1952 and 1973

Just in time for Christmas we received the latest multi billion dollar MDTA wish wrapped nicely in a "life cycle cost analysts". That sounds pretty scientific, and loaded with options, statistics and tables  the report looks the part even if any sane person would find projections 50 years forward a very daring exercise. But aside from that, as the saying goes, "garbage in, garbage out".

This isn't to say that the report in itself is unprofessional, faulty or flawed, far from me to even judge that! What I am saying is that the report asks the wrong questions and therefore gives the wrong answers, just like that scientific analysis some 120 years ago that tried to gauge the depth of horse manure on London's streets by extrapolating the conditions of 1894 into the year 1944. We all know how that went.

The existing Bay Bridge structures are currently in satisfactory condition. The structural analysisshows that with programmed and anticipated rehabilitation and maintenance the existing structures can be maintained in fair or better condition through 2065, at which point the eastbound structure will be 113 years old and the westbound structure will be 92 years old. Beyond 2065, it is difficult to project whatrehabilitation and maintenance would be required to keep the bridgesin fair or better condition, but it is likely that major rehabilitation projects would be required that would necessitate extensive short‐term and/or long‐term lane closures. These future projects could have a major, detrimental impact on available bridge capacity and operations. Therefore, 2065 wasidentified asthe horizon year for when Bay Bridge improvements would have to be implemented. (Report)

The Bay Bridge study is a bit like the horse manure crisis of 1894 when it tries to paint a picture of horrible congestion by 2040 at a time in transportation history which could turn out to be just as transformative as the shift from horses to cars 100 years ago. Instead of increasing from today's 70,000 vehicles to 92,000 a day by 2040 (with 125,000 in the summer peak), the traffic counts could actually go down even if population increase and attractiveness of the Eastern Shore as a place to live should continue.


Just assume that the technological advance of the autonomous vehicle (AV) will make more people realize that the transportation model of the self-owned single occupant car that sits around unused for about 95% of the time is obsolete. Just assume more people would prefer the car sharing "Uber model", just without a driver, and imagine further how self driving cars could act like huge trains, especially when it comes to traversing the Bay Bridge. With those assumptions congestion would certainly go down and possibly even the number of trips because of pooled vehicles. AVs could potentially increase capacity by 50%. 

In addition to this, the trend to urban living could continue and break or weaken the attraction of the Eastern Shore as a giant bedroom community with the jobs on the other side of the Bay. This consideration is important even before we talk about climate change, rising sea levels and environmental protection as variables that could reduce travel and especially commuting demand as well, namely because large parts of the developable areas on the Eastern Shore lie within the threat zones. 
Chester /Stephensville, the first communities on the Eastern
Shore side of the Bay Bridge have seen significant growth.
The ongoing car centric efforts of rapid travel to the beach
has all but ruined the character of the Eastern Shore along
the first several miles after the bridge

None of this is certain at this point and nobody knows how trends will unfold by 2040 or 2065 a full 25 or 50 years years from now. (Just think 25 years back: In 1990 the Internet had just begun, there was no Amazon, no hybrid cars and cities were roiling from abandonment across the country).

Lastly, and maybe most importantly, even if everything would just continue to be as it is today (as the study assumes), we know that adding capacity does not solve congestion! It simply creates new (induced) demand inviting more people to live on the Eastern Shore and pave over the landscapes and shorelines that need to remain pristine or should be restored to be pristine again so they can help bring back the waters of the Bay to healthy conditions. Doing that would be a crime against the lands and the waters we all love. 

Therefore, considerations about the future mobility in the larger region should begin with acceptable outcomes and work out how those outcomes can be achieved instead of open ended extrapolations of current utterly unsustainable trends. 

Klaus Philipsen, FAIA

The author participated in a 2004 growth management masterplan for the Stevensville/Chester area of Queen Anne's County on the Eastern Shore. The matter was too controversial to be adopted. It died in the local Citizen Advisory Committee which was split over the issue. 

1 comment:

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