Letter: Overpass choice must consider trade-offs, details

February 17, 2012
By

The article in the Feb. 3 Gazette on delays and traffic has a need for clarification (“Overpass delay continues”). I am the author of the traffic report submitted to state Rep. Liz Malia. I announced up front that I would not state a preference for either the bridge or the at-grade option. My job was to emphasize the pluses and minuses of each plan and to fill in some of the traffic numbers so that others can make a better and more accurate assessment.

My conclusions only peripherally dealt with national methods of performing traffic and safety studies. I addressed those issues by applying better engineering methods capable of giving a more accurate assessment of traffic impacts, as well as a projection of safety conditions. My conclusion remains that the state engineers used computer models that were not highly accurate and made no projections for future intersection accidents.

I urged all parties to keep the tradeoffs in mind when stating a preference. They should see the choice as not rigidly black-and-white. For example, the at-grade option has the advantage of no elevated structure, shadow, dirt and aesthetic damage, but at a price of an additional 19 accidents a year and a 350 percent increase in the amount of surface traffic along the Arborway corridor. I stressed that further mitigation could take the form of traffic calming and lane reductions that would prevent the creation of a “six-lane speedway.” In other words, problems of accidents and heavy surface traffic flows could be at least partially mitigated by additional sensitive design work—unfortunately not yet discussed. I highlighted other unresolved design issues, such as including special turning lanes for the 39 bus and three bus routes from Morton Street. At the time I met with the state engineers, they did not have a solution.

Finally, I am happy that the Gazette reported on the efforts of my state representative, Marty Walz, to work with Rep. Malia on the inflexibility of project deadlines. They have determined that the 2016 deadline is the result of a decision to sell 30-year bonds to finance this $50 million to $70 million project. Selling 20-year bonds is a better decision, and it removes the time pressures on a decision. Twenty-year bonds allow state debt to be paid off faster with lower interest costs. I am in favor of going further—10-year bonds—since this involves even lower interest payments. At a time when the state is struggling under $10 billion in Big Dig debt, any new bonds should be paid off quickly with projects that are trim and lean, without gold-plating. A $50 million plan not to build a bridge does appear to qualify as unduly extravagant.

Stephen H. Kaiser, Ph.D.

Cambridge

Best of JP 2014