Cambridge streets will become ever more choked with traffic and its public transit systems will be overwhelmed if proposed zoning changes to allow massive new development go forward, according to experts at a recent traffic forum sponsored by the Cambridge Residents Alliance.

Steve Kaiser, a traffic engineer working with the alliance, said the only way the city has been able to claim the existing transportation infrastructure can handle the huge traffic increase — estimated to be at least 50,000 additional car trips per day — is by focusing on certain intersections and ignoring others. “They simply refuse to look at the bottlenecks,” he told more than 70 people who attended the November 17 forum at the Senior Center in Central Square.

“I was told by a staff person in the city’s traffic department that if they included the bottlenecks in their study, they would not be able to justify any new development…Instead, they focus only on what I call the ‘puff-ball’ intersections and then come to the conclusion that everything will be all right.”

The City Council is being asked to consider “up-zoning” plans that will allow greatly increased building height and density in Central Square. While some plans are still fluid and others not yet disclosed, consultants and city advisors have discussed allowing multiple buildings of 16 stories and higher along Mass. Ave. and Bishop Allen Drive in recent public meetings.

Those plans are only one part of a much bigger citywide development picture, according to Richard Krushnic, a housing professional and Inman Square resident who spoke at the forum. Cambridge is looking at some 18 million square feet of new office, lab, and housing space, if all proposed projects citywide are taken into account, he said.

Yet development plans for each individual area are usually presented piecemeal, without a plan for the entire transportation and utilities infrastructure that would be needed to accommodate the increased density. The impact of such growth on subway travel would be just as grim as that on street traffic, said Jonathan King, an Area 4 resident whose panel presentation focused on public transportation. Reviewing studies of Red Line capacity and growth, King said all projections indicate the Red Line through Cambridge will soon be at “crush capacity” – the MBTA’s designation for cars in which all seats are filled and standing passengers are packed together – for much longer periods of time.

King presented the MBTA capital budget for the next five years, showing funds for upgrading the existing 218 Red Line cars, but no funds available for purchase of new cars needed to handle the increased burden. He argued that adding millions of square feet of new buildings in Central and Kendall Squares, knowing that thousands of additional commuters would more than saturate the T capacity, was poor policy.

City Councilor Minka vanBeuzekom, Chair of the Council’s Parking & Transportation Committee, spoke about the city’s measures to mitigate traffic and parking difficulties, and what still needs to be done. While Cambridge has launched significant programs to encourage walking and biking to work, carpooling, shuttles, and the use of public transit, there is still cause for concern going forward, she said. One way of estimating car ownership in Cambridge shows it going up and this was confirmed after the talk by actual vehicle numbers from 1960 to 2009. She stated Cambridge needs an better on-street parking census, nonsegmented traffic studies, increased enforcement, and other measures. In particular, we need a rigorous evaluation of the numerous traffic reduction measures taken over the years, she noted.

In his presentation, Krushnic displayed several graphs showing current square footage of commercial and residential property in Cambridge and projected citywide buildout by 2035 — both what is allowed under current zoning and what would be allowed under several proposed area up-zonings. This buildout would increase built space by 24% with alarming implications for a much more gentrified city, he noted, and at least 50,000 additional car trips and 50,000 additional public transit trips per day. Nearly half of this additional development would occur in greater Kendall Square, and another large share in Northpoint. Central Square could see 10-, 12-, and 16-story residential towers where public parking lots now stand. He observed that plenty of development can take place without the proposed up-zoning. Developers can build 6 or 7 stories on Mass. Ave. and still make money; they don’t need 12- or 16-story buildings to make a profit.

Kaiser drew appreciative laughter by displaying a beer bottle to illustrate how the rate of a liquid’s flow is determined by the narrower “neck” of a bottle rather than its larger “body.” In the same way, heavy traffic at crucial intersections or rotaries such as the BU Bridge, Alewife, Fresh Pond and Central Square, must narrow and squeeze to move forward. Kaiser showed a map from a traffic study done by the city that highlights a handful of intersections around Central Square that have little or no congestion, while ignoring intersections that represent bottlenecks. From that, the study makes the claim that traffic flow isn’t a problem in the Central Square district. He offered his alternative display of area intersections where traffic flow is slow and dangerous, and certain to become much more so if intensive development occurs. Also on display at the back of the room was a board of photos, showing minute-by-minute traffic progress at Central Square’s most congested intersection, Mass Ave. and Prospect Street. The pictures speak for themselves, showing the same vehicle inching along through 3 and 4 signal changes. 

Nancy Ryan, co-chair of the Cambridge Residents Alliance and former director of the Cambridge Women’s Commission, moderated a spirited and respectful discussion following the presentations. Participants expressed a range of diverse and thoughtful views. One audience member said traffic tends to even out over time, so intersections that are congested now will not become more congested as the number of vehicles increases. Panelists disagreed, saying that the intersections will become significantly more clogged and, in addition, traffic will increasingly spill over into surrounding residential streets. Another audience member said he believed such congestion just had to be accepted if one lived in a desirable city. Others contested that view, saying that a city with traffic jams, idling cars, and deteriorating air quality would become less desirable to live in. 

City Councilor Ken Reeves asked how the Alliance responded to the view expressed by Barry Bluestone and others that the way to control housing prices was to build more housing. Panelists responded that the arguments of traditional “supply side economics” do not apply here, as even one of the city’s planners said at a recent public meeting; thousands of residents have been driven out of the city by high rents and housing prices in recent years, while development has proceeded apace.    

In closing, members of the Cambridge Residents Alliance noted that the danger of the city’s streets and public transit becoming overwhelmed by excessive development is real. Given this prospect, a one-year moratorium on large up-zoning petitions should be adopted, until the full integrated impacts of the proposed large-scale developments can be assessed.

*Shelley Rieman, a Cambridgeport resident, and Jackie Dee King, an Area 4 resident, are members of the Steering Committee of the Cambridge Residents Alliance.