Public Comment

Commentary: Implement Area-Wide Traffic Calming in 2008

By Michael Jerrett
Tuesday January 15, 2008

Two tragic pedestrian deaths in the past month emphasize how urgently the City of Berkeley needs a new approach to pedestrian safety. This new approach would rely on area-wide traffic calming, paid for by financial charges to drivers. Councilmember Capitelli’s appeal to the moral side of drivers is not enough to improve pedestrian safety in Berkeley.  

Two important points have emerged from many years of study and experience in pedestrian safety: 1) drivers will behave badly if given the opportunity and no appeal to their better side will change this fact, and 2) area-wide traffic calming prevents accidents and saves lives. Mr. Capitelli correctly notes that traffic volume, speed and dangerous driving are on the top of many peoples’ minds in Berkeley. But to assert that he doesn’t actually “think the answer is always a tangible change to the streetscape” defies many years of research.  

Some of the most comprehensive studies to date show that traffic calming in the form of traffic circles and speed humps reduces accidents by between 75 percent-82 percent and even modest measures such as stop signs will reduce accidents by 70 percent. Locally, pediatrician Dr. June Tester published an important paper in 2004 showing that in areas of Oakland with speed humps, traffic injuries to children requiring hospitalization were cut in half compared to other areas without the humps. Internationally, recent studies indicate that countries such as England that have implemented aggressive speed control policies have seen deaths from crashes, including those with pedestrians, drop by 34 percent, while in the United States the equivalent number was only 6.5 percent over the 1990s. Controlling speed with traffic calming saves lives.  

Berkeley was the first city in the United States to implement traffic calming, but it has rested on its laurels for too long now and this has created inequities in safety and quality of life. Some neighborhoods like the wealthy Claremont are fortresses that do not allow cars to traverse anything but main streets. In other neighborhoods, such as the Northside of the UC Berkeley Campus where I live, near Spruce and Virginia, many cars and trucks cut through at high speed with virtual impunity. Similarly Mr. Capitelli’s Thousand Oaks neighborhood is also overrun with traffic, but under-served by traffic calming, and we have just witnessed the horrible consequences that can result from this type of inequity. Much of the inequity has historic roots, when progressive forces in well-organized neighborhoods pushed for changes in the 1980s and 1990s. By the mid-1990s, there was a moratorium placed on speed humps, one of the most cost-effective forms of traffic calming.  

Since then drivers in the city have had the upper hand. The prohibitively high cost of traffic circles (about 5 or more times the cost of speed humps for equivalent safety benefits) left many neighborhoods with virtually no protection. Slowly residents have aligned with the Safe Routes to School movement and others interested in safety and improving physical activity to scratch out minor improvements. There are too many gaps from this ad hoc approach. My own children must walk across Shattuck Avenue at the uncontrolled intersection of Virginia, with over 30,000 vehicles per day passing. A pedestrian was killed there in 2006, but there are still no improvements to pedestrian safety on this unsafe route to school. Drivers on many occasions have challenged my family and others in the cross walk by speeding directly at us and not slowing down until we back away. If drivers cannot muster their best behavior when the lives of little children are in the balance, what can we expect at other intersections such as the one at Marin and Colusa, which has claimed two lives in the past year?  

Fortunately after 14 years without the most cost effective traffic calming tool, the city is now piloting a new version of the speed hump, known as the speed cushion, which allows for better emergency vehicle access. But speed cushions and other traffic calming measures are almost always more likely to land in areas of highly organized or wealthy communities. While the concerns of residents must always play a role in decision-making, more often than not this reactive approach to pedestrian safety only worsens inequalities.  

Rather than approach these problems on a complaint or accident basis, the councilmembers should resolve in 2008 to implement area-wide traffic calming. Area-wide traffic calming would systematically address large sections of the city to ensure that all residents benefited equally, not just those who are wealthy, organized, educated or particularly concerned because they have children. The key to area-wide measures is that they are integrated and will not just push traffic from one street to the next. Instead these measures slow traffic everywhere within a specified zone. The evidence from the academic literature is clear: area-wide traffic calming prevents accidents and saves lives. 

This type of traffic calming will require money, which could be paid for by direct charges on drivers entering sensitive areas of Berkeley. This can be implemented through increased levies on parking, on congestion charges for persons commuting from outside the city, on delivery companies who frequent residential neighborhoods, on additional sales taxes on all goods related to automobiles, and from a variety of other user fees that hit drivers in the pocket book. London, England, has implemented a congestion zone charge that has been effective enough that they are planning to expand the area in the next few years. New York City and San Francisco are considering similar plans. By charging drivers directly, our city can also ensure that commuters and delivery companies who use our streets as a cut-through on their way to employment hubs here pay their fair share, something that for too long has gone as a free ride. When the true costs of driving become apparent to commuters, their incentive to drive alone into Berkeley is reduced. Trucks will see cheaper routes and commuters may take public transit or form car pools.  

There are proven solutions available to Berkeley, but will politicians and city staff resolve to put pedestrian safety first, and move forward to again become a leader in protecting public health from this serious risk?  


Michael Jerrett is associate professor of geographic information science and spatial analysis in UC Berkeley School of Public Health’s Division of Environmental Health Sciences.