Bumps, humps and now lumps to slow down speeders Bumps, humps and now lumps to slow down speeders (May 28, 2004)

by Jeb Bing

W ith traffic dominating the concerns of many in Pleasanton, it's no surprise that traffic engineers are working overtime in trying to find ways to reduce speeding and traffic volumes on city streets. At last Saturday's Public Works Open House, the traffic information booth and presentations by Traffic Engineer Jeff Knowles and his associate Mike Tassano stole the show, with almost all of the 350 visitors asking about traffic on their own residential streets.

Fortunately, Knowles, who has more than 25 years of traffic engineering and management experience, has assembled a virtual toolbox of systems and devices to tackle many of the problems that have long exasperated police. Pleasanton has six motorcycle traffic cops and its regular shift of neighborhood patrol cars to watch over the tens of thousands of motorists using city streets each week. Chief Tim Neal appreciates any help traffic engineers can provide, and he's already seeing quick and positive results from Knowles' efforts. Take Vineyard Avenue at Montevino, where speeds once pushed 50 mph and more. A new traffic light installed last month uses radar to turn the signal red for Vineyard motorists approaching the light at speeds 3 mph above the posted limits. Drive Vineyard, as I do almost every day, and you'll see motorists driving much slower well before and after the Montevino light, apparently more aware of the speed they're traveling.

Whether it's a traffic circle, roundabout, flashing speed limit light or portable radar units loaned to concerned neighbors, Knowles and Tassano have put into place a citizen complaint and response system that seems to be working. A few months ago, several residents on Crellin Road asked the engineers for help to reduce speeding on that long stretch of roadway that dead ends at Touriga Drive in Vintage Hills and again six blocks east up a hill into the gated community of Gray Eagle. Built exceptionally wide at the upper end to accommodate traffic to a new Vintage Hills elementary school that was never built, Crellin handles only a few hundred cars a day between Gray Eagle, the Foxbrough community and a few streets of homes in between, including mine on Malaga Court. Up where I am, it's a perfect place to speed, and many do. In a radar survey requested by Knowles, police stopped one motorist traveling 53 mph, well above the 25 mph limit. Most speeding vehicles are probably traveling about 35-40, which is clearly too fast when they reach the older, more densely and extra-long single block between Madeira and Touriga, where most of the complaints emanated.

After the radar survey showed excessive speeding, Knowles proposed placing speed lumps on the lower part of Crellin - a new device in his traffic toolbox that he has seen used successfully in Southern California's Thousand Oaks, where he once was a traffic engineer. A less jarring speed control than the speed bumps and humps used mainly in shopping centers, these tapered, three-inch high lumps made out of noiseless recycled tires allow cars to travel across them relatively smoothly at speeds between 23-28 mph. Go faster and you'll likely pop a spring or shock absorber. Where these have been used, including Fremont, they've solved the speeding problem for good, Knowles insists, freeing police to look elsewhere for violators.

Knowles and Tassano are hoping to join Crellin Road residents for an installation block party this summer as the six new 14-foot-wide speed lumps are bolted into the street, providing what the two engineers see as a happy ending to a successful citizen activist process that shows their traffic complaint system works. Of course, success could mean calls from others in town who see speeding motorists on their streets. Knowles' City Hall number, by the way, is 931-5677, or e-mail jknowles@ci.pleasanton.ca.us.

E-mail a friend a link to this story.