Removing Lines as a Traffic Calming Measure: Data, anyone?
Reader Bob Widlansky, from Wilmette, Illinois, writes in regarding a problem on his street that is perhaps the most universal complaint in the world of traffic: Drivers going too fast on residential streets.
As he notes, “I live on a very wide street [pictured above] residential built in the early 1900’s to accommodate a street-car line that used to run down the middle. In an effort to slow down traffic on my residential street, the Village has painted edge-lines and a yellow centerline. The majority of residents believe this has actually increased traffic speeds.”
He has begun pushing the idea (rather unsuccessfully — the city engineer cites safety concerns) at local meetings to remove the center lines, a concept that I describe in Traffic, based on some research done by the TRL and demonstrated in some rural English towns — where it was found that removing the center-lines not only reduced speeds, it led drivers to put more distance between themselves and the opposing stream of traffic. The theory is that lines reduce vigilance, reduce thinking, and potentially increase speeds.
Bob is very passionate about the subject. He’s looking for any data/experience/case studies, preferably from the U.S., where striping and lines were beneficially removed. He’s actually already located some guidance, from the city of Pasadena’s rulebook. He notes that page 22, from the official policy on “Markings/Striping Changes — Removal of Centerline on Residential Streets,” states:
“Centerlines can provide drivers with clear delineation of travelways. On residential local streets that are relatively narrow (36′-42′) with low traffic volumes, centerlines may induce speeding because drivers’ travelways are clearly delineated. Experience has shown that the removal of centerlines on local streets results in more cautious driving behavior. Painted edgelines have a similar effect. Edgelines visually reduce the width of the roadway causing drivers to be more aware.”
I thought I’d open this to the audience: Can anyone help out Bob with studies (before/after observational would be best here, I’d imagine), or have you successfully had lines removed? Or is this even the right way to go about this? Do you have any other suggestions for calming Greenleaf Avenue? Judging by the photo, there are already parked cars, and interestingly, there’s already a sort of differential pavement treatment, a bit confusing to my eyes but apparently not to speeding drivers. What else can be done?
This entry was posted on Thursday, February 12th, 2009 at 1:36 pm and is filed under Etc., Traffic Engineering. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.