Published: Friday, July 1, 2011, 12:01 a.m.
We've pressed the city of Lynnwood to provide hard data about the reported safety benefits
of traffic-enforcement cameras. Until now, we've received only national statistics cranked out by traffic-camera boosters and budget figures documenting the multimillion-dollar boon
cameras have become to Lynnwood's bottom line
Recently Lynnwood provided its best -- and as near as we can tell only -- analysis of accident data at intersections where cameras are used to issue red-light tickets.
The verdict? There isn't enough information to reach a conclusion on safety, according to Lynnwood police Cmdr. Chuck Steichen, who oversaw the analysis.
"It is difficult to say what the long-term effect of the systems will be given the limited trending data that we have," he said.
Steichen examined accidents at eight intersections where cameras have been installed. In all but one case, the analysis compared two years before and two years after.
The city's numbers suggest 17 fewer collisions at the intersections with cameras. Of the 183 after-camera crashes, 14 fewer involved some sort of injury.
But the same data show crashes were up or stayed the same at about half the intersections studied. Similar uneven results were seen for injury accidents.
Bottom line: It's premature for anyone to say red-light cameras have caused an outbreak of traffic safety in Lynnwood.
The city conducted the analysis after The Herald on May 25 filed a public records request that could have compelled release of about 650 accident reports. Pulling and redacting private information from those records would have been a challenge for the city. We negotiated. Steichen and others offered to assemble their report -- something they didn't strictly have to do under the state's public records laws.
The police commander is quick to acknowledge the limits of the analysis.
Whether the fewer accidents are statistically significant is a big question. There also are several other possible explanations for dips in crashes and injuries, including the economic slowdown. Moreover, the report doesn't address whether crashes are somehow different since cameras came to town. Some studies elsewhere have found more rear-end collisions.
Steichen thinks fewer injury accidents in Lynnwood are cause for cautious optimism.
"That is a promising number," he said. "It is a ray of sunshine if you will, but I don't know what the forecast is for the next three or four years."
The biggest benefit of traffic cameras, he said, is that enforcement is happening consistently at the intersections -- not always a given for Lynnwood, with its continuing budget mess
and shriveling police force.
Collisions by Lynnwood intersection, before and after cameras
Red numbers = accidents with enforcement cameras in place
|196th St SW and Hwy 99||20||21||18||23|| ||0|
|196th St SW and 36th Ave W||9||15||11||14|| ||+1|
|184th St SW and Alderwood Mall Parkway|| ||6||12||12||9||+3|
|200th St SW / 44th Ave W / Alderwood Mall Blvd||10||11||8||14|| ||+1|
|196th St SW and 44th Ave W||20||12||16||10|| ||-6|
|196th St SW and Alderwood Mall Pkwy|| ||22||19||17||15||-9|
|Maple Rd and Alderwood Mall Pkwy|| ||7||10||5||7||-5|
|200th St SW and Hwy 99|| || || ||6||4||-2|
|Overall difference|| || || || || ||-17|
SOURCE: Lynnwood Police Department
Map of Lynnwood traffic camera locationsView Lynnwood traffic enforcement cameras in a larger map