A new California law allows local governments to consider neighborhood quality and pedestrian safety when setting speed limits.

Formerly, the so-called 85th percentile rule was the primary factor on which speed limits were based. The 85th percentile speed is the speed at or below which 85 percent of motorists drive on any given road. The theory behind the 85th percentile guideline is that most drivers will take road conditions into account and choose a reasonably safe speed.

"As traffic engineers themselves freely admit, the flaw in the 85th percentile approach is that drivers are traveling at a speed they feel is safe for themselves," writes Dani Weber in the Spinning Crank, the Silicon Valley Bicycle Coalition's newsletter.

"That speed is not necessarily safe for other road users like pedestrians and bicyclists. High speeds (over 25 mph) are directly correlated with motorists' failure to yield to pedestrians in cross- walks, high injury rates, injury severity, lack of perceived walkability, and high noise levels. "

The bill, sponsored by Assembly member Hannah-Beth Jackson (D-Santa Barbara), authorizes local authorities to "consider residential density [and] pedestrian and bicyclist safety" when conducting engineering and traffic surveys.

However, real change will only happen if local governments choose make use of the new latitude in setting speed limits. If you think the Santa Cruz Traffic Engineering Department should consider the safety of all road users when setting speed limits, click here to send them a message.