In Step 3 of the Residential Traffic Calming Program procedures, the Traffic Engineering Division uses the data collected in Step 2 to assign a "priority" to a given traffic calming request. With this priority, the request goes onto the Residential Area Traffic Calming Priority Listing, with higher-priority requests receiving attention first. Seven factors go into calculating the priority, producing a total score in a range from 0 to 105 points:

Traffic Volumes

Few very high-volume streets are likely to qualify for traffic calming; these streets tend to be major thoroughfares -- and we are not permitted to traffic-calm major thoroughfares.

Speeds

Points = 85th percentile speed (mph) - 25 mph. 

The "85th percentile speed" is the speed at or below which 85% of the street's traffic is observed to be traveling. If 85% of traffic on a street is observed to be traveling at or below 43 mph, then 43 mph is the 85th percentile speed. In this case the number of points assigned in the "speed" category would be 43 - 25, or 18 points. 

Not to exceed 20 points

Accidents

Number of mid-block accidents over a 3-year period, divided by 3, divided by the roadway length in miles. (The term "mid-block accidents" is very important; accidents at intersections are not counted.)

For instance, assume a street 1.25 miles in length has had 15 mid-block accidents over the last three years. 15 divided by 3 is 5 average annual accidents, which when divided by 1.25 miles results in 4 "average annual accident rate/mile." This would in turn result in assigning 20 points to this street, in this category.

Schools

Each school within 1 mile of impact area is 5 points. Not to exceed 10 points.  If there are more than two schools within 1 mile of impact area, the extras are added to "Other pedestrian generators" (below).

Other Pedestrian Generators

5 points per pedestrian generator, including extra schools, parks, and playgrounds. Not to exceed 10 points.

No Sidewalk

No sidewalk: 10 points. Sidewalk on one or both sides: 0 points.

Density

Calculated by dividing the number of residential units fronting the roadway by the length of the roadway in miles.