Diagonal diverters are barriers placed diagonally across an intersection, blocking through movements and creating two separate, L-shaped streets. Like half closures, diagonal diverters are often staggered to create circuitous routes through the neighborhood as a whole, discouraging non-local traffic while maintaining access for local residents. They are good for inner-neighborhood locations with non-local traffic volume problems.

Advantages:

• Diagonal Diverters do not require a closure per se, only a redirection of existing streets
• They are able to maintain full pedestrian and bicycle access
• They reduce traffic volumes

Disadvantages:

• They cause circuitous routes for local residents and emergency services
• They may be expensive
• They may require reconstruction of corner curbs

Effectiveness:

• Average of 35% decrease in traffic volume, or a decrease of 501 vehicles per day (from a sample of 27 sites)

Similar Measures:

• By placing a barrier across a street along only one stem of the intersection, you have a Full Closure
• By placing a barrier only half-way across a street along only one stem of the intersection, you have a Half Closure
• By placing the barrier length-wise along the roadway centerline across a side street, you have a Median Barrier

Cost Estimate(s):

• $85,000 (Seattle, WA)