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State Safety Initiative Database

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Natural Bridge Avenue Safety Project

Missouri

The Natural Bridge Ave road diet and safety project reduced speeds by 17%, reduced all crashes by 75% and fatal pedestrian crashes by 100%.

Project Webpage AASHTO Case Study

J-Turns Analysis

Missouri

J-turns reduced fatal and injury crashes by 54% and right-angle crashes by 80%.

Missouri J-Turns Webpage University of Missouri Article AASHTO Case Study

Lane Constrictor Intersection Statewide Implementation

Minnesota

Lane constrictor intersections reduced fatal and injury crashes in Minnesota by 20%.

Traffic Safety Evaluation of Lane Constrictors Report TRB Project Page AASHTO Case Study

J-Turn Statewide Implementation

Minnesota

J-turn intersections reduced angle crashes by 67% and fatal and serious injury angle crashes by 87%.

Minnesota J-Turn Webpage J-Turn Driver Tutorial AASHTO Case Study

MD 187 (Old Georgetown Road) Quick Build Lane Reallocation to Address Bicyclist Safety

Maryland

Lane reallocation for new bicycle lanes on MD 187 reduced bicyclist fatal and injury crashes, and improved safety for vulnerable road users.

Community Meeting Presentation Project Announcement Report to General Assembly AASHTO Case Study

Examining the Impact of Centerline Rumble Strips on Reducing Rural Two-Lane Head-On Collisions in Maine

Maine

Centerline rumble strips reduced head-on and opposite sideswipe collisions by 28-48%.

Research Paper Rumble Strips Brochure AASHTO Case Study

Idaho’s US-20 Expansion from SH-55 to Locust Grove

Idaho

US-20 expansion and reflective backplating on signals reduced serious injury and fatal crashes by 75%.

Project Overview Flyer AASHTO Case Study

Reconstruction, Widening, and Signalization at the Intersection of West Karcher Road (SH-55) and Lake Avenue