Horizontal Curve Safety

Horizontal curves are those that change the alignment or direction of the road (as opposed to vertical curves, which change the slope).More than 25 percent of fatal crashes are associated with a horizontal curve, and the vast majority of these crashes are roadway departures. The average crash rate for horizontal curves is about three times that of other types of highway segments. About three-quarters of curve-related fatal crashes involve single vehicles leaving the roadway and striking trees, utility poles, rocks, or other fixed objects—or overturning.

Most roadway departure countermeasures are effective when applied specifically at horizontal curves. A focus on horizontal curves can prove to be a cost-effective approach to reducing roadway departure crashes. Many of these countermeasures are low-cost and can be installed at prioritized horizontal curves to address safety issues.

  • Low-Cost Treatments for Horizontal Curve Safety
    This publication provides practical information about low-cost treatments that can be applied at horizontal curves to address identified or potential safety problems, and includes a description of maintenance activities that should be conducted to maintain countermeasure effectiveness. FHWA-SA-07-002.

  • A Guide for Reducing Collisions on Horizontal Curves
    Volume 7 in a series of National Cooperative Highway Research Program (NCHRP) reports on ways to reduce injuries and fatalities in targeted crash areas, this Guide identifies 20 countermeasures to address specific safety issues at horizontal curves. The guide describes the strategies and provides step-by-step implementation guidance.

  • Skid Accident Reduction Program (T 5040.17)
    This Technical Advisory provides a general overview of factors that should be considered as elements of any Skid Accident Reduction Program.

Program Contact

Cathy Satterfield

708-283-3552

What's New

Sign Retroreflectivity Toolkit

Sign Upgrade Guide Specification

Publications

Low Cost Treatments for Horizontal Curve Safety

Pavement Edge Brochure: The Safety Edge