Evaluation of Low-Cost Safety Improvements Pooled Fund Study

Progress Report

September, 2007

The goal of this research is to develop reliable estimates of the safety effectiveness of safety improvements identified as strategies in the National Cooperative Highway Research Program (NCHRP) Report 500 Guidebooks through scientifically rigorous before-after evaluations of sites within the U.S. where these strategies are being implemented.

A target of 20 strategies totaling $4.38 million over 3 to 5 years is planned for ELCSI-PFS studies in four phases. The progress (as of the September, 2007) for each phase is stated below.

Phase I - Retrospective Evaluation

Evaluations include following strategies:

1) STOP Signs with Increased Retroreflectivity,

2) Flashing Beacons,

3) STOP AHEAD Pavement Markings, and

4) Two-Way Left-Turn Lanes.

Status: The Phase I evaluations are completed and are in the review process by the TAC members for final approval. These studies are scheduled to be published by February of 2008.

Phase II - Retrospective Evaluation

Evaluations include following strategies:

1) Offset Left-Turn Lanes,

2) Advance Street Name Signing,

3) Combinations of Shoulder and Centerline Rumble Strips/Stripes, and

4) Lane Width/Shoulder Width Combinations.

Status: At present the Phase II evaluations are ongoing. These evaluations are expected to be completed and published by September of 2008.

Phase III - Prospective Evaluations

In the annual TAC Meeting, 2007, a set of strategies were selected by the TAC members (please see the result of the balloting in the "Phase I-III Balloting" site on the main page.)

Status: At present these strategies are in the process of evaluation for feasibility. The final list of the selected strategies will be announced by the November of 2007.

Phase IV - Simulation

Evaluations the following strategies:

1) Enhanced shoulder or in-lane delineation and marking for sharp curves,

2) Enhanced pavement markings,

3) Enhanced delineation along the curve,

4) Advanced warning of unexpected changes in horizontal alignment, and

5) Dynamic curve warning system.

Status: Work plans are in the design stage for evaluations by the FHWA's Driving Simulation Lab (considering feasibility) for the above. The simulations are expected to be completed by the June of 2009.