High Friction Surface Treatment Curve Selection and Installation Guide May 2016

5. Step 5: Estimate Costs and Identify Funding

This section discusses how to estimate HFST implementation costs and potential means of funding the safety improvement.

5.1. Cost

Costs will fluctuate based on choice of aggregate, binder, and application method. Many agencies can find the lowest unit cost when they are able to get two or more contractors to compete for the project.

On average, the cost breakdown for HFST installation is approximately comprised of 50 percent for labor and application and 50 percent for materials (i.e., aggregate and binder). Of the materials cost, roughly two-thirds of that cost can be attributed to the binder, as approximated in Figure 10.³⁵ Most of the aggregates used for HFST generally range from $350 to $500 per ton.

Figure 10. HFST Cost Breakdown Approximation.

States' HFST unit costs range from $22 to $35 per sq. yd. Typically, unit costs are lower when:

• A large volume of HFST is to be applied at a single location or multiple small installations are bundled into a single contract;
• HFST is only one component of a larger contract; or
• HFST installers directly perform the application rather than hiring a general contractor to then subcontract the work.

Other factors affecting unit cost are the amount of traffic control needed, availability of staging areas, and agency specification requirements.^36,37

Overall, HFST's benefit-cost ratio is high since the crash reductions are typically drastic and continue for many years indicating a positive return on investment for each dollar spent on the treatment. SCDOT found a benefit-cost ratio of about 24 to 1 during a before and after study for a series of HFST curve installations.³⁸

A report commissioned by Transit New Zealand showed a benefit-cost ratio of 40, whereas Virginia Tech Transportation Institute (VTTI) found that HFSTs produce benefit-cost ratios ranging between 2.23 and 8.45.^{39, 40} TTI estimates HFST return on investment to be approximately five-fold if an initial application prevents one fatal or injury crash (valued at over $158,000). If a fatality is averted, the return is over 100 times the amount invested.⁴¹

The exact nature of each particular installation and the problem it addresses will have a direct bearing on the exact benefit-cost ratio that can be achieved, but in general, HFSTs have shown to produce a significant return on investment in a short period of time.

5.2. Funding

HFST qualifies for Federal funding under the Highway Safety Improvement Program (HSIP), which is geared toward reducing crashes, fatalities, and injuries on all public roads. While each State's process varies, local agencies can apply to receive funding for HFST projects within their jurisdiction.

In the past, the Federal Highway Administration (FHWA) has matched HFST project costs through a 90/10 split utilizing funds in the HSIP program. In the future, the Federal government may cover the entire cost.⁴²

PennDOT's HFST projects have been entirely funded through the HSIP program, which allocated $8 million to be spent over two years using the treatment. TDOT primarily utilizes HSIP funds for HFST projects, and supplements with 23 U.S.C. 154 Open Container funds, to cover 100 percent of project costs. Caltrans has completed and/or planned approximately 139 HFST projects on their State highway system using HSIP funding, with an additional 30 to 40 completed and/or planned on the local system.