Conditions and Performance Report

Conditions and Performance Report
Chapter 7—Future Capital Investment Requirements

Conditions and Performance Chapter Listing

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Introduction

Summary

Economics-Based Approach to Transportation Investments

Highway Investment Requirements

Bridge Investment Requirements

Combined Highway and Bridge Investment Requirements

Transit Investment Requirements

Cost to Maintain Highways and Bridges

Combining the Highway Maintain Conditions scenario with the Bridge Maintain Backlog scenario results in a combined average annual Cost to Maintain Highways and Bridges of $56.6 billion. This total is broken down by functional class in Exhibit 7-10. The investment requirements are classified into three categories, system preservation, system expansion, and system enhancement. System Preservation consists of the investment required to preserve and maintain the pavement and bridge infra-structure. This includes the costs of resurfacing, rehabilitation, and reconstruction. System Expansion includes the costs related to adding lanes to existing facilities, or adding new roads and bridges. System Enhancements include safety enhancements, traffic operations improvements, and environmental improvements.

The investment requirements for urban arterials and collectors total $27.4 billion or 48.3 percent of the average annual Cost to Maintain Highways and Bridges. Investment requirements for rural arterials and collectors total $18.5 billion (32.7 percent), while the investment requirements for rural and urban local roads and streets total $10.8 billion (19.0 percent).

Exhibit 7-10. Average Annual Investment Required to Maintain Highways and Bridges


Q How were the investment requirements identified by HERS split between system preservation and system expansion?
A All improvements selected by HERS that did not add lanes to a facility were classified as system preservation. For improvements that added lanes, the total cost of the improvement was split between these two categories, since widening projects typically improve the existing lanes of a facility to some degree when adding new ones. Also, adding new lanes to a facility tends to reduce the amount of traffic carried by each of the old lanes, which may extend their pavement life. To classify these improvements, the HERS analysis for this scenario was rerun with a constraint added to prevent the model from adding any lanes. The difference between these two runs was taken to be the amount attributable solely to system expansion. HERS does not currently identify investment requirements for system enhancements.

System Preservation

Average annual system preservation investment requirements total $31.8 billion, comprising 56.1 percent of the total Cost to Maintain High-ways and Bridges. As shown in Exhibit 7-11, system preservation makes up a much larger share of total investment requirements in rural areas than in urban areas.

Exhibit 7-11

1998-2017 Cost to Maintain Highways and Bridges, Distribution By Improvement Type

The system preservation investment requirements are derived primarily from the HERS and BNIP models. An adjustment was made to the highway figures, to account for rural minor collectors and local functional class roads which are not included in the HPMS sample section database on which HERS relies.


Q Would it be necessary to invest the full amount identified as the Cost to Maintain Highways and Bridges, in order to maintain average pavement condition and the backlog of bridge deficiencies?
A No. The $56.6 billion average annual amount specified includes a mix of improvements designed to attain the highest possible level of benefits, including some improvements that do not address the physical conditions of highways and bridges. If all investment requirements for system expansion and system enhancements were ignored, an average annual investment of $31.8 billion of system preservation investment would be sufficient to maintain physical conditions. However, if total highway and bridge capital investment were limited to $31.8 billion annually, the analytical procedures used in this report would suggest that it would be more cost beneficial to split this amount among system preservation, system expansion, and system enhancements, rather than use it all for system preservation.

System Expansion

The $20.3 billion in average annual investment requirements for system expansion represents 35.9 percent of the total Cost to Maintain Highways and Bridges. This includes investment requirements derived from HERS for widening existing highways and bridges. External adjustments were applied to cover types of investment that HERS does not consider, the widening of rural minor collectors and local functional class roads, and the construction of new roads and bridges.

System Enhancements

The $4.5 billion in average annual investment requirements for system enhancements represents 8.0 percent of the total Cost to Maintain Highways and Bridges. Investment requirements for safety enhancements, traffic operation facilities, and environmental enhancements are not directly modeled, so this amount was derived solely from the external adjustment procedures described earlier. Long range plans for the HERS model include expanding its scope to consider some of the ITS and safety improvements included under system enhancements.


Q Can highway capacity be expanded without adding new lanes or new roads and bridges?
A Yes. Highway capacity can be increased by improving the utilization of the existing infrastructure. In many cases, increased investment in intelligent transportation systems may be more cost beneficial than building new roads, double decking roads, or adding new lanes in high cost urban areas. (See the discussion of High-cost lanes in Appendix G). Some of the investment requirements identified as for "System Expansion" could also be met through increased investment in types of "System Enhancements" that also increase capacity.

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Page last modified on November 7, 2014