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National Highway System (NHS) Freight Connectors

NHS freight connectors are the public roads that connect major intermodal terminals to the highway network. They are critical components of our transportation system and important conduits for the timely and reliable delivery of goods and services. Hence, it is important to evaluate the condition and performance of intermodal connectors and their related investment needs. Highlights of two FHWA studies on the condition of NHS freight connectors and needed improvements are discussed here.[1]

Public roads leading to major intermodal terminals are designated NHS connectors by the U.S. Department of Transportation, in cooperation with state departments of transportation and metropolitan planning organizations (MPOs). Several criteria are considered, including the level of activity of an intermodal terminal and its importance to a state's economy. There are 517 freight-only terminals and 99 major airports that handle both passengers and freight. These 616 intermodal freight terminals are connected to the NHS by 1,222 miles of connectors (Table 1).

Table 1. NHS Connector Mileage
Function Class Mileage
Total Rural and Urban 1,222
Rural 219
Interstate 5
Other principal arterial 32
Minor arterial 57
Major collector 88
Minor collector 7
Local 30
Urbana 1,004
Interstate/Expressway 89
Other principal arterial 438
Minor arterial 294
Collector 117
Local 66

Note: Numbers do not add to total due to rounding.
aUrban encompasses facilities within an FHWA-adjusted Census urbanized area (UA). A UA is an area of 50,000 people or more with a minimum population density. Census UAs are adjusted to include additional areas, such as airports, satellite cities/towns, and strip developments adjacent to high-use roadways, that are important to or serve the urbanized area and, in some cases, land that will become urban in the near future (3-5 years).

Although intermodal connectors account for less than 1 percent of total NHS mileage, they handle large volumes of trucks moving goods between terminals and the NHS or other modes. Intermodal connectors also support defense mobilization and national security. Because of the military's increasing reliance on commercial transportation to move supplies and personnel, intermodal linkages to ports and airports have become an integral part of national defense planning.

NHS freight connectors are typically located in older, industrialized and mixed land use areas that are subject to physical constraints. They usually average less than two miles in length and have lower design standards than mainline NHS routes (primarily Interstates and arterials). FHWA found that freight connectors are in poorer condition than NHS routes, which can slow freight movement, damage goods in transit, decrease efficiency, and negatively affect safety. Specifically, the FHWA's NHS Intermodal Freight Connectors report found:

  • Connectors to marine ports have twice the percentage of mileage with pavement deficiencies compared to non-Interstate routes.
  • Connectors to rail terminals had 50 percent more mileage in the deficient category than non-Interstate routes.
  • Connectors to airport and pipeline terminals appeared to be in better condition, with about the same percentage of mileage with pavement deficiencies as those on non-Interstate NHS routes.
  • The most frequently cited deficiencies were problems with shoulders, inadequate turning radii, and inadequate travel way width.

This 2000 report to Congress, based on an inventory conducted in 1998, did not include an assessment of needed improvements or investment requirements. FHWA initiated a follow-on effort to develop an estimate of investment needs for NHS freight connectors based on identified deficiencies. Table 2 shows connector deficiencies and the type of improvement needed.

Table 2. Deficiencies and Improvements Needed
  Mileage
Identified Deficiency and Improvement Needed Rural Urbana Total
Capacity Needed 39 362 401
Major reconstruction 7 75 82
Major widening 32 287 319
Lane Widening 29 81 110
Minor reconstruction 10 29 39
Minor widening 19 52 71
Pavement Work 114 356 470
Reconstruction 24 46 70
Resurface shoulders 63 159 222
Resurface 27 151 178
No Action Needed 62 181 243

Note: Numbers do not add to 1,222 miles due to rounding.
aSee Table 1 for definition.

The principal findings of the needs analysis are:

  • Nearly one-third of total connector miles were judged to be in need of additional capacity.
  • Approximately 38 percent of connector miles needed pavement work, which includes resurfacing and reconstruction of lanes and shoulders.
  • Only 20 percent of total connector miles were considered to have adequate pavement and lane or shoulder width.
  • A program to eliminate identified deficiencies is estimated to cost more than $2.5 billion (current 1996 $) (Table 3).
  • If a systemic effort were initiated to improve the overall level of service of the NHS connectors, more in accordance with the conditions and service of the mainline NHS routes, then an investment of approximately $4.2 billion (current 1996 $) would be required (Table 4).
  • The cost of improving spot deficiencies would add another $87.1 million (current 1996 $) to the total costs for both estimates.

Table 3. Cost to Eliminate Deficiencies (1996 Current $ Millions)
  Investment Needed
Identified Deficiency and Improvement Needed Rural Urbana Total
Total Costs 141.5 2,368.3 2,509.8
Capacity Needed 112.5 1,979.7 2,092.2
Major reconstruction 18.8 565.2 584.0
Major widening 93.7 1,414.5 1,508.2
Lane Widening 8.7 209.4 218.1
Minor reconstruction 2.6 108.2 110.8
Minor widening 6.1 101.2 107.3
Pavement Work 20.3 179.2 199.5
Reconstruction 6.5 70.5 77.0
Resurface shoulders 10.6 59.9 70.5
Resurface 3.2 48.8 52.0

aSee Table 1 for definition.

Table 4. Cost to Improve Performance Level (1996 Current $ Millions)
Improvements Investment Needed
  Rural Urbana Total
Total Costs 171 4,032 4,203
Capacity Needed 113 2,252 2,365
Lane Widening Needed 7 220 227
Pavement Work Needed 51 1,560 1,611

Note: Numbers do not add to $4,204 million due to rounding.
aSee Table 1 for definition.

There is wide agreement among freight stakeholders that intermodal connectors need to be improved. As with all transportation improvements, funding is a major concern. The issues related to funding NHS connector improvements are similar to those of freight investments in general. States and MPOs, for example, often see intermodal connectors as a low priority when compared to pressing needs of passenger travel. Compounding this issue is the fact that more than half of NHS connector mileage is under local jurisdictional control (Table 5). Localities may not have the money to fund needed improvements, and states may not have the authority to spend funds on local roadways. The result is that intermodal connector needs are not met. Concerns related to intermodal connectors are among the many issues that Congress will consider in its reauthorization of the highway program.

Table 5. NHS Connector Mileage by Jurisdiction
Jurisdiction Mileage Percent
Total 1,222 100
State 349 29
Local 635 52
State and Local 238 19

1U.S. Department of Transportation, Federal Highway Administration, NHS Intermodal Freight Connectors: A Report to Congress (Washington, DC: December 2000); and U.S. Department of Transportation, Federal Highway Administration, 2002 Status of the Nation's Highways, Bridges, and Transit: Condition and Performance (Washington, DC: 2003).

For More Information, Please Contact

Joanne Sedor
Office of Freight Management and Operations
Federal Highway Administration
(202) 366-8959
joanne.sedor@fhwa.dot.gov

June 2003
FHWA-OP-03-088
EDL 13796
Office of Operations