Office of Operations Freight Management and Operations

Freight Intermodal Connectors Study

Chapter 6. Summary of Key Findings and Options for Future Research

This chapter describes key conclusions related to freight intermodal connectors. The key conclusions are grouped into the following categories:

  • Designating freight intermodal connectors.
  • Characteristics and use of freight intermodal connectors.
  • Condition and performance of freight intermodal connectors.
  • Data availability for freight intermodal connectors.
  • Planning for freight intermodal connectors.
  • Funding for freight intermodal connectors.

This chapter concludes with options to consider for future research into freight intermodal connectors. Most of these options for future research include identifying applications for the findings that were made throughout conducting the study.

Key Findings on Designation of Freight Intermodal Connectors

There are 798 designated National Highway System (NHS) freight intermodal connectors. The number of intermodal connectors has increased by 30 percent since the initial NHS designation. The number of port and rail connectors is likely to continue to increase as freight and supply chain trends indicate a continued increase in usage of intermodal containers for these modes.

Port intermodal connectors are the most common type of intermodal connector representing 40 percent of all freight intermodal connectors. Rail, airport, and pipeline intermodal connectors represent 26 percent, 26 percent, and 7 percent of freight intermodal connectors, respectively.

Designation of connectors has not kept pace with facts on the ground. There are some functionally obsolete and lightly traveled connectors that are still designated as critical NHS connectors. There are also some new, heavily used connectors that have not yet been added.

Truck-truck terminals share many of the same characteristics as designated NHS freight terminals. Truck-truck terminals often attract large volumes of trucks to lesser used and local roads. Goods are stored, transloaded and reloaded back into trailers for delivery to final destinations. Many of these truck-truck terminals are co-located with rail intermodal facilities. However, many of the trucks that access the truck-truck terminals do not utilize the rail facilities. Additionally, they often utilize different access roads compared to trucks that are accessing the rail facilities.

Key Findings on Characteristics and Use of Freight Intermodal Connectors

There are approximately 1,484 miles of designated NHS freight intermodal connectors. The vast majority of freight intermodal connectors have relatively low capacity. Roughly half of the connectors are just two lanes, while roadways with three or four lanes represent another 40 percent of the total freight intermodal connectors.

Most freight intermodal connectors are relatively short with an average length of 0.98 miles. The distribution of connector lengths is skewed such that there are a small number of very relatively long connectors and 71 percent of the connectors are less than one mile in length.

Fifty-four percent of the freight intermodal connectors are owned by a city or municipal level highway agency. These connectors tend to be rather short with an average length of 0.68 miles. Twenty-nine percent of the freight intermodal connectors are owned by State highway agencies. These connectors have the highest average length of all ownership categories at 1.66 miles.

Many shippers and truckers perceive freight connectors as the entire roadway path between terminal gate and nearest Interstate highway. The current definition of connectors as the only link between the gate and the nearest NHS roadway (often a two- or four-lane State or local roadway that falls well short of Interstate standards) is inconsistent with the shipper and trucker perspective.

There were approximately 1,368,219 truck miles traveled on freight intermodal connectors in 2013. Over 1.2 million of these miles occurred in urbanized areas. Average truck volumes on freight intermodal connectors are 762 trucks per day. Airport intermodal connectors have the highest amounts of use in terms of both total vehicle volume and truck volume.

There are a small number of intermodal connectors that are carrying the bulk of the intermodal truck Vehicle Miles Traveled (VMT). Nearly half of all of the intermodal truck VMT occurs on the top five percent of freight intermodal connectors in terms of volume. Ninety-seven percent of the truck VMT is captured on the top 50 percent of connectors.

While principal arterials (other) represent just 21 percent of all freight intermodal connectors, they carry roughly half of the truck VMT on freight intermodal connectors. This is in part due to the longer lengths of principal arterials and to their higher volumes.

State highway agencies are the owners of just 29 percent of the freight intermodal connectors. However connectors owned by State agencies carry 59 percent of the total connector truck VMT. The reverse is true for city or municipal highway agencies. They own 54 percent of intermodal connectors, but carry just 29 percent of connector truck VMT.

Key Findings on Condition and Performance of Freight Intermodal Connectors

The Highway Performance Monitoring System (HPMS) includes International Roughness Index (IRI) pavement condition readings at 1,239 locations across the 798 designated freight intermodal connectors. The average IRI value for all of these readings is 211, which rates as mediocre. Thirty-seven percent of the connectors rate as poor. Another 54 percent rate as either mediocre or fair. Only nine percent have a good or very good pavement condition.

Average IRI values for connectors owned by State highway agencies is 154 (fair) compared to an average value of 257 (poor) for city or municipal highway agencies. Combined with other findings, this reveals that there are two primary types of connectors:

  • Short, low-volume connectors owned by cities or municipal agencies with poor pavement condition.
  • Relatively long, high-volume connectors owned by State highway agencies with fair pavement condition.

Airport intermodal connectors have an IRI value of 155 (fair) which is significantly lower than the other freight modes, which are all on average rated as mediocre or poor. The higher pavement quality of airport connectors may be a result of fewer large trucks and/or better inclusion in the planning process.

It is estimated that between $30.8 million and $335.2 million in annual additional vehicle operating costs from connectors that do not have good pavement condition. This wide range of estimates indicates that there is the need for additional research on the full impacts of pavement condition on truck activity.

Average nighttime truck speeds (considered to be free-flow speeds) on rural connectors is 42 mi/h, much higher than the 28 mi/h average free-flow speed on urban connectors. There is notable congestion on freight intermodal connectors with daytime speeds consistently lower than free-flow speeds. On average, truck speeds drop on average 11 percent between free-flow and daytime speeds. Urban rail and port connectors have some of the most significant congestion issues with respective 21 percent and 14 percent speed drops between free-flow conditions and slowest daytime conditions.

Average truck speeds generally decrease as pavement conditions worsen. However, the average amount of congestion on a roadway did not increase for worse pavement condition. Additionally, there was not found to be a relationship between truck volumes and congestion, so connectors with low truck volumes are as likely to suffer from congestion as high truck volume connectors. In total, an estimated 4,237 hours of truck delay occur on freight intermodal connectors every day. Using the HERS-ST value of delay factors, this is equivalent to $353 million of annual additional costs for truck movements on connectors.

Key Findings on Data Availability for Freight Intermodal Connectors

The HPMS database includes truck volume estimates on 88 percent of all designated NHS intermodal connectors and pavement condition estimates on 82 percent of the connectors. The NPMRDS database includes speed data on 52 percent of the connectors. These percentages are large enough to allow for generalizations to be made about the use, condition and performance of connectors. However, efforts to improve data availability will improve the usefulness of these databases in planning for a wider set of connectors.

Reporting to HPMS on conditions and performance of individual connectors is lagging. This is primarily due to the HPMS database not being designed to provide estimates on individual local roads with the type of unique characteristics that are featured on freight intermodal connectors. The inability of the HPMS to fully capture the conditions and performance of freight connectors affects assessments of national needs. Additionally, new truck speed and travel time data provide valuable insights into performance of connectors, but these are not currently incorporated into the HPMS. There is also a need for a closer linkage between GIS maps of networks, including connectors, and the HPMS database to allow information to move seamlessly across various platforms that include different types of data on freight connectors.

The most important data element to improve in terms of accuracy is truck volume data. To ensure accurate representation of freight activity, it is recommended that truck count data be collected on every freight intermodal connector every three to five years. Additionally, truck count data should include counts of both single-unit and combination vehicles. There are two options to consider in regards to improving State reporting of data on freight intermodal connectors:

  1. Make increased data collection on connectors a requirement for continued inclusion in the designated freight intermodal connector program.
  2. Make increased data collection on connectors a requirement for HPMS.

To balance the increased costs associated with counting truck volumes on freight intermodal connectors, allowances should be made to allow partial day counts, as long as the majority of the freight facility operating hours are captured in the data collection, and reasonable expansion factors are identified.

Another option that could balance the increased cost of a more detailed data collection on freight intermodal connectors is to reduce the number of roadways that qualify for designation into the freight intermodal program. Additionally, there should be consideration of removing roadways from the program when their volumes decrease beyond a certain level. It is interesting to note that, based on HPMS truck volume data, 198 of the designated freight intermodal connectors have volumes under 100 trucks per day, indicating that they would not qualify for the program if the application was occurring today.

An additional rationale for reducing the number of connectors in the program is evident in the distribution of truck volumes across the roadways. As noted in the Task 5 report, the highest 50 percent connectors in terms of VMT carry 97 percent of the total truck VMT. It would be reasonable to limit the designated NHS freight intermodal connector program to the top 50 percent of connectors in terms of VMT, because it would still capture the vast majority of truck VMT that occurs on connectors. A smaller number of freight intermodal connectors is also more consistent with the FHWA current tracking of speeds on intermodal connectors using the NPMRDS data, which focuses on just 43 miles of connectors compared to the 1,484 miles of designated NHS freight intermodal connectors.

A reduced number of designated freight intermodal connectors would also make it easier to improve and maintain data for several elements other than truck volumes. Additional improvements that could be made to the database include:

  • Linking truck-involved crash data on the connector.
  • Adding information on the number of trains, trucks and autos that are currently at railroad-grade crossings.
  • Linking of roadway network identification between HPMS and NPMRDS for improved speed data conflation.

An alternative to reducing the number of designated freight intermodal connectors is to develop a two-tiered system, where connectors with volumes below a certain threshold are tracked using the current system, while connectors above the threshold are required to include more detail performance and activity data.

Key Conclusions Related to Planning for Freight Intermodal Connectors

Planning for connectors is very uneven. Considerable number of State Departments of Transportation (DOTs) and metropolitan planning organizations (MPOs) do not include connectors in regional models or truck route networks. Moreover, it is difficult for State DOTs and MPOs to forecast volumes of truck trip generated by terminals because current and future demand are often determined by economic conditions, business competition factors, and unforeseen technology developments.

There is a failure on the part of both the public and private sector to tell the story of intermodal connectors as critical links in freight transportation supply chains serving local economies and national and global markets. The conditions and performance of connectors are not measured as part of a freight path and network, are therefore not perceived as contributing to the economy, and consequently do not receive attention and funding.

The case studies revealed that freight intermodal connectors are often not specifically addressed in planning documents. Even freight plans do not systematically incorporate information on use, condition, and performance of freight intermodal connectors. Typically, in locations where freight intermodal connectors are incorporated into the planning process, it is the result of a freight champion that is aware of the importance of connectors, experienced in the transportation planning process, and has strong relationships within the private sector freight community.

There is sufficient data on freight intermodal connectors that can be readily incorporated into freight planning and general planning documents. Specifically, there is information on pavement condition and vehicle speeds that are generally available and reasonably accurate to describe the condition and performance of freight intermodal connectors. Additionally, information on crossings and bridge condition are available and can be incorporated as well. Truck and auto volume data are also available through the HPMS database, but should be verified by facility operators or through supplemental counts to improve the accuracy of this data.

The verification of connector volumes can be part of the broader outreach effort that is typically incorporated into planning efforts. The outreach should also include a qualitative description of the importance of each of the designated freight intermodal connectors along with documenting if there are designated connectors that are no longer used or new connectors that should be considered for designation. Issues related to uses near connectors should also be documented, including encroachment, right-of-way preservation, and truck and non-truck volumes generated by new uses located along the connectors.

Key Findings on Costs to Improve Connectors and Funding for Improvements to Freight Intermodal Connectors

It is estimated that the cost to improve pavement conditions on freight intermodal connectors to good quality condition is $2.2 billion. To increase capacity on congested connectors and to eliminate truck delays would cost an estimated $3.2 billion. This is exclusive of right-of-way costs that are relatively high in many urban areas where congestion is typically at its worst.

State and local funding sources targeted towards freight intermodal connectors are scarce. During the case study process, Florida was the only State identified as having a funded and active freight intermodal connector program. Typically, funds for connector improvements come from a combination of Federal, State, and facility operator funding sources that are general to transportation improvement.

There are a number of Federal transportation funding programs that can be used for freight intermodal connector improvements. The Fixing America's Surface Transportation (FAST) Act was signed into law in December 2015 and includes a number of provisions focused on ensuring the safe, efficient, and reliable movement of freight. The FAST Act establishes a new National Highway Freight Program to improve the efficient movement of freight on the National Highway Freight Network (NHFN) and supports several goals. Specifically, the FAST Act:

  • Establishes a National Multimodal Freight Policy that includes national goals to guide decision-making.
  • Requires the development of a National Freight Strategic Plan to implement the goals of the new National Multimodal Freight Policy.
  • Creates a new discretionary freight-focused grant program that will invest $4.5 billion over five years. This program allows State, Metropolitan Planning Organizations (MPO), local governments, tribal governments, special purpose districts and public authorities (including port authorities), and other parties to apply for funding to complete projects that improve safety and hold the greatest promise to eliminate freight bottlenecks and improve critical freight movements.
  • Establishes a National Highway Freight Program that provides $6.3 billion in formula funds over five years for States to invest in freight projects on the National Highway Freight Network. Up to 10 percent of these funds may be used for intermodal projects.

Freight intermodal connectors can also be funded and financed through the Federal programs available to all NHS roadways. (Refer to the report Task 2—Data and Literature Search, Review, and Synthesis for a more in depth and detailed discussion of these programs as they relate to intermodal connectors.) Specifically, the Federal funding programs, including the total funding allocated for fiscal year (FY) 2016 to FY 2020, available for freight intermodal connectors include:

  • National Highway Performance Program (NHPP)—Provides $117.5 billion in Federal support for the condition, performance, and construction of the NHS.
  • National Highway Freight Program (NHFP)—New $6.3 billion of formula funding from the FAST Act to improve the National Highway Freight Network (NHFN), which includes the primary highway freight network from MAP-21, critical rural and urban freight corridors, and the remaining Interstate highway system.
  • Nationally Significant Freight and Highway Projects—New $4.5 billion grant program from the FAST Act, administered under Fostering Advancements in Shipping and Transportation for the Long-term Achievement of National Efficiencies (FASTLANE) grants, dedicated towards freight or highway projects of national or regional significance.
  • Surface Transportation Block Grant Program (STBG)—Previously known as the Surface Transportation Program, STBG provides $58.268 billion in flexible funding that may be used to preserve and improve the conditions and performance on any Federal-aid highway, bridge and tunnel projects on any public road, pedestrian and bicycle infrastructure, transit capital projects, and freight projects.
  • Highway Safety Improvement Program (HSIP)—$11.586 billion towards achieving a significant reduction in traffic fatalities and serious injuries on public roads, including non-State owned public roads and roads on tribal lands.
  • Congestion Mitigation and Air Quality Improvement Program (CMAQ)—$12.02 billion funding source to reduce congestion and improve air quality. Available to State and local governments for transportation projects in non-attainment and maintenance areas.
  • U.S. Economic Development Administration (EDA) grants—Funding available to develop infrastructure, including intermodal connector roads in economically distressed areas.

There also are several Federal financing tools that can be applied to freight intermodal connectors. These tools include:

  • Transportation Infrastructure Finance and Innovation Act (TIFIA)—Originally established under MAP-21 and reauthorized under FAST Act, TIFIA provides financial assistance for projects to leverage Federal funds. This includes secured (direct) loans with flexible repayment terms, loan guarantees, and standby lines of credit as a secondary source of funding. Any project eligible for Federal assistance through existing surface transportation programs is eligible for the TIFIA program, including intermodal freight transfer facilities or projects that provide access to such facilities.
  • Grant Anticipation Revenue Vehicles (GARVEE)—Established under MAP-21, GARVEE is a financing instrument that allows States to issue debt backed by future Federal-aid highway revenues. Eligibility for freight projects is constrained by the underlying Federal-aid programs that will be used for debt service.

The Appendix provides specific examples of how funding has worked for specific freight intermodal connector improvement projects.

Options for Future Research for Freight Intermodal Connectors

There are several future research options to consider in regards to transforming the findings of this study into implementable recommendations that improve the tracking and performance of freight intermodal connectors. These options can be considered in the following five categories:

  1. Consider changes to the criteria used to designate roadways as freight intermodal connectors.
  2. Create a long-term data program for managing information related to designated NHS Freight intermodal connectors.
  3. Identify options that will improve the quality and amount of data available for planning on freight intermodal connectors.
  4. Generate recommendations for improving the performance tracking of freight intermodal connectors.
  5. Develop guidance for systematically incorporating freight intermodal connectors into typical plans and programs that include freight elements.

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