The Importance 

of Highways to 

U.S. Agriculture

December 2020

Executive Summary

United States Department of Agriculture
2 Executive Summary The Importance of Highways to U.S. Agriculture

ABOUT THIS REPORT

Agricultural commodities are among the Nation’s largest and most important exports. 

The agriculture industry is the largest user of highway freight, and the industry relies 

on highway infrastructure for the safe and efficient transportation of goods.

This report offers insights to inform the transportation planning and project selection 

processes that build and maintain highway infrastructure used by the agriculture 

industry. The report introduces novel analysis techniques that illuminate how 

domestic agricultural commodities move on U.S. highways, and how the condition 

and performance of those highways may affect the movement of agricultural goods. 

Economic modeling described in the report highlights the potential for increased 

highway investment to benefit the agriculture industry by lowering truck operating 

costs and supporting improved highway performance. The report demonstrates 

the interconnected nature of agricultural freight, and highlights the importance of 

cooperation across State and jurisdictional boundaries.

This report includes:

● A summary of the economic significance of highway transportation to the 

agriculture industry;

● Identification of High-Volume Domestic Agriculture Highways (HDAH) based on 

2018 commodity flows;

● Analysis of the performance of the HDAH and selected corridors within it;

● Modeled projections of future highway freight conditions and performance, 

based on planned investment levels and alternative scenarios;

● Case studies of State and local transportation agencies addressing the highway 

infrastructure needs of the agriculture industry; and

● A framework for conceptualizing and coordinating efforts to better address 

agricultural freight movement in highway planning and decision making. 

Highlights of Research 

Findings:

● 80% of domestic agricultural highway 

freight volume moves on 17% of 

highway mileage.

● State-planned highway freight 

investments are estimated to produce 

$540 million per year in truck 

operating cost savings.

● Increased highway infrastructure 

investment, at a level 2-4 times 

current State Freight Plan investment 

levels, is modeled to be highly costeffective (Benefit/Cost Ratio >2.0). 

Read the full report: 

http://dx.doi.org/10.9752/TS295.12-2020

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Who Should Read This Report?

This report contains valuable information for 

transportation and agriculture industry stakeholders 

alike.

State Departments of Transportation 

(State DOTs) will find information about 

how agricultural commodities flow through 

corridors within their own States and 

neighboring States; they will also find notable 

practices demonstrating opportunities 

to incorporate agricultural data and 

considerations into planning and decisionmaking processes. 

Local Public Agencies (LPAs) 

will find information highlighting the 

importance of local and county roads 

in supporting a global supply chain for 

agricultural products, and strategies for 

overcoming funding, data, and coordination 

barriers.

Agricultural freight shippers and 

carriers will find examples of the valuable 

role their perspective and knowledge can play 

in highway infrastructure planning.

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The Importance of Highways to U.S. Agriculture Executive Summary 3
4 Executive Summary The Importance of Highways to U.S. Agriculture

 U.S. AGRICULTURAL FREIGHT BY THE NUMBERS1

1 All statistics are from Volpe Center analysis of Freight Analysis Framework version 4.5.1 (Bureau of Transportation Statistics (BTS) and Federal Highway Administration (FHWA), 2019).

$3.1 Trillion Annual value of agricultural freight moved across all modes in the 

United States in 2018.

4.5 Billion Annual tonnage of agricultural freight moved across all modes in 

the United States in 2018.

27% Agriculture industry’s share of all freight ton-miles moved.

16% Agriculture industry’s share of all freight by market value.

23% Projected increase in total freight volumes over the next 20 years.

Highways

83% Percentage of all agricultural freight tonnage moved via the 

highway system in 2018.

56% Share of agricultural freight ton-miles moved by truck in 2018.
The Importance of Highways to U.S. Agriculture Executive Summary 5

Trucks move more agricultural freight than any other 

transportation mode.

Almost every agricultural freight trip includes at least one movement by truck in the full 

journey from farm to final destination. 

Figure 1: Modal Transportation Characteristics of Agricultural Commodities by Tonnage, 2018 

Figure 1: Truck is the most common 

transportation mode for agricultural 

commodities. This is particularly true for 

Meat, Poultry, Fish, Seafood, and Live 

Animals and Fish. However, trucks carry 

more than 50% of the tonnage of all 

agricultural commodity categories. 

0% 20% 40% 60% 80% 100%

Newsprint/Paper

Logs

Paper or Paperboard Articles

Wood Products

Fertilizers

Animal Feed and Products

Tobacco Products

Alcoholic Beverages/Denatured Alcohol

Other Prepared (Fats and Oils)

Milled Grain and Bakery Products

Other Agricultural Products

Animals and Fish (Live)

Meat, Poultry, Fish, Seafood

Cereal Grains (includes seed)

Truck Rail Water Air (include truck-air) Pipeline Multiple Modes/Other

Note: Commodity categories based on Standard Classification of Transported Goods (SCTG) commodity 

codes. “Other Agricultural Products” includes soybeans and other oilseeds, vegetables, fruits and nuts, 

and fresh-cut flowers and plants. 

Source: Volpe Center analysis of Freight Analysis Framework v4.5.1 (BTS and FHWA, 2019)
6 Executive Summary The Importance of Highways to U.S. Agriculture

Trucks are an important part of almost every agricultural freight journey.

Trucks may move agricultural goods for an entire journey, through several intermediary steps, or as a part of a multimodal trip that 

includes rail or barge segments. 

Figure 2: U.S. Agricultural Supply Chain for Raw and Processed Products 

Source

Inland Terminal/Hub

Storage

Processing Plant

Intermediary

(May move between one 

or more intermediary steps 

before arriving at destination.)

Export Port

Domestic Use

 Destination

Elevator

Rail

Barge

Truck

KEY

Source: Graphic adapted from “U.S. Agricultural Supply Chain for Raw and Processed Products.” Study of Rural Transportation Issues (USDA, 2010)
Investment in highway infrastructure 

is critical to maintaining economic 

competitiveness.

Low transportation costs is one way that the U.S. agriculture 

industry has remained competitive with low-wage international 

competitors who have lower costs of production. Maintaining 

the performance of highways, which are often the most 

expensive leg of the journey on a per ton-mile basis, is essential 

to keeping freight costs low and supporting producers operating 

under tight profit margins. Should transportation costs increase, 

the United States could lose this competitive advantage, 

particularly if other countries continue to lower transportation 

costs by improving their infrastructure.

Figure 3: Transportation Costs as a Percentage of Overall 

Agricultural Costs 

Freight Costs: 3-4%

Source: A Revised and Expanded Food Dollar Series: A Better 

Understanding of our Food Costs (Canning, P., 2011)

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The Importance of Highways to U.S. Agriculture Executive Summary 7
8 Executive Summary The Importance of Highways to U.S. Agriculture

Low transportation costs help U.S. agriculture remain competitive 

on the global market, but others are catching up.

The example of U.S. and Brazil soybean transportation costs shows that as Brazil’s 

transportation costs have decreased, the United States’ cost advantage has eroded 

significantly.

Figure 4: U.S. and Brazil Soybean Total Transportation Costs to Shanghai, China

40

60

80

100

120

140

160

180

200

Q1Q2Q3Q4Q1Q2Q3Q4Q1Q2Q3Q4Q1Q2Q3Q4Q1Q2Q3Q4Q1Q2Q3Q4Q1Q2Q3Q4Q1Q2Q3Q4Q1Q2Q3Q4

2010 2011 2012 2013 2014 2015 2016 2017 2018

U.S. $/metric ton

Year

Santos Paranagua U.S. Gulf U.S. Pacific Northwest

Note: U.S. Gulf: From Minneapolis, MN, through the U.S. Gulf Coast; U.S. Pacific Northwest: From Fargo, 

ND, through the Pacific Northwest; Santos: From South Goiás, Brazil, data not available for 2018; 

Paranaguá: From North Mato Grosso, Brazil.

Source: Soybean Transportation Guide: Brazil Archive Reports (USDA, n.d.)

2013: Brazil overtook the United States as 

the largest exporter of soybeans.

2014: Total transportation costs for 

soybean shipments from Brazil dropped 

and began to track close to or below U.S. 

costs.
The Importance of Highways to U.S. Agriculture Executive Summary 9

STAKEHOLDER PERSPECTIVES ON AGRICULTURAL 

FREIGHT

• Continued investment in highway infrastructure is needed to maintain 

or improve freight performance. 

• Decentralized local decision making is a barrier for agriculture industry 

stakeholders to communicate challenges and needs.

• Data gaps for rural roads and intermodal transfers limit transportation 

agencies’ ability to understand how products move from farm to 

market.

• Building resiliency and redundancy in highway infrastructure is a 

critical issue.

• Developing State Freight Plans haS encouraged State DOTs to think 

more deeply about highway freight performance.

• State DOTs study agricultural freight via corridor studies.

Stakeholder Input provided by:

The Agricultural Transportation 

Working Group (ATWG): which is 

comprised of a wide variety of food and 

agriculture industry groups representing 

agricultural shippers and receivers;

Six State Departments of 

Transportation (State DOTs): California 

DOT (Caltrans), Iowa DOT (Iowa DOT), 

Missouri DOT (MoDOT), North Carolina 

DOT (NCDOT), Texas DOT (TXDOT), 

and the Washington State DOT 

(WSDOT);

The St. Louis Regional Freightway: a 

regional freight planning organization, 

part of the Bi-State Development 

Corporation of Missouri and Illinois; and

The National Association of Counties 

(NACo). 
10 Executive Summary The Importance of Highways to U.S. Agriculture

80% of domestic agricultural highway freight 

volume moves on 17% of highway mileage

Figure 5: High-Volume Domestic Agricultural Highways (HDAH)

Source: Volpe Center analysis of 2018 IHS Markit Transearch data

Figure 5: This report identifies High-Volume 

Domestic Agriculture Highways (HDAH), 

based on a modeled sample of detailed 

2018 agricultural commodity movements. 

These highways are among the most 

important to the movement of domestic 

agricultural commodities.
Analyses in this report are 

based on a representative 

sample of agricultural 

commodities.

The six major categories of 

commodities used to identify the 

HDAH are: 

Grains

(corn, soybeans, and

wheat)

Fruits and 

Vegetables

(apples, strawberries, oranges,

watermelons, lettuce, dry

onions, and potatoes)

Milk and Dairy 

Products

Meat

(Fresh or frozen Beef, 

Pork, and Poultry)

Livestock

(cows and hogs)

Poultry

(chicken and turkey)

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The Importance of Highways to U.S. Agriculture Executive Summary 11
12 Executive Summary The Importance of Highways to U.S. Agriculture

Highways move agricultural commodities all over the country. 

Agriculture is produced in virtually all States, and the HDAH include highways that connect 

high-producing agricultural areas with storage, processors, ports, other transportation modes, 

and more. The agricultural commodity flows along the HDAH comprise approximately 805 

million tons and represent over $428 billion in market value.

Figure 6: Map of HDAH overlaid with county-level production of selected commodities

Source: Volpe Center analysis of 2017 Census of Agriculture and 2018 IHS Markit Transearch data

1 dot = 1,000 Acres of Fruits & Vegetables Harvested

1 dot = 20,000 Acres of Grain Harvested

1 dot = 3,000 Heads of Dairy Cows

1 dot = 75,000 Heads of Livestock

1 dot = 400,000 Heads of Poultry

 High-Volume Domestic Agricultural Highways

Legend

Figure 6 shows that HDAH connect areas 

where key agricultural products are 

produced in high volumes, based on 2017 

production. 
The Importance of Highways to U.S. Agriculture Executive Summary 13

High-Volume Domestic Agricultural Highways include more than Interstates and the National 

Highway System.

The HDAH consist of over 49,000 highway miles, and include both major and minor highways. They overlap significantly (but not entirely) 

with the National Highway System (NHS), demonstrating that some of the roads that carry the highest volumes of agricultural freight are 

more minor highways.

Figure 7: Percentage of HDAH Mileage On and Off the Interstate System 

50.4%

49.6%

Interstate Non-Interstate

Figure 8: Percentage of HDAH Mileage On and Off the NHS

88.2%

11.8%

NHS Non-NHS

Source: Volpe Center analysis of 2018 Highway Performance Monitoring System data
14 Executive Summary The Importance of Highways to U.S. Agriculture

Combining highway performance and agricultural freight flow data supports investment decision 

making.

The report demonstrates a novel approach to analyzing freight commodity flows and highway infrastructure performance, yielding new 

insights to inform highway investment priorities. It provides a model that may be applied by State DOTs and local transportation agencies to 

other corridors and at different scales. This approach draws largely from public datasets.

Seventeen analysis corridors within the HDAH were studied in detail to help illustrate how specific agricultural commodities move 

through important areas of the highway network. The report includes individual profiles describing the congestion, reliability, and safety 

performance characteristics of each of these corridors, including data visualizations for how these characteristics change throughout.

Figure 9: Analysis Corridor 

Data Charts Example

Source: 

Volpe Center

Example of the corridor data 

charts in Appendix B.

Context map of the corridor 

oriented horizontally to 

relate to the strip chart data 

locations on the corridor.

The first page of each 

corridor data chart includes 

strip charts showing 

data about the physical 

infrastructure conditions 

and performance of the 

corridor.

Individual pages showing 

movement of agricultural 

commodities by Tonnage, 

Market Value, and Truck 

Units.
The Importance of Highways to U.S. Agriculture Executive Summary 15

State DOTs are planning highway projects that improve freight 

performance.

The projects that State DOTs include in their State Freight Plans (SFPs) will have a significant 

impact on freight performance.

Figure 10: State Freight Plan Investments, 2016-2020, by Project Type and HERS Modeling 

Capability (Millions $)

Note: NHFP figures listed include total project costs of NHFP-funded projects, which are made up of

NHFP dollars, State matching funds, and other Federal funds. Appendix C includes information on 

the methodology. 

Source: Volpe Center analysis of 51 State Freight Plans as published in December 2019

● $17 billion of National Highway Freight

Program (NHFP) funding and $10.6

billion of other funding sources were

programmed in SFP projects between

Fiscal Years 2016-2020. 24% of these

SFP projects were planned on the

HDAH.

● Modeling with the Highway Economic

Requirements System (HERS) suggests

that projects of this type and at this

level of investment will produce

nearly $540 million per year in truck

operating cost savings relative to a

baseline in which these investments

are not made.
16 Executive Summary The Importance of Highways to U.S. Agriculture

Economic modeling highlights the potential benefits of additional 

investment in highway infrastructure.

The Federal Highway Administration’s Highway Economic Requirements System (HERS) model 

was used to estimate the impacts of alternative scenarios for highway investment. Investment 

levels of twice and four times the current level in State Freight Plans were found to be costeffective, with modeled incremental benefits exceeding incremental costs by a factor of 2 or 

more. The expanded benefits include avoided crashes, reduced congestion, and savings in 

vehicle operating costs.

Figure 11: Benefits and Costs (in Billion $)

$280 $299 $318 $356

$1,398 $1,439 $1,477 $1,549

 $-

 $200

 $400

 $600

 $800

 $1,000

 $1,200

 $1,400

 $1,600

Baseline State Freight

Plans

2x Investment

Scenario

4x Investment

Scenario

Total Cost of Initial Improvements ($B) Total Benefits ($B over 5-year period)

Source: Volpe Center analysis using HERS Model and State Freight Plans

● Modeled cost-effectiveness declines 

only slightly even if investment levels 

were doubled or quadrupled from 

the levels in the State Freight Plans, 

suggesting that many worthy projects 

could be funded if investment levels 

increase.

● HERS model outputs should be viewed 

as estimates of national-level impacts, 

rather than impacts for any individual 

project or sector.
The Importance of Highways to U.S. Agriculture Executive Summary 17

Case studies of notable practices in freight planning and analysis 

demonstrate a range of innovations agencies are using.

State DOTs, regional planning agencies, and their local partners have developed innovative

approaches to filling freight data gaps, engaging freight stakeholders, and analyzing the

performance of the highway freight system to improve highway networks and multimodal 

connections in their jurisdictions.

Many of the practices highlighted in these case studies apply to highway freight generally.

However, each case study also includes a description of the potential impacts that are specific

to agricultural freight.

Table 1: Freight Planning and Analysis Case Studies 

Freight Planning and Analysis Topic Agency

1 Cross-Department Coordination for Improved 

Agricultural Freight Infrastructure

Missouri Department of 

Transportation

2 Advanced Freight Networks and Data Systems Washington State Department 

of Transportation

3 State Grant Programs to Enhance Multimodal 

Freight Connectivity 

Iowa Department of 

Transportation and others

4 Prioritizing Freight Projects with Data-Driven 

Methods and Tools 

Iowa Department of 

Transportation

5 Collaborative Freight Project Identification and 

Prioritization 

St. Louis Regional 

Freightway

6 State Freight Advisory Committees Texas Department of 

Transportation

Source: Volpe Center
18 Executive Summary The Importance of Highways to U.S. Agriculture

Challenges, Opportunities, and Strategies for 

Improvement

Agricultural highway freight is a complex system. In order to maintain or improve the system, 

many different types of stakeholders must work together, including State DOTs, Federal 

agencies, agriculture producers and shippers, and freight carriers.

This report synthesizes research, analysis, and stakeholder input to identify 10 challenges 

and opportunities, and suggests potential strategies to address them.

Agricultural 

Freight Data

1. Improving Data on Agricultural Freight Movements

2. Understanding and Communicating Seasonal Effects on 

Demand and Performance

3. Improving and Standardizing Freight Data and Analysis Tools

Freight Planning 

and Analysis

4. Enhancing Corridor Analyses to Identify Agricultural Freight 

Performance Challenges

5. Accessing Local and Industry Knowledge to Inform Infrastructure 

Planning

6. Analyzing Performance in the Context of National and 

International Supply Chains

7. Identifying Redundant Routes to Avoid Disruptions

Project 

Identification 

and 

Prioritization

8. Addressing County and Local Infrastructure Condition

9. Optimizing Highway Investment Decision-Making to Benefit 

Freight Supply Chains

10. Cooperating Across Jurisdictions in Planning and Project 

Development
The efficient movement of 

agricultural commodities is 

important to the continued health, 

prosperity, and economy of the 

United States. 

As the U.S. population continues to 

grow and our economy continues 

to evolve, freight volumes are 

forecast to grow by nearly 25% over 

20 years. Continued investment in 

highways that support the movement 

of agricultural freight during this 

period of growth will be critical to the 

health and competitiveness of U.S. 

agriculture.

This report provides a piece of a 

larger puzzle in understanding the 

complex multimodal system that 

moves agricultural commodities 

across the country, emphasizing 

the importance of highways to U.S. 

agriculture.

Read the full report: 

http://dx.doi.org/10.9752/TS295.12-2020

The Importance of Highways to U.S. Agriculture Executive Summary 19

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Executive Summary

The Importance of Highways to U.S. Agriculture

http://dx.doi.org/10.9752/TS300.12-2020