U.S. Department of Transportation
Federal Highway Administration
1200 New Jersey Avenue, SE
Washington, DC 20590
202-366-4000
1997 Federal Highway Cost
Allocation Study
Final Report
U.S. Department of Transportation
Federal Highway Administration
Executive Summary | ES-1 | |
Study Objectives and Scope | ES-1 | |
Summary of Highway Cost Allocation Study Methods | ES-1 | |
Vehicle Travel Characteristics and Population by Different Vehicle Classes | ES-2 | |
2000 Federal-aid Highway Program Costs | ES-2 | |
Allocation of 2000 Federal Highway Program Costs | ES-3 | |
Life Cycle Cost Analysis | ES-5 | |
Estimates of 2000 Federal Highway User Revenues | ES-5 | |
2000 Federal Highway User Charge Equity Ratios | ES-6 | |
Highway Cost Allocation for All Levels of Government | ES-8 | |
Other Highway-Related Costs | ES-9 | |
Marginal Highway Costs | ES-10 | |
Total Costs of Highways | ES-10 | |
Potential User Fee Changes to Improve Equity | ES-11 | |
Study Conclusions | ES-13 |
I. Study Background, Objectives, Scope, and Approach | I-1 | |
Background | I-1 | |
What Is Highway Cost Allocation? | I-1 | |
Recent Studies Related to Highway Cost Allocation | I-3 | |
1982 Federal Highway Cost Allocation Study | I-3 | |
Alternatives to Tax on Use of Heavy Trucks | I-5 | |
Heavy Vehicle Cost Responsibility Study | I-5 | |
Feasibility of a Federal Weight Distance Tax | I-6 | |
Trucking Research Institute Review of Highway Cost Allocation | I-7 | |
1997 Federal Highway Cost Allocation Study Outreach | I-7 | |
Highway Cost Allocation Study Issues | I-8 | |
Relationship Between the Federal Highway Cost Allocation and Comprehensive Truck Size and Weight Studies | I-10 | |
External and Other Non-Agency Costs | I-11 | |
Study Objectives and Scope | I-13 | |
Summary of Study Approach and Methods | I-14 |
II. Trends and Forecasts of Highway Use | II-1 | |
Vehicle Classes | II-1 | |
Base and Future Year Vehicle Stock | II-2 | |
Vehicle Population By Weight Groups | II-3 | |
Base Year and Future Year Highway Travel | II-3 | |
Relationship Between Operating and Registered Weights | II-8 |
III. Trends and Forecasts of Highway Costs | III-1 | |
Introduction | III-1 | |
Base Period Highway Program Costs | III-3 | |
Federal Highway Program Costs and the Fiscal Management Information System | III-3 | |
Obligation of Federal Funds for Highway-Related Improvements | III-4 | |
Detailed Work Types | III-6 | |
Life Cycle Cost Analysis | III-6 | |
Federal Obligations for Transit | III-9 | |
Future Federal Highway Program Costs | III-9 | |
State and Local Highway Program Costs | III-10 | |
Forecast of Future State and Local Highway Program Financing | III-11 | |
Forecast of State and Local Highway Expenditures | III-11 | |
Non-Agency Costs Associated With Highway Transportation | III-12 | |
Air Pollution | III-14 | |
Noise | III-15 | |
Greenhouse Gas Emissions | III-16 | |
Congestion | III-16 | |
Crash Costs | III-18 | |
Water Quality | III-19 | |
Waste Disposal | III-20 | |
Vibration Effects on Structures | III-20 | |
Aesthetic Impacts of Highways | III-20 | |
Effects of Roads as Barriers | III-20 | |
Loss of Parklands and Natural Habitats | III-20 | |
Environmental Impacts During Construction | III-21 | |
More Controversial Impacts Sometimes Attributed To Highways and Highway Use | III-21 |
IV. Trends and Forecasts of Highway User Revenues | IV-1 | |
What Are Highway User Charges? | IV-1 | |
Treatment of Fees Used for Non-Highway Purposes | IV-3 | |
Current Federal Revenue Sources | IV-4 | |
Motor Fuel Taxes | IV-4 | |
Other Federal Highway Taxes | IV-5 | |
Exemptions from the Federal Taxes | IV-6 | |
Categories of Exempt Users | IV-8 | |
Current and Forecast Federal Highway User Revenues | IV-11 | |
State and Local Revenues | IV-13 | |
Highway Finance Data Sources | IV-14 | |
Comparison of Highway User Revenue Data | IV-16 | |
Trends in Motor Fuel Tax Rates | IV-17 | |
Trends in Motor Vehicle Fees for State and Local Governments | IV-17 | |
Highway User Revenues Collected By All Levels of Government | IV-18 | |
Revenues Per Vehicle Miles of Travel and Per Registered Vehicle | IV-18 | |
Highway User Revenues Collected By All Levels of Government | IV-19 | |
Comparison of User Payments by Vehicle Class for all Levels of Government | IV-19 | |
Federal Highway Taxes Paid by Different Vehicle Classes | IV-22 | |
Fuel Taxes | IV-22 | |
Truck and Trailer Excise Tax | IV-22 | |
Tire Tax | IV-22 | |
Heavy Vehicle Use Tax | IV-23 |
V. Highway Cost Responsibility | V-1 | |
Cost Occasioned Approach | V-1 | |
Basis and Philosophy | V-1 | |
Federal Agency Cost Allocation | V-4 | |
Pavement Cost Allocation Methods | V-5 | |
New Pavement, Added Lanes | V-5 | |
Pavement Preservation Costs | V-10 | |
Bridge Cost Allocation Methods | V-13 | |
New Bridges | V-13 | |
Bridge Replacement | V-15 | |
Major Bridge Rehabilitation | V-16 | |
Other Bridge Improvements | V-16 | |
System Enhancements | V-17 | |
Uniquely Occasioned Costs | V-18 | |
Other Highway Trust Fund Obligations | V-19 | |
Mass Transit Account | V-19 | |
Summary of Federal Agency Cost Allocation | V-20 | |
Registered Weight Federal Cost Responsibilities | V-21 | |
All Levels of Government Cost Allocation | V-22 | |
Allocation of External and Other Social Costs of Highway Use | V-23 | |
Noise | V-23 | |
Congestion | V-24 | |
Crash Costs | V-25 | |
Responsibility for Social Costs | V-27 |
VI. Equity and Efficiency of Highway User Fees | VI-1 | |
Comparison of Federal Revenues and Occasioned Costs | VI-1 | |
Effects of Alternative Investment Patterns | VI-9 | |
Federal User Fee Options to Improve Equity | VI-11 | |
Comparison of Tax Structures for All Levels of Government | VI-19 | |
Consideration of Social Costs of Highway Use in Assessing Federal User Fee Equity and Efficiency | VI-22 | |
Summary | VI-30 |
VII. Study Conclusions | VII-1 |
Table ES-1. |
2000 Travel and Number of Vehicles by Vehicle Class |
ES-2 |
Table ES-2. | Ratios of 2000 Federal User Charges to Allocated Costs by Vehicle Class | ES-6 |
Table ES-3. | 2000 Federal Over and Underpayments by 20 Vehicle Classes | ES-7 |
Table ES-4. | 2000 Federal Over and Underpayment by Selected Vehicles | ES-8 |
Table ES-5. | Ratios of 2000 User Fee Payments to Allocated Costs for All Levels of Government | ES-9 |
Table ES-6. | 2000 Marginal Pavement, Congestion, Crash, Air Pollution, and Noise Costs for Illustrative Vehicles Under Specific Conditions | ES-11 |
Table ES-7. | 2000 Ratios of User Changes to Allocated Costs by Vehicle Class Under Alternative Federal User Charge Structures | ES-12 |
Table ES-8. | Summary of Key Findings in the 1997 Federal HCAS | ES-15 |
Table I-1. | HCAS Vehicle Class Categories | I-15 |
Table II-1. | Number of Vehicles by Vehicle Class for 1994 and 2000 | II-3 |
Table II-2. | 1994 Number of Vehicles by Vehicle Class and Registered Weight | II-5 |
Table II-3. | 2000 Number of Vehicles by Vehicle Class and Registered Weight | II-5 |
Table II-4. | Highway Functional Classes | II-6 |
Table II-5. | 1994 VMT by Vehicle Class and Highway Functional Class | II-9 |
Table II-6. | 2000 VMT by Vehicle Class and Highway Functional Class | II-10 |
Table II-7. | 1994 VMT by Operating Weight Group | II-11 |
Table II-8. | 2000 VMT by Operating Weight Group | II-12 |
Table II-9. | 1994 VMT by Vehicle Class and Registered Weight | II-13 |
Table II-10. | 2000 VMT by Vehicle Class and Registered Weight | II-14 |
Table II-11. | Trends and Projections of VMT by Vehicle Class | II-15 |
Table III-1. | Total Federal, State, and Local Highway Expenditures--1985-1994 | III-3 |
Table III-2. | Comparison of Pre-ISTEA (1990) and ISTEA (1993-1995) Period Federal Highway Obligations by Improvement Type | III-4 |
Table III-3. | Base Period Federal Highway Program Costs by Highway Functional Class | III-5 |
Table III-4. | Base Period Obligations for Selected Work Types | III-6 |
Table III-5. | Base Period (1993-1995) Federal Highway Program Obligations by Improvement Type and Highway Functional Class | III-7 |
Table III-6. | 1994 Federal Obligations for Transit | III-9 |
Table III-7. | Estimated Distribution of Federal Highway Obligations in 2000 | III-10 |
Table III-8. | Highway Obligations or Expenditures for 1994 and 2000 for All Levels of Government | III-12 |
Table III-9. | High, Middle, and Low Assumptions Used in Estimating Noise Costs | III-15 |
Table III-10. | Noise Costs in the Year 2000 | III-15 |
Table III-11. | High, Middle, and Low Assumptions Used in Estimating Congestion Costs | III-17 |
Table III-12. | Congestion Costs in the Year 2000 | III-17 |
Table III-13. | High, Middle, and Low Assumptions Used in Estimating Crash Costs | III-18 |
Table III-14. | Crash Costs in the Year 2000 | III-19 |
Table III-15. | Estimate of Waste Disposal Costs | III-20 |
Table IV-1. | Comparison of Overall National HURs and Obligations or Expenditures for All Levels of Government for 1994 and 2000 | IV-2 |
Table IV-2. | Distribution of Federal Highway Motor Fuel Taxes | IV-6 |
Table IV-3. | Current Federal Tax Rate | IV-7 |
Table IV-4. | Estimated Value of Federal HTF Exemptions for 1994 and 2000 | IV-11 |
Table IV-5. | Federal Highway User Fee Payments by Vehicle Class -- 1994 | IV-13 |
Table IV-6. | Federal Highway User Fee Payments by Vehicle Class -- 2000 | IV-14 |
Table IV-7. | State and Local HURs for 1994 and 2000 | IV-15 |
Table IV-8. | Total 1994 HURs for All Levels of Government | IV-19 |
Table IV-9. | Total 2000 HURs for All Levels of Government | IV-20 |
Table IV-10. | 1994 HURs by Type for All Levels of Government | IV-20 |
Table IV-11. | 2000 Highway User Fee Payments by Vehicle Class for All Levels of Government | IV-21 |
Table V-1. | Major Federal Cost Categories for Cost Allocation | V-5 |
Table V-2. | 2000 Allocatable Federal Costs for New Pavement Construction | V-5 |
Table V-3. | Proportion of Federal New Pavement Costs Attributable to the Base Facility | V-6 |
Table V-4. | 2000 Federal New Pavement Cost Responsibility for Selected Vehicles | V-7 |
Table V-5. | 2000 Federal Cost Responsibility for New Pavement Improvements | V-8 |
Table V-6. | 2000 Federal Cost Responsibility for New Pavement Costs for Selected Vehicle Classes | V-9 |
Table V-7. | 2000 Allocatable Costs for Pavement Preservation | V-10 |
Table V-8. | 2000 Proportion of Federal 3R Pavement Costs Attributable to Non-Load Factors | V-11 |
Table V-9. | 2000 Federal Cost Responsibility for 3R Pavement Improvements | V-12 |
Table V-10. | 2000 Federal Cost Responsibility for Pavement 3R Costs for Selected Vehicle Classes | V-12 |
Table V-11. | 2000 Allocatable Federal Costs for Bridge Cost Allocation | V-13 |
Table V-12. | Summary of Improvements to Structures Cost Allocation Procedures | V-14 |
Table V-13. | Structures Design Increments | V-15 |
Table V-14. | 2000 Federal Bridge Costs by Vehicle Class and Improvement Type | V-16 |
Table V-15. | 2000 Federal Cost Responsibility for All Bridge Costs | V-17 |
Table V-16. | 2000 Federal Distribution of System Enhancements Costs | V-18 |
Table V-17. | 2000 Federal Cost Responsibility for Safety and TSM Improvements | V-18 |
Table V-18. | 2000 Allocation of Federal Highway Program Costs Among Broad Vehicle Classes | V-20 |
Table V-19. | 2000 Comparison of Federal Cost Responsibility on Registered Weight and Operating Weight Basis | V-22 |
Table V-20. | 2000 Federal Cost Responsibility on a Registered Weight Basis for Selected Vehicles | V-23 |
Table V-21. | 2000 Federal Cost Responsibility for All Levels of Government by Vehicle Class | V-23 |
Table V-22. | 2000 Marginal External Costs for Noise | V-24 |
Table V-23. | 2000 Marginal External Costs for Congestion | V-25 |
Table V-24. | 2000 Marginal External Costs for Crashes | V-26 |
Table V-25. | 2000 Responsibility for Social Costs of Highway Use | V-27 |
Table V-26. | 2000 Marginal Pavement, Congestion, Crash and Noise Costs for Illustrative Vehicles Under Specific Conditions | V-28 |
Table V-27. | Illustrative Marginal Congestion Costs on 4-Lane Urban Interstates | V-29 |
Table VI-1. | Base Period and Forecast Period Equity Ratios for Broad Vehicle Classes | VI-2 |
Table VI-2. | Comparison of Equity Ratios Based on Registered Weights and Operating Weights of Different Vehicle Classes | VI-3 |
Table VI-3. | 2000 Federal Equity Ratios for Single Unit Trucks Based on Registered Weights | VI-4 |
Table VI-4. | 2000 Federal Over and Underpayment by Single Unit Trucks at Different Registered Weights | VI-5 |
Table VI-5. | 2000 Federal Equity Ratios for Selected Vehicle Classes Based on Registered Weights | VI-7 |
Table VI-6. | 2000 Federal Over and Underpayment by 5- and 6-axle Combination Vehicles | VI-8 |
Table VI-7. | 2000 Federal Over and Underpayments by 20 Vehicle Classes | VI-8 |
Table VI-8. | Distribution of 2000 Federal Obligations by Improvement Category | VI-9 |
Table VI-9. | Shares of Cost Responsibility for Different Improvement Types | VI-9 |
Table VI-10. | 2000 Federal Cost Responsibility For Different Highway Cost Improvement Categories | VI-10 |
Table VI-11. | Distributions of Federal Obligations Under Alternative 2000 Investment Scenarios | VI-11 |
Table VI-12. | 2000 Federal Equity Ratios Under Alternative Investment Scenarios | VI-11 |
Table VI-13. | Current and Illustrative Federal User Fee Rates | VI-12 |
Table VI-14. | 2000 Ratios of User Charges to Allocated Costs by Vehicle Class Under Alternative Federal User Charge Structures | VI-13 |
Table VI-15. | 2000 Ratios of User Charges to Allocated Costs by Vehicle Class Under Alternative Federal User Charge Structures | VI-14 |
Table VI-16. | Illustrative Annual HVUT Rates for Scenario 4 | VI-15 |
Table VI-17. | Federal HVUT Payments by Vehicles With Different Annual Mileages | VI-15 |
Table VI-18. | Illustrative WDT Rate Structure Under Scenario 5 | VI-18 |
Table VI-19. | Illustrative Axle WDT Rates Under Scenario 6 | VI-19 |
Table VI-20. | 2000 Ratios of User Charges to Allocated Costs by Vehicle Class Under Alternative Federal User Charge Structures | VI-20 |
Table VI-21. | Ratios of 2000 User Fee Payments to Allocated Costs for All Levels of Government | VI-21 |
Table VI-22. | 2000 Comparison of Assumed Federal Share of Marginal Highway Costs to Federal Agency Costs and Federal User Fees | VI-23 |
Table VI-23. | 2000 Responsibility for Social Costs of Highway Use | VI-27 |
Figure ES-1. | 2000 Distribution of Federal Highway-Related Obligations by Function | ES-3 |
Figure ES-2. | 2000 Distribution of Federal Obligations by Location and Highway Type | ES-3 |
Figure ES-3. | Distribution of 2000 Federal Program Cost Responsibility Among Vehicle Classes | ES-4 |
Figure ES-4. | 2000 Federal User Fee Distribution by Vehicle Class | ES-5 |
Figure ES-5. | Comparison of 2000 Equity Ratios for 1982 and 1997 Federal HCASs | ES-7 |
Figure I-1. | Graphical Illustration of HCAS Vehicle Classes | I-16 |
Figure II-1. | 2000 Operating Weight Distributions for Single Unit Trucks | II-4 |
Figure II-2. | 2000 Operating Weight Distributions for Selected Combination Trucks | II-4 |
Figure II-3. | 2000 Operating Weight Distributions for Selected Multi-trailer Truck Types | II-4 |
Figure II-4. | 2000 VMT Distribution by Highway Functional Class | II-6 |
Figure II-5. | Travel by Different Vehicle Classes on Different Highway Types | II-7 |
Figure II-6. | 2000 Operating Weight Distributions for Selected Truck Types | II-7 |
Figure II-7. | Comparison of Operating vs. Registered Weight for 3-axle Single Unit Trucks | II-15 |
Figure II-8. | Comparison of Operating vs. Registered Weight for 5-axle Tractor-Semitrailer | II-16 |
Figure II-9. | Comparison of Operating and Registered Weight Distributions for 8+ axle Twin-Trailer Combinations | II-16 |
Figure II-10. | Operating Weight Distributions of 3-axle Single Unit Trucks Registered at 35,000, 45,000 and 55,000 pounds | II-17 |
Figure II-11. | Operating Weight Distributions of 5-axle Tractor-Semitrailers Registered at 65,000, 80,000 and 90,000 pounds | II-17 |
Figure II-12. | Operating Weight Distributions of 8+ axle Twin-Trailer Combinations Registered at 110,000, 120,000 and 130,000 pounds | II-18 |
Figure III-1. | 1994 Source of Funds for State and Local Highway Programs | III-3 |
Figure III-2. | Distribution of ISTEA-Period Obligations | III-5 |
Figure III-3. | Distribution of Base Period Costs by Highway Class | III-6 |
Figure III-4. | LCCA Results Expressed as Cost Savings | III-8 |
Figure III-5. | Savings Due to Varying Rehabilitation Threshold | III-9 |
Figure IV-1. | 2000 Distribution of Federal Highway Revenues by Broad Vehicle Classes | IV-12 |
Figure IV-2. | 2000 Distribution of Federal Highway User Tax Categories | IV-12 |
Figure IV-3. | State Government HURs 1980-1994 | IV-16 |
Figure IV-4. | Local Government HURs 1980-1994 | IV-16 |
Figure IV-5. | Federal and State Motor Fuel Tax Rates | IV-17 |
Figure IV-6. | State and Local Motor Vehicle Fees Per Registered Vehicle 1980-1994 | IV-18 |
Figure IV-7. | Federal, State, and Local Revenues, 1980-1994 | IV-18 |
Figure IV-8. | HURs for All Levels of Government Per VMT and Per Registered Vehicle, 1980-1994 | IV-19 |
Figure IV-9. | Federal Taxes for 5-axle Tractor-Semitrailer Combination by Registered Weight | IV-22 |
Figure V-1. | 2000 New Pavement Cost Responsibility Distribution | V-7 |
Figure V-2. | 2000 New Pavement Cost Responsibility Distribution by Broad Vehicle Classes | V-9 |
Figure V-3. | 2000 Federal 3R Cost Responsibility Distribution by Broad Vehicle Classes | V-13 |
Figure V-4. | 2000 Distribution of Federal Highway Programs by Broad Vehicle Classes | V-20 |
Figure V-5. | 2000 Distribution of Federal Costs by Operating Weight for Single Unit Trucks | V-21 |
Figure V-6. | 2000 Distribution of Federal Costs by Operating Weight for Single Trailer Combinations | V-21 |
Figure V-7. | 2000 Distribution of Federal Costs by Operating Weight for Multi-Trailer Combinations | V-21 |
Figure V-8. | 2000 Distribution of Noise Costs (Middle Estimate) by Broad Vehicle Classes | V-24 |
Figure V-9. | 2000 Distribution of Congestion Costs (Middle Estimate) by Broad Vehicle Classes | V-25 |
Figure VI-1. | 2000 Federal Overpayment and Underpayment per Vehicle for Single Unit Trucks | VI-5 |
Figure VI-2. | 2000 Overpayments and Underpayments per Vehicle by Selected Combination Vehicles | VI-6 |
Figure VI-3. | 3-axle Single Unit Trucks Revenues and Cost Responsibility | VI-16 |
Figure VI-4. | 3-axle Single Unit Trucks Revenues and Cost Responsibility | VI-16 |
Figure VI-5. | 5-axle Tractor-SemiTrailer Revenues and Cost Responsibility | VI-16 |
Figure VI-6. | 5-axle Tractor-Semitrailer Revenues and Cost Responsibility | VI-16 |
Figure VI-7. | Effects of Additional 1 Cent and 6 Cent Differential -- 3-axle Single Unit Trucks | VI-16 |
Figure VI-8. | Effects of Additional 1 Cent and 6 Cent Diesel Differential -- 5-axle Tractor-Semitrailer | VI-16 |
Figure VI-9. | Effects of Two HVUT Options -- 3-axle Single Unit Trucks | VI-17 |
Figure VI-10. | Effects of Two HVUT Options -- 5-axle Tractor-Semitrailer | VI-17 |
Figure VI-11. | Effects of Two WDT Options -- 3-axle Single Unit Trucks | VI-17 |
Figure VI-12. | Effects of Two WDT Options -- 5-axle Tractor-Semitrailer | VI-17 |
Figure VI-13. | 2000 Responsibility for Various Social Costs of Highways | VI-27 |
Figure VI-14. | Highway Cost Responsibility by Vehicle Class | VI-29 |
Figure VI-15. | Comparison of 2000 User Fee and Cost Shares | VI-30 |
HCAS | Highway Cost Allocation Study |
STAA | Surface Transportation Assistance Act |
TS&W | Truck Size and Weight |
DOT | Department of Transportation |
3R | Reconstruction, Resurfacing, and Rehabilitation |
HCA | Highway Cost Allocation |
TRI | Trucking Research Institute |
ESAL | Equivalent Single Axle Load |
VMT | Vehicle Miles Of Travel |
HTF | Highway Trust Fund |
HVUT | Heavy Vehicle Use Tax |
GVW | Gross Vehicle Weight |
FHWA | Federal Highway Administration |
WDT | Weight Distance Tax |
IRS | Internal Revenue Service |
FTD | Federal Tax Deposit |
DRA | Deficit Reduction Act of 1984 |
ATA | American Trucking Associations |
AASHTO | American Association of State Highway and Transportation Officials |
TRB | Transportation Research Board |
NHS | National Highway System |
ISTEA | Intermodal Surface Transportation Efficiency Act of 1991 |
MTA | Mass Transit Account |
CMAQ | Congestion Mitigation and Air Quality |
FMIS | Fiscal Management Information System |
HPMS | Highway Performance Monitoring System |
TIUS | Truck Inventory and Use Survey |
C&P | Conditions and Performance |
NHTSA | National Highway Traffic Safety Administration |
LCCA | Life Cycle Cost Analysis |
M&R | Maintenance and Rehabilitation |
VOC | Vehicle Operating Costs |
PSI | Pavement Serviceability Index |
FTA | Federal Transit Administration |
NEPA | National Environmental Policy Act |
CO | Carbon Monoxide |
CO2 | Carbon Dioxide |
Nox | Nitrogen Oxides |
EPA | Environmental Protection Agency |
PCE | Passenger Car Equivalent |
AADT | Annual Average Daily Traffic |
WsDOT | Washington Department of Transportation |
HUR | Highway User Revenue |
LUST | Leaking Underground Storage Tank |
EPACT | Energy Policy Act of 1992 |
CNG | Compressed Natural Gas |
GVW | Gross Vehicle Weight |
DoD | Department of Defense |
MPG | Miles Per Gallon |
HRFM | Highway Revenue Forecasting Model |
DOE | Department of Energy |
GPM | Gallons Per Mile |
HOV | High Occupancy Vehicle |
SOV | Single Occupancy Vehicle |
NAPCOM | Nationwide Pavement Cost Model |
LTPP | Long Term Pavement Performance |
NBI | National Bridge Inventory |
BNIP | Bridge Needs and Investment Process |
TSM | Transportation Systems Management |
BTS | Bureau of Transportation Statistics |
ITS | Intelligent Transportation System |
FY | Fiscal Year |
AUTO | Automobiles and Motorcycles |
LT4 | Light Trucks with 2-Axles and 4 Tires (Pickup Trucks, Vans, Minivans, etc.) |
SU2 | Single Unit, 2-Axle, 6 Tire Trucks (Includes SU2 Pulling a Utility Trailer) |
SU3 | Single Unit, 3-Axle Trucks (Includes SU3 Pulling a Utility Trailer) |
SU4+ | Single Unit Trucks with 4- or More Axles (Includes SU4+ Pulling a Utility Trailer) |
CS3 | Tractor-Semitrailer Combinations with 3-Axle |
CS4 | Tractor-Semitrailer Combinations with 4-Axle |
CS5T | Tractor-Semitrailer Combinations with 5-Axles, Two Rear Tandem Axles |
CS5S | Tractor-Semitrailer Combinations with 5-Axles, Two Split (>8 feet) Rear Axles |
CS6 | Tractor-Semitrailer Combinations with 6-Axles |
CS7+ | Tractor-Semitrailer Combinations with 7- or more Axles |
CT34 | Truck-Trailers Combinations with 3- or 4-Axles |
CT5 | Truck-Trailers Combinations with 5-Axles |
CT6+ | Truck-Trailers Combinations with 6- or more Axles |
DS5 | Tractor-Double Semitrailer Combinations with 5-Axles |
DS6 | Tractor-Double Semitrailer Combinations with 6-Axles |
DS7 | Tractor-Double Semitrailer Combinations with 7-Axles |
DS8+ | Tractor-Double Semitrailer Combinations with 8- or more Axles |
TRPL | Tractor-Triple Semitrailer or Truck-Double Semitrailer Combinations |
BUS | Buses (all types) |