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U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

The Dwight D. Eisenhower System of Interstate and Defense Highways

In 1998, with the Interstate System essentially complete, FHWA's Office of Engineering compiled information about development of the program. In making this information available to the public, we have not updated the material. All information is as of 1998 when the Office of Engineering compiled the report.

Engineering Data

Report Index


Part I - History

Part II -- Mileage

Part III -- Cost

Part IV -- Funding

Part V -- Interstate Withdrawal-Substitution Program

Part VI -- Interstate Status and Progress

Part VII -- Miscellaneous Interstate Facts

Part VIII -- Other Interstate Programs


What This Notebook Attempts to Do

Part I - History
Many authors have written detailed histories of the Federal-Aid Highway Program and in particular the Interstate System. The high points in the development of the Interstate System are summarized in Part I of this notebook. Part I also includes a bibliography of historical books and articles on the origins of the Interstate System.

Part II - Mileage
Interstate routes have been designated or added to the system under several provisions of law. Part II includes various types of listings of all the Interstate routes, and their lengths and indicates the mileage designated under each provision.

Part III - Cost
The Interstate Cost Estimate (ICE) process is described and the costs of the System with breakdowns by State and route are provided from the 1991 ICE and updated to 1998.

Part IV - Funding
Details on annual authorizations, ICE reports to Congress, apportionments, allocations, transfers, etc.

Part V - Withdrawal-Substitution
Many segments became controversial for a number of reasons and were never built as originally planned. Part V identifies these routes and describes the two parts of the Interstate Withdrawal-Substitution Program, Howard-Cramer substitutions under 23 U.S.C. 103(e)(2) and withdrawals under 103(e)(4). Maps are included showing all withdrawals.

Part VI - Status/Progress
Includes summaries of year-by-year and State-by-State progress on constructing the system and its current status.

Part VII - Miscellaneous Facts
Provides a number of facts such as numbering of routes and exits, traffic, tunnels, and includes trivia questions frequently posed to FHWA about the first, the longest, the most, the least, etc.

Part VIII - Other Programs
Describes some of the other Interstate programs including 3R, 4R, 4R Discretionary, Maintenance, and Reimbursement.


Much of the credit for developing the Interstate System is given to President Eisenhower, members of Congress, and FHWA and State Leaders.

This notebook is dedicated to the four engineers who led the BPR - FHWA Washington Office branch which for nearly 40 years daily dealt with the Interstate System, its cost and funding, eligibility issues, legislation, completion status, etc. The branch was variously known as the Interstate Reports Branch, the Interstate Management Branch, and the Interstate & Program Support Branch. We are indebted to these four engineers:

Henry R. Paterick
Curtis L. Shufflebarger
Lawrence A. Staron
Donald J. Marttila