The Federal Highway Act, approved November 9, 1921 provided as follows:
Sec. 3. All powers and duties of the Council of National Defense under the act entitled “An act making appropriations for the support of the Army for the fiscal year ending June 30, 1917, and for other purposes,” approved August 29, 1916, in relation to highway or highway transport, are hereby transferred to the Secretary of Agriculture, and the Council of National Defense is directed to turn over to the Secretary of Agriculture the equipment, material, supplies, papers, maps, and documents utilized in the exercise of such powers. The powers and duties of agencies dealing with highways in the national parks or in military or naval reservations under the control of the United States Army or Navy, or with highways used principally for military or naval purposes, shall not be taken over by the Secretary of Agriculture, but such highways shall remain under the control and jurisdiction of such agencies.
The Secretary of Agriculture placed the responsibility for the detailed action required by this legislation upon the then Bureau of Public Roads, and the Bureau at once sought the advice of the War Department on the location and character of highways necessary to meet the military requirements of the national defense; first, with respect to those sections of highway which for military reasons it was desirable to include in the Federal-aid system, and second, with respect to the standards of road and bridge design which military necessity might require.
The War Department's findings on the first point took the form of the so-called “Pershing map” of 1922. This map indicated, for the first time, a system of national routes deemed by the responsible military authorities to be of special importance from the standpoint of national defense.
Upon the second point, the War Department stated that military requirements would impose no standards for roads or bridges superior to those required to accommodate all classes of commercial traffic.
In the designation and improvement of the Federal-aid highway system, the Public Roads Administration and the State highway departments have been guided by this advice, which was promptly given and which has since been consistently supplemented by the military authorities. The routes indicated to be of military importance have been included in the system designated for improvement with joint Federal and State funds. Policies regarding types and degrees of improvement have been shaped on the assumption that the forms of construction meeting normal peacetime requirements would generally suffice for any probable military or defense use. These policies, adopted within the findings and conclusions of the military authorities and carried into effect over a long period by the State and Federal highway improvement programs, impose certain reciprocal obligations upon those responsible for the design of all types of heavy equipment and ordnance proposed for movement over the highways and particularly over the bridges.
When the first World War began in 1914, the motor vehicles in use in the United States numbered only 1,711,000; by 1925 this number had grown to the startling total of 19,937,000 units, and in 1940 to the highest record of 31,800,000 registered units. The Federal-aid, and the major exclusively State-highway programs have developed simultaneously with this rapid growth in the numbers and use of the motor vehicle.
In building roads to serve the expanding needs of the resulting traffic, the extensive mileage requiring improvement and the relatively limited funds available have at all times prevented the adoption of
