For sections of the system designed for traffic of less than 1,000 vehicles per day, this picture of an existing road in Texas typifies the character of construction proposed. Consisting of a single 24 foot pavement of appropriate material, with wide shoulders and easy slopes, such sections can probably be constructed at costs ranging between 40 and 60 thousand dollars per mile, depending mainly upon the quantity of grading and the number of grade-separated intersections.
Sections of the system designed for traffic of volumes between 1,000 and 2,000 vehicles per day should be similar in most respects to those serving smaller traffic volumes, but surfaced with pavements of higher type. Cost may range between 50 and 70 thousand dollars with variations in grading quantities and number of grade-separated intersections. The Alabama highway pictured above conforms approximately to the standards proposed.
Plate XI.—Existing highways conforming approximately to standards proposed for light-traffic rural sections of the system.
