is no doubt also, as indicated by the diagram, that acquircd rights-of-way are inadequate. As further indicated, there is generally a reasonable accord between traffic volume and the number of pavement lanes provided and also between the amount and character of the traffic and the class of pavement or surface in place. A slightly inadequate width of the pavement lanes appears on a considerable mileage, usually near cities.
The unsatisfactory conditions found on the main roads of the country and indicated typically in plate 56, are the natural consequences of circumstances surrounding their construction, The roads as they exist at present, are the product of construction operations carried on over a period of more than 20 years. It is estimated that at least 11,000 miles of road surface on the State primary systems, constructed prior to 1921, is still in service, widened perhaps, but still on its original alinement and still unchanged in basic design. This mileage represents 14 percent of the surfaced mileage in existence prior to 1921. A large part of the existing improved mileage was built during the twenties and still conforms to the standards then considered adequate.
One of the handicaps under which roadbuilders have labored during the period of development of the motor vehicle is that they must expect the roads they build to outlast the vehicles that exist at the time of their building. There is a substantial mileage of road pavement still in use that was built 25 years ago or longer, serving today kinds of vehicles that were undreamed of when they were built. Small wonder if such pavements, designed to be used by vehicles capable of a top speed of 30 miles an hour, are found somewhat inadequate for the service of vehicles that may be, and are frequently driven at speeds above 60 miles an hour.
When the oldest of still existing pavements were built there were only 2 or 3 million primitive motor vehicles, but there was already a strong demand for improved roads, and especially for roads connecting the larger cities, in which the great majority of the vehicles were owned. The recognized superior need for such roads resulted in their inclusion in State highway systems and, in 1921, the Federal-aid highway system, and the enactment of laws limiting expenditure of State and Federal funds largely to the improvement of these systems.
In the beginning nearly all of the mileage included in these systems had no improvement worthy of the name. The need of improvement in some degree was coextensive with the system; and the primary need was for the laying of surfaces which—to use the popular phrase—would “get the traffic out of the mud.”
In general, the improvement began near each city and larger town and proceeded outward from these to eventual junction of the extending arms. While unimproved gaps remained there was constant pressure to close them as rapidly as possible in order to “get the traffic through.” The full value of the improved sections was unrealized so long as at one or both ends they delivered their traffic to a road still unimproved. Residents along the unimproved sections naturally wanted to see their sections improved also, but they were scarcely more vigorous in pressing their claims than were those already served with pieces of improved highways that failed to take them where they wanted to go.
