Needed improvements on deficient mileage of the Federal-aid primary system average $140,000 per mile on rural sections and $800,000 per mile on urban sections. On the Federal-aid secondary system the average cost is about $40,000 per mile. There are, of course, considerable variations in these average costs among and within the various States.
The kind of work also varies widely. From a fourth to a third of the mileage in need of improvement on the various systems requires only relatively minor work such as resurfacing or widening. Costs of such work are from a third to a half of the previously cited averages for all work.
At the other extreme are those needed improvements involving construction of a complete new road to replace an old one. The amount of such needed work varies on each system. For example, only one-tenth of the deficient mileage on the secondary system involves the construction of a complete new road on new location, whereas over a third of the needed improvements on the urban portions of the primary system is in this category. Costs of such new construction are about double the previously cited averages for all work. Between these extremes falls the remaining mileage of needed improvements, generally involving substantial reconstruction work along existing alinements.
The estimated work needed on the Federal-aid primary system (excluding the interstate system) during the 10-year period 1955–64 totals $29.9 billion, of which $19.9 billion is in rural and $10 billion in urban areas.
The estimate of needs on the Federal-aid secondary system in the 10-year period totals $15 billion, of which $10.1 billion is for roads under State control and $4.9 billion for roads under local control.
Other State highways
There are now in service 86,000 miles of non-Federal-aid roads and streets under the jurisdiction of State highway agencies—76,000 miles are rural and 10,000 miles are urban. The States anticipate substantial additions to this mileage. By the end of the 10-year period, it 1964, they estimate that 114,000 miles will be in service, 102,000 rural and 12,000 urban.
It was estimated that 59 percent of the existing rural mileage and 47 percent of the existing urban mileage will require improvement within the 10-year period. The cost of needed improvements averages $51,000 per mile for rural mileage and $260,000 per mile for urban mileage. There are wide variations in these averages, however, between and within States and by type of work. The total needed work on this mileage during the hag period 1955–64, according to State estimates, amounts to $5.5 billion, of which $3.7 billion is in rural and $1.8 billion in urban areas.
Other rural roads and city streets
Over three-fourths of the national total road and street mileage is in the category of local service roads and streets. With a few relatively minor exceptions, this mileage is under the administrative jurisdiction of local units of government (below the State level). In existence at present are nearly 2,300,000 miles of rural roads and about 320,000 miles of urban streets. In 1964, at the end of the 10-year
