Chapter 2 -- Early Highway Planning
Early highway planning grew out the need for information on the rising tide of automobile and truck usage during the first quarter of the twentieth century. From 1904, when the first automobiles ventured out of the cities, traffic grew at a steady and rapid rate. After the initial period of highway construction which connected many of the nation's cities, emphasis shifted to improving the highway system to carry these increased traffic loads. Early highway planning focused on the collection and analysis of factual information and, on applying that information to the growing highway problems in the period prior to World War II.
In the early years of highway construction, the automobile had been regarded as a pleasure vehicle rather than an important means of transportation. Consequently, highways consisted of comparatively short sections that were built from the cities into the countryside. There were significant gaps in many important intercity routes. During this period, urban roads were considered to be adequate, particularly in comparison to rural roads which were generally not paved.
As the automobile was improved and ownership became more widespread, the idea of a highway network gained in strength. The concept of a continuous national system of highways was recognized in the Federal-Aid Highway Act of 1925 with the adoption of a United States numbered highway system composed of important through routes extending entirely across the nation. This was not a formal highway system but simply a basis for route marking as a guide for motorists (Holmes and Lynch, 1957).
With the adoption of a Federal-aid system, in the Federal-Aid Act of 1921, and the marking of through routes, the focus of highway construction was on "closing the gaps." By the early 1930s, the objective of constructing a system of two-lane roads connecting the centers of population had largely been completed. It was then possible to travel around the country on a smooth, all-weather highway system (U.S. Federal Works Agency, 1949).
With the completion of this "pioneering period" of highway construction, attention shifted to the more complex issues resulting from the rapid growth in traffic and increasing vehicle weights. Figure 1 shows the growth in vehicle registrations, motor fuel consumption, highway expenditures and tax receipts during the period (U.S. Dept. of Commerce, 1954). Early highways were inadequate in width, grade and alignment to serve major traffic loads, and highway pavements had not been designed to carry the numbers and weights of the newer trucks.
It became clear that these growing problems necessitated the collection and analysis of information on highways and their use on a more comprehensive scale than had ever before been attempted (Holmes and Lynch, 1957). A systematic approach to the planning of highways was needed to respond to these problems.
Beginning with the Federal-Aid Highway Act of 1934, the Congress authorized that 1½ percent of the amount apportioned to any state annually for construction could be used for surveys, plans, engineering, and economic analyses for future highway construction projects. The act created the cooperative arrangement between the U.S. Bureau of Public Roads (now the U.S. Federal Highway Administration) and the state highway departments, known as the statewide highway planning surveys. By 1940, all states were participating in this program (Holmes and Lynch, 1957).
As an initial activity, these highway planning surveys included a complete inventory and mapping of the highway system and its physical characteristics. Traffic surveys were undertaken to determine the volume of traffic by vehicle type, weight, and dimensions. Financial studies were made to determine the relationship of highway finances to other financial operations within each state, to assess the ability of the states to finance the construction and operation of the highway system, and to indicate how to allocate highway taxes among the users. Many of the same types of activities are still being performed on a continuing basis by highway agencies (Holmes, 1962).
Electric railway systems were the backbone of urban mass transportation by World War I with over 1,000 street railway companies carrying some 11 billion passengers by 1917 (Mills, 1975). After 1923, ridership on the nation's electric railways began to decline as the motor bus, with its flexibility to change routes and lower capital costs, quickly began replacing the electric the electric streetcar (N.D. Lea Transportation Research Corporation, 1975). With rising costs and the inability to raise fares to cover costs, the financial condition of street railway companies worsened.
In 1930, the heads of 25 electric railway companies formed the Electric Railway Presidents' Conference Committee (PCC). The goal of the PCC was to develop a modern streetcar to match the comfort, performance, and modern image of its competitors, and stem the decline of the street railway industry. The effort took five years and $750,000. It was one of the most thorough and efficiently organized ventures in urban mass transit. The product, known as the "PCC car," far surpassed its predecessors in acceleration, braking, passenger comfort, and noise (Mills, 1975).
The first commercial application of the PCC car was in 1935 in Brooklyn, New York. By 1940 more than 1100 vehicles had been purchased. By 1952, when production was first halted, about 6,000 PCC cars had been produced. The PCC cars did improve the competitive position of streetcars and slow the conversion to buses. But without other improvements, such as exclusive rights of way, it could not stop the long term decline in street railways. By 1960, streetcars remained in only about a dozen cities in the U.S. (Vuchic, 1981).
As the highway system was expanded and upgraded to meet the growth in automobile traffic, the need for high uniform standards for traffic control devices became obvious. These traffic control devices included signs, traffic signals, markings and other devices placed on, over, or adjacent to a street or highway by a public body to guide, warn, or regulate traffic. In 1927, the American Association of State Highway Officials published the Manual and Specifications for the Manufacture, Display and Erection of U.S. Standard Road Markers and Signs. The manual was developed for application of rural highways. Then, in 1929, the National Conference of Street and Highway Safety published a manual for use on urban streets.
But the necessity for unification of the standards applicable to different classes of road and street systems was obvious. To meet that need, a joint committee of the AASHO and the National Conference of Street and Highway Safety combined their efforts and developed the first Manual on Uniform Traffic Control Devices which was published by the BPR in 1935.
Over the years since that first manual, the problems and needs of traffic control changed. New solutions and devices were developed, as well as the standards to guide their application. The original joint committee continued its existence with occasional changes in organization and personnel. In 1972, the Committee formally became the National Advisory Committee on Uniform Traffic Control Devices to the FHWA. The Committee has been responsible for periodic revisions to update and expand the manual in 1942, 1948, 1961, 1971, 1978 and 1988 (U.S. Dept. of Transportation, 1978b; Upchurch, 1989).
As new knowledge became available on the performance of vehicles and highway design features, there was a need to incorporate it into practice. The Committee on Planning and Design Policies of the American Association of State Highway Officials (AASHO) was formed in 1937 for this purpose. The committee's mode of operation was to outline a program of work which was performed by the BPR under the supervision of the Committee Secretary. The BPR gathered known information and developed draft guidance, known a policies, which were revised by the committee. The policies were finally approved by a two-thirds favorable vote of the States.
In the period 1938 to 1944 the Committee under Secretary Joseph Barnett produced seven policies related to highway classification, highway types, sight distance, signing, and intersection design for at-grade, rotaries and grade separations. These policies were reprinted without change and bound as a single volume in 1950 (American Association of State Highway Officials, 1950).
The policies were updated, expanded and rewritten as a single cohesive document and issued as A Policy on Geometric Design of Rural Highways in 1954 (American Association of State Highway Officials, 1954). The policy contained design guidance on the criteria determining highway design, vertical and horizontal alignment, cross section elements, at-grade and grade intersections, and interchanges. The volume, which became known as the "Blue Book," went through seven printings by 1965. It received wide acceptance as the standard guide for highway design. The policy was again reissued in 1966 in revised and updated form to reflect more current information (American Association of State Highway Officials, 1966).
Much of the material in the 1954 Rural Policy applied both to urban and rural highways. As new data and research results became available on urban highways, the AASHO Committee decided to issued a separate policy for the geometric design of urban highways (American Association of State Highway Officials, 1957).
The development of these policies typified the approach to highways standards. Research engineers collected data on the performance of vehicles and highways. These data were brought together in the form of design standards, generally by staff of the BPR under the guidance of the AASHO. Eventually, they became part of highway design practice through agreement of the States. As a result of their factual basis and adoption through common agreement, the policies had immense influence on the design of highways in the United States and abroad.
By the mid 1930s, there was considerable sentiment for a few long-distance, controlled-access highways connecting major cities. Advocates of such a highway system assumed that the public would be willing to finance much of its cost by tolls. The U.S. Bureau of Public Roads was requested by President Roosevelt in 1937 to study the idea, and two years later it published the report, Toll Roads and Free Roads (U.S. Congress, 1939).
The study recommended the construction of a highway system to be comprised of direct, interregional highways with all necessary connections through and around cities. It concluded that this nationwide highway system could not be financed solely through tolls, even though certain sections could. It also recommended the creation of a Federal Land Authority empowered to acquire, hold, sell, and lease land. The report emphasized the problem of transportation within major cities and used the city of Baltimore as an example (Holmes, 1973).
During the 1920's and early 1930's, a number of studies were conducted to determine the capacity of highways to carry traffic. Early efforts were theoretical but, gradually, fields studies using observers, cameras and aerial surveys created a body of empirical data on which to base capacity estimates. By 1934, it was clear that a coordinated effort was needed to integrate the results of the various studies and to collect and analyze additional data. The BPR launched such an effort from 1934 to 1937 to collect a large quantity of data on a wide variety of roads under different conditions (Cron, 1975a).
In 1944, the Highway Research Board organized a Committee on Highway Capacity to coordinate the work in this field. Its chairman, O.K. Normann, was the foremost researcher on highway capacity at that time. By 1949, the Committee had succeeded in reducing the enormous volume of factual information on highway capacity to a form that would be usable to highway designers and traffic engineers. The results were first published in Public Roads magazine, and then as a separate volume entitled, the Highway Capacity Manual (U.S. Dept. of Commerce, 1950). The manual defined capacity, and presented methods for calculating it for various types of highways and elements under different conditions. This manual quickly became the standard for highway design and planning. More than 26,000 copies of the manual were sold, and it was translated into nine other languages.
The Committee on Highway Capacity was reactivated in 1953, again with O.K. Normann as chairman, to continue the study of highway capacity and prepare a new edition of the manual. Much of the work was done by the staff of the BPR. The new manual, which was issued in 1965, placed new emphasis on freeways, ramps, and weaving sections because they had come into widespread use. A chapter on bus transit was also added. Other types of highways and streets continued to receive complete coverage. This manual, like its predecessor, was primarily a practical guide. It described methods to estimate capacity, service volume, or level of service for a specific highway design under specific conditions. Alternately, the design to carry a given traffic demand could be determined (Highway Research Board, 1965).
The third edition the Highway Capacity Manual was published by the Transportation Research Board in 1985. It reflected over two decades of empirical research by a number of research agencies primarily under the sponsorship of the National Cooperative Highway Research Program and the FHWA. The procedures and methodologies were divided into three sections on freeways, rural highways, and urban streets with detailed procedures and work sheets. The material in the third edition offered significantly revised procedures in many of the areas, and included entirely new sections on pedestrians and bicycles (Transportation Research Board, 1985c and 1994).
In April 1941, President Roosevelt appointed the National Interregional Highway Committee to investigate the need for a limited system of national highways to improve the facilities available for interregional transportation. The staff work was done by the U.S. Public Roads Administration, which was the name of the Bureau of Public Roads at that time, and in 1944 the findings were published in the report, Interregional Highways (U.S. Congress, 1944). A system of highways, designated as the "National System of Interstate and Defense Highways," was recommended and authorized in the Federal-Aid Highway Act of 1944. However, it was not until the Federal-Aid Highway Act of 1956 that any significant work on the system began.
This study was unique in the annals of transportation planning and the implementation of its findings has had profound effects on American lifestyles and industry. The study brought planners, engineers, and economists together with the highway officials responsible for implementing highway programs. The final route choices were influenced as much by strategic necessity and such factors as population density, concentrations of manufacturing activity, and agricultural production as by existing and future traffic (Holmes, 1973).
The importance of the system within cities was recognized, but it was not intended that these highways serve urban commuter travel demands in the major cities. As stated in the report, "...it is important, both locally and nationally, to recognize the recommended system...as that system and those routes which best and most directly join region to region and major city to major city" (U.S. Congress, 1944).
The report recognized the need to coordinate with other modes of transportation and for cooperation at all levels of government. It reiterated the need for a Federal Land Authority with the power of excess condemnation and similar authorities at the state level.
This site will be under constant change. If you have any suggestions for improving the site, please send a message to Lynette Engelke.
This page was updated May 18, 1998.