Traffic engineering is a field of study that encompasses a number of civil engineering disciplines. It concerns itself with designing transportation systems, aiming to create safer, more efficient, and more cost-effective systems for the world. Traffic engineering traditionally handles things like bridges, roads, and railways, as well as traffic lights, signs, and other signals. Modern traffic engineering also makes use of more advanced technologies, such as traffic sensors, dynamic signage, and central computers to handle traffic patterns in an effort to relieve congestion.
The history of traffic engineering can be traced back thousands of years, to the great roads of the old empires, such as Rome. Early roads were built to last under the steady advancement of humans and horses, and were generally designed to last for hundreds of years. Traffic flows were not a problem until much later, when densely populated urban centers experienced bottlenecks and dangerous traffic patterns, even in the age of horse-drawn carriages. Large streets were adopted to try to limit this problem, and in response to the use of narrow streets as barricades during many of the great revolutions of the 19th century.
In the early- and mid-20th century, with the advent of the automobile, traffic engineering became an even more important discipline. In the United States, traffic engineering saw an enormous boom during the 1950s. In 1956 the Federal-Aid Highway Act was passed, setting the groundwork for a national Interstate Highway system, based loosely on the German Autobahn. Early traffic engineering in the United States was therefore focused largely on strategic decisions, as an Interstate system was seen as necessary to have a more secure homeland.
As traffic increased in the United States and abroad, particularly in urban areas, new areas of study in traffic engineering opened up. Finite space within cities for roads made them particularly susceptible to bottlenecking, as they couldn’t simply be continuously widened, as became the norm for the Interstate system in more rural and suburban areas. Managing traffic flows became a huge project, as engineers tried to simulate and model traffic to best predict where lights should be placed, how they should be timed, and how roads could be shifted to increase transport efficiency.
Modern communications and sensor equipment provided a huge boon to traffic engineering, by giving it more informational tools to simulate traffic flows in real time. One particularly advanced system that was introduced early was the NAVIGATOR, or Advanced Transportation Management System. It was constructed in Atlanta in the lead up to the 1996 Olympic Games, in an effort to minimize the negative impact of an additional two-million visitors to Atlanta’s already bursting-at-the-seams traffic grid.
The NAVIGATOR system uses more than 450 closed-circuit television cameras to watch traffic, and massive batteries of radar and video detectors to quickly identify accidents or snarls so help can be deployed. The system was also one of the largest early deployments of traffic metering on on-ramps, letting cars on in a gradual trickle to alleviate congestion and stopped traffic on the Interstate itself. More than fifty changeable signs, and information kiosks spread throughout the city complete the system, allowing central controllers the ability to dynamically shift the grid and immediately alert motorists to the changes.
