Editing Traffic (section)

==Congestion mitigation==
{{main|Traffic congestion}}

===Rush hour policies===
Some cities adopt policies to reduce rush-hour traffic and pollution and encourage the use of [[public transportation]]. For example, in [[São Paulo]], [[Manila]]<ref>Andrew Downie (21 April 2008). "The World's Worst Traffic Jams". Time. Retrieved 2008-06-20</ref> and in [[Mexico City]], each vehicle has a specific day of the week in which it is forbidden from traveling the roads during rush hour. The day for each vehicle is taken from the [[license plate]] number, and this rule is enforced by traffic police and also by hundreds of strategically positioned traffic cameras backed by computerized image-recognition systems that issue tickets to offending drivers.

In the United States and Canada, several expressways have a special lane (called an "HOV Lane" – [[High Occupancy Vehicle Lane]]) that can only be used by cars carrying two (some locations-three) or more people. Also, many major cities have instituted strict parking prohibitions during rush hour on major arterial streets leading to and from the central business district. During designated weekday hours, vehicles parked on these primary routes are subject to prompt ticketing and towing at owner expense. The purpose of these restrictions is to make available an additional traffic lane in order to maximize available traffic capacity. Additionally, several cities offer a public telephone service where citizens can arrange rides with others depending on where they live and work. The purpose of these policies is to reduce the number of vehicles on the roads and thus reduce rush-hour traffic intensity.

Metered freeways are also a solution for controlling rush hour traffic. In Phoenix, Arizona and Seattle, Washington, among other places, metered on-ramps have been implemented. During rush hour, traffic signals are used with green lights to allow one car per blink of the light to proceed on to the freeway.

Rush hour is typically caused by multiple cars all going to once place at the same time. There is no way to fix the issue because the economy has set times for work, school, and running errands all during the same hours. There is no avoiding this problem because it exists in every major metropolitan area in the world. <ref>{{Cite web |last=Downs |first=Anthony |date=2004-01-01 |title=Traffic: Why It's Getting Worse, What Government Can Do |url=https://www.brookings.edu/research/traffic-why-its-getting-worse-what-government-can-do/ |access-date=2023-06-02 |website=Brookings |language=en-US}}</ref>

===Pre-emption===
In some areas, [[emergency service|emergency responders]] are provided with specialized equipment, such as a [[Mobile Infrared Transmitter]], which allows emergency response vehicles, particularly [[Fire apparatus|fire-fighting apparatus]], to have high-priority travel by having the lights along their route change to green. The technology behind these methods has evolved, from panels at the fire department (which could trigger and control green lights for certain major corridors) to optical systems (which the individual fire apparatus can be equipped with to communicate directly with receivers on the signal head). In certain jurisdictions, public transport buses and government-operated [[winter service vehicle]]s are permitted to use this equipment to extend the length of a green light.<ref>{{citation |mode=cs1 |section=625 ILCS 5/12-601.1. Traffic control signal preemption devices. |title=Illinois Compiled Statutes |url=http://www.ilga.gov/legislation/ilcs/documents/062500050k12-601.1.htm |publisher=Illinois General Assembly |access-date=2 December 2018 |date=2 July 2003}}</ref>

During emergencies where evacuation of a heavily populated area is required, local authorities may institute [[contraflow lane reversal]], in which all lanes of a road lead away from a danger zone regardless of their original flow. Aside from emergencies, contraflow may also be used to ease traffic congestion during rush hour or at the end of a sports event (where a large number of cars are leaving the venue at the same time). For example, the six lanes of the [[Lincoln Tunnel]] can be changed from three inbound and three outbound to a two/four configuration depending on traffic volume. The Brazilian highways [[Rodovia dos Imigrantes]] and [[Rodovia Anchieta]] connect [[São Paulo]] to the [[Atlantic]] coast. Almost all lanes of both highways are usually reversed during weekends to allow for heavy seaside traffic. The reversibility of the highways requires many additional highway ramps and complicated [[interchange (road)|interchanges]].

===Intelligent transportation systems===
An [[intelligent transportation system]] (ITS) is a system of hardware, software, and operators-in-the-loop that allow better monitoring and control of traffic in order to optimize traffic flow. As the number of vehicle lane miles traveled per year continues to increase dramatically, and as the number of vehicle lane miles constructed per year has not been keeping pace, this has led to ever-increasing [[traffic congestion]]. As a cost-effective solution toward optimizing traffic, ITS presents a number of technologies to reduce congestion by monitoring traffic flows through the use of sensors and live cameras or analysing cellular phone data travelling in cars ([[floating car data]]) and in turn rerouting traffic as needed through the use of variable message boards (VMS), highway advisory radio, on board or off board navigation devices and other systems through [[integration of traffic data with navigation systems]]. Additionally, the roadway network has been increasingly fitted with additional communications and control infrastructure to allow traffic operations personnel to monitor weather conditions, for dispatching maintenance crews to perform snow or ice removal, as well as intelligent systems such as automated bridge de-icing systems which help to prevent accidents.