Permanently signed detour route
[a] The state of New South Wales in Australia has signposted 'D' and 'D1' detour routes on the M1 Pacific Motorway between Newcastle and Sydney and the 'D5' for the M5 East in the case of temporary road closures.
History Halton was the first jurisdiction in Ontario to create EDRs, although it initially referred to them as Emergency Diversion Routes.
These signs were first deployed along a limited stretch of the Queen Elizabeth Way in March 2001,[3] between Dorval Drive and Trafalgar Road in Oakville and between Bronte Road and Burloak Drive in Burlington, both the location of major ravines with limited alternative crossings.
[2][4] Following Halton's tests, the MTO and the Ontario Good Roads Association formed a joint task force, and using the RCAP as a model, developed the Emergency Detour Route program.
As the detours use secondary roadways, federal administrative rules require consultation with local authorities when planning the detour routes, and routes are selected to minimize distance, stops (i.e. traffic signals), and disruption to nearby communities as much as possible.
According to the Swedish Transport Administration's guidelines a permanent detour route should be able to handle all the traffic when it comes to capacity, weight, height, etc.
[15] Symbols come in a shapes, with a solid and hollow version, including circle, triangle, square and diamond.
[16] The federal Manual on Uniform Traffic Control Devices introduced signage for these routes in its eleventh edition in December 2023.
Emergency routes have been gradually put in place as part of a broader plan by the Michigan Department of Transportation (MDOT) to upgrade its ITS network across the state.
These detours may or may not follow MDOT-maintained State Highways, however, and some portions of the routes pass through urban or suburban areas.
According to MDOT, "this route would only be used in emergency situations and worst-case scenarios impacting the entire bridge structure.
[25][26] Ohio has established a permanent detour scenario of Interstate 70 east of Columbus, due to frequent flooding.
