There are many reasons why motorists might be forced to detour from their chosen travel route: motor vehicle collision, road construction, flooding, fire, hazardous materials incident, or any number of other situations. For a long-term detour, appropriate signage is used to demarcate the new route, relieving the driver of having to know the area well. The problem comes with the short-term detour, where little or no signage will be used. This detour is usually set up by a police officer, at a point where vehicles can get around an incident.
The question is how can you detour without getting lost in an area that you are unfamiliar with? If traffic is light, you may be able to ask the police officer that is redirecting you. If this option is not feasible, then you have to get creative. A GPS would be my first thought, keeping in mind that it may want you to turn around and go through the incident path; keep driving forward, it will recalculate. Most phones have mapping systems that can be used. If these are unavailable, then you may want to call someone, and get them to look it up for you. The option that is most frequently used is that you keep driving around until you find your way around the incident and get back on your main travel route.
Neighborhoods seem to be the worst place to be detoured through. There have been times when vehicles have been detoured through our neighborhood. I live on a dead end street, and when cars come this way, they are not expecting it. You must keep in mind that the speed limit through most subdivisions is 25 MPH, unless otherwise designated. It is important to slow down in these neighborhoods, due to people being out and about while you are lost, attempting to read street signs and get out of there.
One thing that might help, when there are no other options, is to use your directional indicator to your advantage. If you were traveling south before your detour, then getting back to a point where you can travel south again, will hopefully get you where you need to go on another route, or may be help to get you back on your preferred route. One thing to always keep in mind is this, if you are on Interstate 95, Route 1 parallels it from Maine to Florida.
The best way to get around a problem area is to avoid it at all costs, if possible. Traffic reports and alert signage should help you know where to exit. Some incidents require that an entire roadway needs to be shut down for a long period of time. If you are caught in this, you will be at the mercy of law enforcement officials. If you have medical issues, then you need to plan ahead. For some people, running out of oxygen is not an option, but could happen in some backups. My wife and I got caught in Nags Head traffic, evacuating due to an approaching hurricane. Traffic on 158 was at a standstill. It took us about 8-10 hours to get home that day, in heavy rain and wind. This was a case of waiting until the last minute to leave. Though this happened many years ago, it is a good example of what can happen.