A lot of what we write about is infrastructure: thermal cameras, lowered signs, red reflectors, detection systems. Those matter, and Arizona has invested in them.
But there is a countermeasure that costs less than any of them, works on every road in the state, and stops the problem before a vehicle ever reaches a ramp. It is the decision not to drive impaired.
Why impairment is the center of the problem
ADOT's wrong-way driving page states that two out of three wrong-way crashes are caused by impaired drivers, and notes that those drivers often have blood-alcohol levels more than twice the legal limit.
The AAA Foundation for Traffic Safety's national study of fatal wrong-way crashes on divided highways from 2014 through 2023 also identified alcohol-impaired drivers as a group at elevated risk.
Impairment affects exactly the skills needed to avoid a wrong-way entry: reading signs, judging direction, processing what you see, and noticing that something is wrong. A sober driver who turns onto the wrong ramp is likely to see the red sign and stop. An impaired driver may not.
Every other layer is downstream
Roadside technology mostly works after the mistake has been made. A detection system finds a vehicle already going the wrong way. A flashing sign tries to get the driver's attention after they have entered. Troopers respond to a vehicle that is already a danger.
Those layers save lives. They also depend on an impaired driver noticing a warning, or on the response arriving in time.
A sober ride home does not depend on any of that. The impaired driver is never behind the wheel, so there is nothing to detect, warn, or intercept.
Options that work
Rideshare and taxis. In much of the Phoenix area, a ride is available within minutes. The cost of a ride is small compared with the costs of a crash or an arrest.
A designated driver. Someone in the group who commits to staying sober for the whole evening, not one who plans to have "only one or two."
Staying where you are. A friend's couch, a hotel room near the event, or simply waiting until you are sober.
Transit, where it runs at the hour you need it.
A call to family or a friend. Many families have a standing agreement that anyone can call for a ride at any time, no questions asked that night.
Make the plan before the first drink
The problem with deciding later is that alcohol affects judgment, including judgment about whether you are okay to drive. The person making the call at midnight is not the same person who could have made it at 7 p.m.
That is why the plan has to come first:
- Decide how you are getting home before you leave the house.
- Set up the rideshare app ahead of time, with payment ready, so it is quick to use later.
- Tell someone your plan so they can hold you to it.
- If you drove there, decide in advance that the car stays parked if you drink, and know how you will get it back the next day.
Helping someone else
Sometimes the person who needs a ride is not you.
If a friend is about to drive after drinking, the most effective thing you can do is step in. Offer to drive them, call them a ride, or ask them to stay. Taking someone's keys is uncomfortable, and it can feel like overstepping. It is also one of the few interventions that stops a wrong-way crash before it starts.
Hosts can help too: serve food, offer non-alcoholic drinks, stop serving well before the event ends, and keep an eye on who is planning to drive.
Late nights and weekends
ADOT notes that three out of four wrong-way crashes happen between 6 p.m. and 6 a.m., one-third between midnight and 3 a.m., and more than half on weekends. Those are the hours when a plan for a sober ride does the most good, both for the people taking the ride and for everyone else on the road.
A small decision with a large effect
We will keep writing about technology and engineering, because those layers protect drivers who never read anything we publish. But for anyone reading this, the most useful step available tonight is simple: if you are drinking, do not drive, and do not let your friends drive.
NMWWD is a Phoenix-based nonprofit working to prevent wrong-way crashes. If you would like to help us spread this message across Arizona, get involved or support the work.
Sources: Arizona Department of Transportation — Wrong-Way Drivers · AAA Foundation for Traffic Safety, Fatal Wrong-Way Crashes on Divided Highways, United States, 2014–2023