Who’s Responsible When a Traffic Detour Causes Confusion and a Collision?
Temporary traffic detours are part of life in a growing city like Tempe. Whether it's due to road construction, utility work, or special events, rerouted traffic is a common headache for local drivers. But when that detour isn’t clearly marked, redirects drivers into dangerous situations, or simply creates chaos, confusion can quickly turn into a crash.
If you were injured in a wreck that was caused—or worsened—by a poorly managed detour, you may have options. The Tempe roadway hazard claim team outlines when a detour becomes a legal liability and how to begin building a case if your accident was preventable.
Why Detours Often Lead to Crashes in Tempe
In a city like Tempe, which balances pedestrian-heavy downtown areas with arterial roads and freeways, detours tend to disrupt more than just traffic patterns. They also interfere with driver expectations. When a detour sign appears suddenly or redirects drivers into unfamiliar intersections, it can cause overcorrection, wrong turns, and sudden lane changes—all of which increase the risk of collisions.
Neighborhoods like Downtown Tempe, North Tempe, and areas near ASU frequently see rerouted traffic due to events, construction, or utility maintenance. These locations are already challenging to navigate, especially for visitors. Poorly executed detours only make matters worse.
Who Is Responsible for Setting Up the Detour?
Depending on the road and the reason for the detour, several different parties might be responsible for its design and implementation:
City of Tempe transportation or public works department
ADOT (Arizona Department of Transportation), if it involves a highway
A private contractor managing a construction site or road repair project
Utility companies performing scheduled maintenance
Event organizers with a permit to reroute traffic during public events
Each of these entities must comply with state and local rules for signage, safety, and visibility. When they fail to do so—and a crash happens as a result—they may be held liable.
What Makes a Detour “Negligent”?
A detour setup may be considered negligent if it fails to provide drivers with adequate notice, clear instructions, or safe passage through the area. This can happen when:
Detour signs are missing, too small, or blocked by foliage or vehicles
Multiple signs contradict each other or point in unclear directions
The detour routes vehicles into oncoming traffic or closed intersections
No lighting or reflective markings are used at night
Temporary traffic control devices are misaligned or absent
In fast-developing neighborhoods like Meyer Park or Escalante, where traffic already weaves through tight residential grids, a poor detour can easily cause a collision between unfamiliar drivers.
Can You Hold the City of Tempe Liable?
Yes—if the city was responsible for designing or approving the detour, and it failed to meet minimum safety standards, it may be considered negligent. But filing a claim against a city in Arizona isn’t as simple as sending a letter.
You must submit a Notice of Claim under Arizona law within 180 days of the incident. The notice must explain:
What happened
Why you believe the city is responsible
The amount you’re seeking in damages
Supporting evidence (photos, reports, etc.)
Failing to file the notice within the 180-day window will usually bar you from suing altogether.
The process is similar to claims involving flooded streets, missing guardrails, or malfunctioning traffic signals.
What If a Private Contractor Caused the Problem?
When a construction crew or third-party contractor is responsible for a detour setup, they may be held liable for any resulting harm. Contractors are legally required to follow Temporary Traffic Control Plans (TTCPs), which outline detour signage, lane closures, and driver instructions.
If a contractor strays from that plan—or creates an unsafe situation through negligence—you may be able to pursue a claim under standard personal injury law without the government’s protections or shortened deadlines.
These claims often arise during major roadway repaving or utility upgrades. Detours near South Tempe, where infrastructure projects are frequent, can be especially chaotic when private companies don’t coordinate with local traffic engineers.
What If Another Driver Caused the Wreck?
It’s also possible that another driver made a mistake while navigating the detour—running a red light, misjudging a turn, or entering a one-way street. Even in that case, liability may not rest solely on the driver. If poor detour signage contributed to their mistake, a portion of fault may still fall on whoever created the detour.
Under Arizona’s comparative fault rules, multiple parties can be held partially responsible. That may include the other driver, the city, a contractor, or even a property owner who allowed signage to be blocked.
What Injuries and Damages Might Be Covered?
Detour-related crashes can cause a wide range of injuries, especially when confusion leads to T-bone impacts, rollovers, or side-swipes at intersections. You may be able to pursue damages for:
Emergency medical treatment
Follow-up care and long-term therapy
Lost wages or earning capacity
Pain and suffering
Car repairs or replacement
Disability-related home or vehicle modifications
Claims involving long-term complications like brain injuries or paralysis may involve more extensive documentation and negotiation.
What to Do After a Detour-Related Crash
If a confusing or poorly marked detour caused your crash, take photos of the scene as soon as possible—particularly the signage (or lack of it), lighting, and road layout. File a police report and request a copy. Document your injuries and vehicle damage in detail. If you suspect the city or a contractor is responsible, act fast: public entity claims expire quickly.
You can learn more about the process in our legal resources section, which covers deadlines, document collection, and where to begin.
