Arizona monsoon hazards: Flooded areas risk engine damage and tree falls

Published September 27, 2026 5:17 PM MST

While it might be the end of the monsoon season, the weather is still expected to be active, with rain possibly on the way early this week. With it, comes a danger seen every time a storm moves through.

Active Weather:

Flooded roads can look passable, but for drivers who take the chance, the consequences can be costly.

Underpasses can turn into flood zones in a matter of minutes when a storm moves in. While everyone has somewhere to be, safety officials and mechanics emphasize that one thing isn’t worth the risk — trying to drive through floodwater.

Potential Damage:

Auto repair expert Luis Medina, with After Hours Auto and Truck, warns driving through floodwater can cause serious damage, from electrical problems to brake failure. Worst case, water can get into the engine, hydro-lock it, and leave drivers facing an $8,000 to $10,000 replacement.

"If water were to get up here and splash over what this does, it sucks," Medina said, referring to water splashing over the hood of a vehicle. "So all the water would go in here, season into where the intake manifold is. Go inside the engine and hydrologic it."

It does not take much water to create a serious problem. Public safety officials say just 12 inches of moving water can sweep a car off the road. 

"If your car does start to hydroplane, please ease off the gas pedal and do not hit the brakes. If your car starts to get flooded, if you can safely get out of your car and get to higher ground, that's what we recommend," Phoenix Fire Captain Todd Keller said. 

Tree Removal Surge:

During monsoon season, tree removal services operate more reactively, responding to calls as they come in. During the rest of the year, people tend to schedule their services in advance. 

Local perspective:

B and C Tree Service usually gets 40 to 50 calls a day during monsoon season compared to the usual five to 10 calls during non-monsoon months.

Problems usually occur in areas where there has not been proper irrigation, where there is too much water too soon, causing roots to spread out rather than grow deep. More issues are also seen in areas with younger trees, particularly in developing communities like Peoria and Surprise. To prevent trees from falling, property owners should know what to look out for before a storm comes in.

"If you see some cracking happening in the soil, usually that means that the root structure's been compromised; that there's some movement within the root structure so look for any kind of cracking in the dirt," said Alex Carey, owner of B and C Tree Service.

For any younger trees, Carey recommends placing stakes on them for a year or two to hold them up during monsoon season.

What you can do:

Officials remind drivers to avoid flooded streets, underpasses, and low-water crossings, and never try to drive through moving water. Drivers should check their brakes and tire tread replace worn windshield wipers, and keep a safety and emergency kit in the car. 

 If flooding is reported, drivers should give themselves extra time and take an alternate route.

The Source: Information in this report was gathered from Alex Carey, owner of B and C Tree Service; Luis Medina, auto repair expert with After Hours Auto and Truck; and public safety officials.

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