By Rob Hallberg

I grew up in the DC area and it often surprises my friends when I reveal that Tucson has flooding problems. Floods in the Desert? They just don’t understand.

“Desert” refers to a climate with minimal rainfall so how can we have floods? One problem is caliche, which is a naturally forming soil layer found in much of Tucson. Caliche combines calcium, primarily from rainwater, with carbon dioxide to form calcium carbonate. Calcium carbonate forms a water barrier which causes poor drainage.

Our lack of precipitation adds to the problem as rainwater “bounces” off the hardened soil and runs to find the lowest level. It can actually create extremely dangerous situations as large amounts of water will move very rapidly over hardened soil. So how do we get around during the monsoon season?

First and foremost, never drive into an area where the highway is covered with water, especially if the storm is still active. Floodwaters can cross an area without warning and may actually take your car with them. As flooding occurs throughout the Tucson area, it would be best to stay at home until the danger is over.

Pay particular attention to Flood Warning signs as these are areas that are particularly hazardous. Arizona even has a law, commonly known as the “Stupid Motorist Law”, where people who drive through a street covered in water and get stuck have to foot the bill for rescue efforts.

If your home is located in a flood zone, then there are other steps you should take but that is out of the scope of this article. For driving, however, understand that there are real dangers with flooding so stay alert and make good, safe decisions! And we will, hopefully, have lots of rain this monsoon season.

About author View all posts

Guest Author