Increased Earth Fissure Activity during Monsoon Storms

The 2018 monsoon season has produced some fresh earth fissure activity in Pinal County. Arizona Geological Survey (AZGS) anticipates that Cochise, La Paz, and Maricopa Counties will experience renewed fissure activity during this monsoon season.

 

An earth fissure is a crack in the earth’s surface. Fissures can cause drainage problems, breach canals, and alter flood patterns or flood control measures. They can also damage underground utilities, infrastructure, roadways, and building foundations.

 

The anticipated fissure activity stems from an AZGS study in Apache Junction, Pinal County. On 9 Aug. 2018, about 2-inches of rain fell on Apache Junction, and an earth fissure in the southwest corner of Apache Junction reopened. It undermined a section of Houston Avenue that had collapsed previously in the summer of 2017.

 

The earth fissure theme at the Natural Hazards in Arizona viewer (http://data.azgs.az.gov/hazard-viewer/) displays the locations and distribution of earth fissures of southern Arizona. The viewer includes strategies for minimizing the impact of fissures on roads, infrastructure and property.

 

What should you do if you find an earth fissure on or near your property?

  • Keep children, pets and livestock away from the fissure.
  • E-mail AZGS (azgs-info@email.arizona.edu); alert your municipal or county emergency manager’s office.
  • Prevent runoff or flood irrigation waters from entering the fissure. Erosion can rapidly increase the fissure width, length and depth.
  • Consult a geotechnician regarding the extent of fissuring and how to minimize damage to your home and property.

 

You can learn more about earth fissures here: https://www.maricopa.gov/4116/Natural .