On Mount Lemmon, volunteers give unemployed rocks a new job: Erosion control

Volunteers in Arizona are repurposing rocks to combat erosion on Mount Lemmon. On a recent Sunday, 10 individuals from Sky Island Alliance, a nonprofit organization dedicated to preserving Arizona's natural environment, worked alongside local experts to install erosion control structures along natural drainages. These structures, composed of rocks arranged in a specific pattern, function like tiny dams, slowing water flow and preventing soil and debris from washing down the mountain into nearby waterways.

The effort is particularly crucial following the Bighorn Fire, which scorched nearly 120,000 acres of the Santa Catalina Mountains in 2020, leaving behind a landscape rife with erosion risks. Since 2023, over 500 such structures have been erected near springs on Mount Lemmon, thanks to the dedication of volunteers and the meticulous mapping efforts of the alliance.

Volunteers, including Ella Marshall, use small red flags placed by experts to guide their rock selection and placement, ensuring the structures are both effective and aesthetically pleasing.