Official Government Website


1983 Borah Peak Earthquake

At 8:06 a.m. (MST) on Friday October 28, 1983 a magnitude 6.9 earthquake (7.3 on the Richter scale) rocked the towns of Challis and Mackay for 30 to 60 seconds. The quake originated along the Lost River Fault below Idaho’s tallest mountain, Borah Peak, at a depth of nearly 10 miles. The fault thrust the Lost River Mountains upward while dropping the Thousand Springs Valley lower. Overall, the mountains and valley shifted apart nearly 14 feet in some places. The quake resulted in the death of two schoolchildren, approximately $12.5 million in property damage, shifts in groundwater location, large visible surface cracks, and rock and landslides. Aftershocks rattled the area for the next few days. One 5.8 magnitude aftershock occurred nearly a year later on August 22, 1984. The largest and most damaging earthquake in Idaho history, President Reagan declared the Borah Peak Earthquake a major disaster on November 18, 1983.

Newspapers record numerous personal accounts and images from that day. After the earthquake, reporters flocked to the Challis and Mackay area. While some residents welcomed the opportunity to tell their stories, others became frustrated by the lack of boundaries and respect for privacy expressed by some reporters. Accounts describe reporters entering people’s private homes without permission to take pictures of the damage. Additional concern arose that the numerous news airplanes and helicopters flying overhead might crash into each other making the situation worse. Luckily, such an incident never occurred.

In the towns of Challis and Mackay, the brick and block masonry of the towns’ buildings crashed to the ground. Two schoolchildren, ages 6 and 7, were buried as a storefront collapsed. People who saw the blocks come down rushed to uncover the children but were unable to save them. They were the only deaths attributed to the quake. Another local woman narrowly escaped her car as bricks crushed it. The bricks struck her in the lower back and legs and nearby co-workers pulled her to safety. She was treated at a local hospital.

ver: 3.5.2 | last updated: