Controlled rock blasting is the process of cracking rock material by using a small and controlled amount of explosives. This allows for a quick and inexpensive way to remove rock. Site excavation for the Uptown Parking Garage Project will use a combination of mechanical methods (heavy excavation equipment) and controlled rock blasting techniques to remove rock materials encountered on each site. The contractor will employ mechanical methods using heavy equipment (bulldozers and excavators with hydraulic rock hammers) to remove the weaker and less dense rock strata, and explosive (controlled rock blasting) techniques to remove the harder and more dense rock strata.

The city and their excavation contractor, Fann Contracting, decided to incorporate controlled rock blasting into this project based on the dense rock conditions and more cost effective method.

Controlled rock blasting operations began at the site of the Uptown Parking Garage in late-August 2024 and will continue twice a week until winter 2024/2025.

Grand Canyon Shooters will be performing the controlled rock blasting operations for the Uptown Parking Garage Project, with monitoring performed by Arizona Monitoring Services.

Arizona Monitoring Services are serving as vibration consultants. In summer 2024, Arizona Monitoring Services conducted pre-blast condition surveys to residents within 500 feet of planned blasting sites to document the existing conditions of each resident’s home. When working closely to structures, seismic and air blast conditions are closely monitored. A blasting seismograph is set up prior to a blast and begins recording at threshold levels of vibrations, which is referred to as the trigger level. This level is set low enough to detect the blast vibrations, but high enough that it will not accidentally record non-blast vibrations (such as nearby human activity). Once triggered, the data is recorded, stored in the seismograph and evaluated to ensure the vibrations are within appropriate limits.

Responses to controlled rock blasting are subjective. During a controlled rock blast vibration event, people inside a building may experience the vibrations differently than those outside of a building. Those inside of a building may see the windows rattle along with other structure responses. Someone outside of a building may hear the controlled rock blast, but will likely notice nothing else. All controlled rock blasting operations are planned to be in compliance and fall below the regulated limits that are in place to protect nearby structures. It is normal and expected to feel and hear the blast if you live in close proximity to the site. Please watch the video below to get an idea for what to expect when blasting occurs.

If you live within 500 feet of a planned controlled rock blasting area, you should have completed a pre-blast survey with Arizona Monitoring Services. If you do not live in this area, no action is required.

The controlled rock blasting operations for the Uptown Parking Garage will not “blow up” the hillside. The controlled rock blasting operations being performed are small, controlled blasts to remove areas with dense rock. Please watch the video below to get an idea for what to expect when blasting occurs.

Controlled rock blasting will cause dust within the blasting site, but water spraying dust mitigation techniques will be deployed and air quality is being monitored. Residents within 500 feet of blasting areas may notice more dust than usual, but it will diminish, enough to not affect air quality for a prolonged length of time.

The Sedona Fire Department has been involved with the Uptown Parking Garage Project since 2022 and will issue controlled rock blasting permits for this project during the scheduled blasting window. Both the Fire and Police Departments have been notified and are involved as this project progresses. A Fire Marshal will be present when controlled rock blasting operations occur.

A Fire Marshal will be present during each scheduled controlled rock blast, and rigorous pre-blasting preparations will take place to ensure nobody is hurt during these operations.

To learn more about controlled rock blasting, click here. To learn more about this project and blasting, please visit our Project Details page or call our Project Hotline at 928-852-4164. To receive regular project updates, email a request to info@uptownsedonagarage.com.