2019’s Museum Fire burned 1961 acres of timber on the steep slopes of Flagstaff’s Mt. Elden. Due to anticipated risk to the Forest and public (including the potential for severe flooding and debris flows in Flagstaff), a BAER (Burned Area Emergency Response) team was assembled after the fire to identify risk and make recommendations to mitigate.
Part of the team’s recommendations included installing a total of five Cable Woven Articulating Concrete Block (ACB) water crossing structures at critical drainage crossings located on Forest System Road (FSR) 557 (Elden Lookout Rd). These structures will provide road embankment protection during rainstorm and debris flow events predicted to be higher than historical intensity and volume due to post-wildfire watershed behavior.
Arizona Surveying was commissioned to utilize laser scanning and GPS to provide survey control and collect topographic field data which helped engineers with design/placement/sizing of the ACB system.