Modular Steel Bridges Reconnect Routes After Flooding in California

The following article and images were provided by Acrow.

Acrow, a leading international bridge engineering and supply company, announced two of its modular steel bridges were installed recently to reconnect flood-damaged routes in different locations within San Luis Obispo County in California’s Central Coast region.

The existing infrastructure was damaged during heavy rainstorms in January and March 2023.

Project #1 – ‘Longer-Term’ Detour Solution (Chimney Rock Road Bridge)

Near the city of Paso Robles in the northern part of the county, storm waters in March washed out three culverts beneath Chimney Rock Road, resulting in an 80-foot-long, 50-foot-deep canyon bisecting the road and cutting off access to neighborhoods and a mining business on the east side of Lake Nacimiento.

Because the route is used by first responders and for evacuation in the event of fire, San Luis Obispo County quickly built a temporary access road, but required a longer-term detour solution.

After excavation of one of the banks to provide access for the launch, the assembly of Acrow’s single-lane modular bridge began in early June. It was installed with a crane-assisted launch and opened to traffic at the end of June. The modular bridge is expected to be in place for several years until a permanent crossing is designed and constructed.

The 170 feet (51.8m) long single-lane Chimney Rock Road Bridge is expected to be in place for several years until a permanent crossing is designed and constructed.

Chimney Rock Road Bridge Details:

• 170 feet (51.8m) long
• Single-lane bridges
• Designed to AASHTO HL-93 loading
• Curb-to-curb dimension of 13.8’ (4.2m)
• Epoxy aggregate decks
• Delivery of the components to was difficult due to narrow, winding roads over damaged roads
• Rented to Souza Construction, Inc., of San Luis Obispo (installation contractor under contract to San Luis Obispo County)

Project #2 – Emergency Route Restored (Townsite Bridge)

The second installation took place in the small community of Huasna in the southern part of the county, where the bridge over the Arroyo Grande Creek on Huasna Townsite Road was snapped in half by floodwaters in January.

Although the 70-year-old bridge had recently been approved for replacement, the road and structure are an important emergency route in and out of the remote Huasna Valley, so restoring the route as quickly as possible was critical. In addition, the route connects Huasna with several large ranches and National Forest lands.

Assembly of Acrow’s modular steel bridge began in early July. The bridge was installed with a full cantilever launch and opened to traffic in early August. It is anticipated the structure will be in service for three or more years while a permanent bridge is designed and built.

The 180 (54.86m) foot long single-lane Townsite Bridge will be in service for three or more years while a permanent bridge is designed and built.

Townsite Bridge Details:

• 180 feet (54.86m) long
• Single-lane bridges
• Designed to AASHTO HL-93 loading
• Curb-to-curb dimension of 13.8’ (4.2m)
• Epoxy aggregate decks
• Delivery of the components to was difficult due to narrow, winding roads
• Rented to Souza Construction, Inc., of San Luis Obispo (installation contractor under contract to San Luis Obispo County)

Acrow Provides Components Quickly and Economically

“We are honored to have been part of these important emergency projects to restore transportation lifelines to impacted communities,” said Deon Lourens, Acrow’s business development manager, pacific states. “Easily delivered to the most remote and challenging locations, Acrow’s high-quality modular steel bridges are rapidly assembled and installed and can be designed to serve a wide range of temporary and permanent applications.”

“Acrow’s ability to provide critical bridging components quickly and economically is built upon our decades of experience in restoring transportation infrastructure in emergency situations across the globe,” added Bill Killeen, CEO of Acrow Bridge. “Available for rent or purchase, our proven solutions serve the needs of departments of transportation and contractors alike.”