National Span Trinity Bridge Project

· Project Name: Trinity County Bridges, Six Rivers National Forest, South Fork of Mad River

· Location: N40 deg 09.764’ W 123 Deg 13.615’… Approx 7 miles south of Ruth, CA

· Contract Number: DTFH68-11-C-00011

· Project Number: CA PFH 149-(3) Site 5

· Owner: Six Rivers National Forest, Trinity County, CA

· Contractor: Hooker Creek Construction, Red Bluff, CA

· Bridge Supplier: National Span, Rohnert Park, CA 800-581-1278 www.nationalspan.com

· Engineer: National Span & Jacobs Engineering

Project Description:

The Federal Highway Administration worked with Jacobs Engineering and National Span to develop a solution for three structural deficient and functionally obsolete timber bridges in the Six Rivers National Forest. The South Fork Mad River project is a bridge replacement using a 54’ precast concrete arch structure on cast-in-place spread footings. The Van Horn Gulch crossing used a 60’ Precast Arch and was installed on October 8, 2012 and the Shanty Creek crossing will use a 54’ Precast Arch and will be installed in the Spring of 2013.

National Span Precast Arch Structure provided the lowest installed cost and lowest life cycle cost of all options considered. The Precast Arch Structures are buried structures which minimize or eliminate future structure and bridge deck maintenance.

Technical Description:

· Span: 54’

· Rise: 10’

· Overall Length: 40’

· Precast Headwalls: 2

· Installation Date: October 11, 2012