Engineering -Work continues on No. Fork Bridge damaged during 2013 floods

The Arapaho and Roosevelt National Forests and Pawnee National Grassland (ARP) continue work, responding to road, bridge, and other infrastructure destroyed during the September 2013 Flood.

Workers digging in the mud

North Fork Trail bridge cement pour
Two workers with bridge form

Forms for bridge repair cement pourWorkers sit on a cement form for a trail bridge

The ARP continues working collaboratively with Larimer County on several road reconstruction projects to meet the needs of communities and the public to have a dependable and safe road network while meeting the aquatic and riparian resource values of the ARP. Specifically, the ARP expects that the reconstruction of roads will locate infrastructure (embankments, bridges, culverts) where they will be more resilient from damage to future floods and improve the hydraulic capacity and ecological continuity of adjacent streams and floodplains. The ARP provided the Forest Service standards to design and construct all road-stream crossings on NFS Lands to 1) provide for the passage of water, sediment, and wood through the structure, 2) sustain long-term channel integrity through the structure, 3) withstand the design flood and expected sediment and debris during the design life of the structure, and 4) allow for the free movement of fish and other aquatic organisms through the structure. As a result, the County is working with FEMA to incorporate these Forest Service standards into the reconstruction designs of two major road projects.

The North Fork Bridge on the Canyon Lakes Ranger District was destroyed in a flood that affected much of the district. In the late fall of 2015 three Forest Service employees, with the help of Poudre Wilderness Volunteers built the bridge abutments for the North Fork Trail.  The original bid for the work came in at $156k which was over double the engineer’s estimate of $64.9k and it was quickly realized that the only way to get the work done before spring runoff was by our Forest Service employees. These employees succeeded in bringing in a contractor for excavation, rented/bought materials to build the forms, ordered the concrete, and supplied all labor to successfully build the abutments all before the winter snow set in. Total cost to the government was $27.2k which included all materials and salaries for the three Forest Service employees. This resulted in a cost savings of over $37k to the government from the original government estimate (or over $128k savings from the contractor’s bid). This continues to be an ongoing project with the next step to install the prefabricated bridge.