Wednesday Feb 10 2010
Sky-high retrofit: $71 million overhaul for Placer County’s Foresthill Bridge
By: Gus Thomson, Journal Staff Writer
190,000 bolts. Nearly a million-and-a-half pounds of plate steel. Paint to cover a million square feet. They’re astounding numbers but, then again, you’re dealing with the Foresthill Bridge – a marvel of construction and engineering that has been astounding visitors and Auburn-area residents alike for almost 40 years. The highest bridge in California and third highest in the nation at 730 feet, the county-owned span towering over the American River canyon is about to get a facelift. When workers are projected to start in late this summer, however, they’ll be doing much more than scraping off the rust and graffiti of 38 years to slap on a fresh coat of paint. They’ll also be bolstering its skeleton of steel to bring it up to current seismic stability standards. And the railing that’s now at waist level will be raised to eight feet in height along the two walkways overlooking the American River canyon. Plans for a project that’s expected by county engineers to cost in the neighborhood of $71 million and take until late 2012 to complete were outlined Wednesday. Prospective contractors flocked to a presentation that started with a PowerPoint presentation in North Auburn and ended with a bird’s eye tour of the pea-green bridge. About 60 contractors were escorted through a guano-encrusted, concrete section on one end of the bridge that has become popular with bats. They were soon stepping out onto the bridge’s cat-walk while vehicles rumbled by on a half-mile section of Foresthill Road above them. The catwalk view provided an expansive look at the canyon but also a closer look for contractors at what they have to face. Under plans presented by the county, the work will be difficult, stringent and technically challenging. Project consultant John Quincy explained that the 40-year-old lead-based paint will be taken down to near-bare metal. In some cases, the winning contractor will have to find someone to fit into 2-foot-by-3-foot spaces to remove the paint. And with the environmentally sensitive American River canyon below, the paint removal operation has to be encapsulated in tent-like structures to keep lead and chromium from escaping. Those bats, whose droppings contractors had to avoid in their tour, aren’t nesting at the bridge. But Quincy explained that they do fly inside the concrete structure on the ends of the bridge in the evenings. Contractors will have to find ways to work around the nightly influx without harming them, he said. If high winds take place, workers will have to quickly put all bolts back on and stop work to wait for the storm to die down. There will be temporary lane closures – but cognizant of Foresthill-Auburn traffic at peak periods – actual road closures will be limited to six days. “We’re taking apart a bridge but we’re keeping it open for traffic,” Quincy said. Design work on the retrofit was completed last summer and construction funding from both state and federal sources is expected to be in county hands by next month. The contract could go out to bid in May and construction is targeted to start taking place in August.