“Why would anyone bid this? This is ridiculous!” said one of Q&D’s superintendents on arriving for the pre-bid site walk led by the California Department of Transportation (Caltrans) in late 2018. It was difficult not to see that as an omen when looking down the 900-foot drop-off beneath the Echo Summit Sidehill Viaduct. Folks were wondering what they might be getting themselves into.
They traveled down the winding, narrow, unpaved “path” down a cliff face with a near 1:1 slope to view the support structure of the 79-year-old three-span, reinforced-concrete-and-masonry viaduct joining two sides of a granite cleft over 7,300 feet in elevation in the Sierra Nevada. Above them, traffic on US Highway 50, a major east-west connector route through the mountain range, busily continued.
In addition to the sheer slope, the team noted the rocky and uneven terrain under the viaduct and, atop the girders, the narrow roadway which would surely limit equipment sizes. The bid instructions called for an unusually restrictive timeline, considering the additional challenges posed by the site location, due to the importance of the highway not only to local traffic but for intrastate and cross-country travel. Oh, and then there was ice and snow. With all the constraints, it felt impossible as they quietly listened to the Caltrans representatives talk through the project.
Q&D’s Heavy/Civil Group VP Jeff Bean will tell you he seeks out these uniquely challenging opportunities for his team. “I believe in my team’s abilities. They have proven themselves to be innovative, creative on accelerated bridge construction projects in the past – they push the limits AND they know where to draw the line to keep people safe. Projects like the Echo Summit Viaduct Replacement deter the average builder from even bidding. I know we can win and when we do, that we can also deliver on our promises even under these difficult circumstances and with the high degree of planning and effort required. It’s probably good I didn’t attend the bid walk though. When I got up there to look it over, I had the same reaction as they did on the initial visit.”
To build the new Echo Summit Bridge, Q&D’s team would have to deal with a litany of tough constraints set by the client, the site itself and regulatory restrictions for nearby Lake Tahoe. They included: a dangerous, narrow and steep site along a cliff; closure availability severely limited by local tourism, community travel and environmental regulations; severe snowy winters; federal, state and local environmental regulations around Lake Tahoe; safety of residents and tourists in the valley below the site; an aging existing structure of relatively unknown structural performance with as-builts from 1939; procurement delays; fire danger; low visibility due to smoky conditions, and; the COVID-19 global pandemic.
In order to overcome the challenge of the narrow site, and limited choices for equipment, the team developed a plan for a tandem lift of each girder which allowed for smaller cranes on each abutment in lieu of a single large crane. Even using this approach, the crane on the north abutment had less than ½” of clearance to trees growing in the cliff on the uphill side. Each girder was delivered on tractor / steerable dolly combination trucks which had less than 2” of clearance between the crane’s outriggers (pulled all the way in), and the existing face of the bridge rail.
The scope of the project was complex even when executed on a fairly flat grade. Combined with the extreme site conditions, it became magnitudes more dangerous for workers, travelers and residents. Crews completed the project with no incidents and no lost-time injuries over the course of more than 25,000 worker hours.
Q&D overcame the intense challenges by finishing early, without unexpected or unscheduled closures, while protecting the unique history and character of the region and with a perfect safety record. “When we turned in our number,” said Bean, “I had the feeling Q&D was the only company that SHOULD bid this project. Now that we are successfully complete, and I have seen the hard work and tenacity it took to get it done, I am not sure anyone else could have done it.”
“It was amazing to watch,” continued Bean of the team camaraderie and positive attitude. “In that closure period, everyone was playing their part – almost synchronized – in spite of the 12-hour shifts, multiple crews, night work and high degree of hazards on the project. To a person they rose up to meet the challenges to perform the work, and even improve on our strategies. I am really proud of this team. We have accomplished a lot together over the years and I am happy to add this to our list of unique and amazing – legendary – projects.”
El Dorado County, CA