Roads and Bridges Magazine recently selected the 1,421footlong Nigliq Channel Bridge as one of its Top Bridges of 2016. CH2M provided construction and logistics support on the Nigliq Channel Bridge, which earned the second spot in the magazine’s list of top 10 bridges in the country.
The bridge, completed in 2015, provides access to the Alpine satellite CD5 drill site on the North Slope of Alaska, and comprises eight spans up to 200 feet long and provides access for heavy oil field service vehicles weighing up to 175 tons. CH2M served as the major construction subcontractor for pier pilings.
Our experience working in the challenging North Slope conditions provided the project team with key best practices to ensure smooth operations during construction, including keeping the large array of cranes, trucks, and other bridgebuilding equipment running effectively. We supported the over 400 workers on the project, keeping all equipment fueled and running 24 hours a day, 7 days a week.
Throughout construction, the team faced numerous challenges, including the bridge’s remote location and extreme climate, with temperatures as low as 45°F and wind chills reaching 65°F, as well as blizzards, limited infrastructure, extended arctic darkness, and limited access due to lack of permanent roads and seasonal ice road restrictions. In fact, given the far north location, the team needed to time the construction season perfectly with the coldest part of the year, when ice roads could be built and maintained (typically from midJanuary to late April).
Engineered to support six pipelines along its downstream side, protecting them against ice floes up to 6 feet thick and 200 feet wide, the Nigliq Channel Bridge is the first and longest “launched” bridge constructed in North America north of the Arctic Circle. “Launching” the bridge, or prefabricating the structure offsite and then transporting it to its final location, minimized the project’s environmental footprint and maximized safety by reducing work at height by 50,000 labor hours as opposed to standard construction methods.