Bridge Crossing

An existing bridge, with a 2-inch gas line crossing, is in need of replacement. How do you address the need for a temporary gas line crossing over a river, while the bridge is under construction? It always comes down to feasibility, construction space requirements, and the inability to shut down the gas line during construction. In this situation, you think outside the box. For this application, never done before, we designed for a 180-ft temporary aerial line crossing. Based upon the flow rate and pressure requirements, we were able to use a 1-inch internal diameter CNG flexible hose, rated for 5000 psig. The installation is similar to the installation of electrical utility lines, using a ½” diameter messenger cable to support the high-pressure hose and double lashing wire to secure the hose to the messenger cable.