Failed thermoplastic or corrugated metal drainage systems, from the wild fires in California to the hurricane damage in Texas and Florida, were identified as the primary cause of many road failures. Unlike concrete, thermoplastic pipes will melt and burn. Based on recent fires in California, damage to a thermoplastic drainage system has extended far beyond the damaged pipe itself to include sidewalks, roadway, gas/oil pipelines, drinking water systems and nearby structures. Fires in concrete pipeline systems generally don’t affect structural strength or flow capacity; the two fundamental requirements of a gravity pipeline drainage or collection system.

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This is a demonstration of the comparative flammability of polypropylene pipe (PP), reinforced concrete pipe (RCP), and high density polyethylene pipe (HDPE). Dry hay is ignited in three 18 in. by 18 in. pipes and allowed to burn. This is an unedited test conducted on October 21, 2015.