NOAA Scientific Support for a Natural Gas Pipeline Release During Hurricane Harvey Flooding in the Neches River Beaumont, Texas

Abstract

During the height of historic flooding from Hurricane Harvey's rainfall, a rupture occurred in a 16-inch, 80 psia (65 psig) natural gas pipeline crossing the Neches River east of Beaumont, Texas. Over the preceding five days, Hurricane Harvey stalled over the area, generating rainfall totals between 35 and 60 inches. The storm broke the record for rainfall totals in the U.S., with 60.58 inches reported in Nederland, Texas and 60.54 inches near Groves, Texas. The Neches River was in extreme flood conditions, cresting the day after the pipeline rupture at a historic high of 19.59 feet (nearly 10 feet above major flood stage and nearly 7 feet above the former historic record from 1994). At the request of the U.S. Coast Guard Marine Safety Unit (MSU) Port Arthur, NOAA's Emergency Response Division provided scientific support for the incident including on-scene support from the NOAA Scientific Support Coordinator (pre-deployed in Port Arthur, Texas for disaster response) as well as technical assistance from the NOAA Scientific Support Team in Seattle and Baton Rouge. Products and support provided by NOAA included air hazard modeling using ALOHA (Areal Locations of Hazardous Atmospheres) as well as the overall hazards assessment. ALOHA modeling indicated that several significant ignition sources were located within the specific threat zone identified. However, no ignition occurred and no injury or further damage resulted from the release. This incident highlights the advantages and limitations of using ALOHA to model a subsurface natural gas release from a large underwater pipeline provided in the context of an ongoing response to historic flooding and high intensity search and rescue and emergency port operations resulting from a natural disaster.