Boardwalk Pipeline Partners is a partnership holding company that operates in the midstream portion of the natural gas and natural gas liquids and other hydrocarbons (NGLs) industry, providing transportation and storage for those commodities. At Dec 31 2016, Co. owned about 14,365 miles of natural gas and NGLs pipelines and underground storage caverns. Co.'s natural gas pipeline systems are located in the Gulf Coast region, Oklahoma, Arkansas and in the states of Tennessee, Kentucky, Illinois, Indiana and Ohio. Co.'s customers include producers of natural gas, local distribution companies, marketers, electric power generators, industrial users and interstate and intrastate pipelines.