Construction of the Trans-Alaska Pipeline System for a fifth, should it become necessary. Holding tanks were planned that had a capacity equal to that of the pipeline, allowing the whole pipeline to be emptied if required. As required by the Pipeline Authorization Act, a ballast-water filtration system had to be designed as well. This system removes oil from tankers' ballast water so it is not released into Prince William Sound—something fishermen feared when the pipeline was proposed. Shortly after the permit was signed, convoys of equipment on snow tractors began heading north, using hardened snow roads and an ice bridge over the Yukon River to reach
Natural gas pipeline system in the United States Natural gas pipeline system in the United States The US natural gas pipeline system is a complex system of pipelines that carries natural gas nationwide and for import and export for use by millions of people daily for their consumer and commercial needs. Across the country, there are more than 210 pipeline systems that total more than 305,000 miles of interstate and intrastate pipelines. Of the lower 48 US states, those with the most natural gas pipeline running through them are Texas (58,588 miles), Louisiana (18,900), Oklahoma (18,539), Kansas (15,386), Illinois (11,900) and California (11,770). The states with the least