Our Transportation segment operations generally consist of fee-based activities associated with transporting crude oil and NGL on pipelines, gathering systems, trucks and barges.

Revenue

Transportation revenue is generated through a combination of tariffs, pipeline capacity agreements and other transportation fees. The transportation segment also includes equity earnings from our investments (ranging from 20% to 65%)  in entities that own transportation assets.

Assets

As of December 31, 2018, Plains employed a variety of owned or leased long-term physical assets throughout the United States and Canada in the transportation segment, including approximately:

17,965 miles of active crude oil and NGL pipelines and gathering systems
31 million barrels of active, above-ground tank capacity used primarily to facilitate pipeline throughput and help maintain product quality segregation
50 transport and storage barges and 20 transport tugs
830 trailers (primarily in Canada)