Spectra Energy Partners, L.P. through its subsidiaries and equity affiliates, is engaged in the transmission, storage and gathering of natural gas, the transportation and storage of crude oil, and the transportation of natural gas liquids. Its segments include U.S. Transmission, Liquids and Other. The U.S. Transmission business provides transmission, storage, and gathering of natural gas for customers in various regions of the northeastern and southeastern United States. The Liquids business provides transportation and storage of crude oil for customers in the central United States and Canada. As of December 31, 2016, it had over 15,000 miles of transmission and transportation pipelines, and the storage of natural gas in underground facilities with aggregate working gas storage capacity of approximately 170 billion cubic feet in the United States and Canada. It owns and operates natural gas transmission, gathering and storage assets, and crude oil transportation and storage assets.