Columbia Gas Transmission, a unit of NiSource ( NI - Get Report), plans to expand its pipeline, compression and storage networks. The project will expand Columbia's ability to serve growing eastern and mid-Atlantic markets. The project's proposed in-service date is April 1, 2009. Four local gas utilities have executed 15-year agreements for the combined new storage and transportation services. Columbia Transmission operates 12,750 miles of interstate natural gas transmission pipeline in the mid-Atlantic, Northeast and southern states, including 36 natural gas storage fields.