Overview | Energy Transfer



The Mariner East pipeline system provides the needed infrastructure to transport propane, ethane and butane, all known as natural gas liquids (NGLs), from the Marcellus and Utica Shale fields to markets in Pennsylvania and beyond.

SP20 239650 MarinerMap 2 - Overview

Mariner East 1

Mariner East 1 is an existing eight-inch pipeline that was improved and refitted for the transportation of ethane and propane. Energy Transfer built a new, 50-mile section to the beginning of the line in western Pennsylvania for added connectivity. The Mariner East 2 and 2X pipelines predominantly follow the existing Mariner East 1 right-of-way across Pennsylvania.

Mariner East 2

The Mariner East 2 pipeline was put into partial service in December 2018. The pipeline is expected to be fully in service in Q3 2021.

Mariner East 2X

Our Mariner East 2X pipeline, which parallels Mariner East 2, was put into partial service in Q4 2020. The pipeline is expected to be fully in service in Q2 2021.

End markets

The Mariner East system will connect along its route to a new power plant in Cambria County for ethane feed, as well as two local area propane and butane distribution terminals. The system is also playing a major role in repurposing the Marcus Hook Industrial Complex as the preeminent hub in the northeastern United States for distribution of these natural resources to domestic and global markets.

Propane, butane and ethane are products of natural gas development. They are gases that come out of the ground with traditional natural gas (methane) and are shipped in liquid form; that’s why they are called natural gas liquids. Propane is used to heat homes, businesses and farms, ethane can be used as a fuel for power generation, and butane is a component of gasoline. All three are used as basic feedstocks for making plastics, coatings, clothing and a host of other products we use every day.

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The Natural Gas Chain

SP20 255250 NatGas Chain Butane 1b - Overview
SP20 255250 NatGas Chain Ethane 1b - Overview
SP20 255250 NatGas Chain Propane 1b - Overview