Introduction
The U.S. natural gas pipeline network is a highly integrated network that moves natural gas throughout the continental United States. The U.S natural gas pipeline network is an intricate transportation system made up of about 3 million miles of mainline and other pipelines that links natural gas production areas, and storage facilities with consumers. This natural gas transportation network delivered more than 24 trillion cubic feet (Tcf) of natural gas during 2014 to about 73 million customers.
What makes up this transportation network?
Transporting natural gas from production areas to consumers involves a series of steps that are generally carried out in the following order:
- Gathering systems, primarily made up of small-diameter, low-pressure pipelines, move raw natural gas from the wellhead to a natural gas processing plant or to an interconnection with a larger mainline pipeline.
- Natural gas processing plants separate hydrocarbon gas liquids, nonhydrocarbon gases, and water from the natural gas before the natural gas is delivered into a mainline transmission system.
- About 302,000 miles of wide-diameter, high-pressure interstate transmission pipelines (pipelines that cross state boundaries) and intrastate transmission pipelines (pipelines that operate within state boundaries) transport natural gas from the producing and processing areas to storage facilities and distribution centers. Compressor stations (or pumping stations) located along the length of the pipeline network keep the natural gas flowing forward through the pipeline system. More than 300 companies operate mainline transmission pipelines.
- More than 1,100 local distribution companies deliver natural gas to end users through hundreds of thousands of miles of small-diameter service lines. Local distribution companies reduce the pressure of the natural gas received from the high-pressure mainline transmission system to a level that is acceptable for use in residences and commercial establishments.
How did this transmission and distribution network become so large?
Did you know?
Natural gas consumers in more than half of the states in the nation depend on the interstate natural gas pipeline system for their natural gas supply.
About 142,000 miles of the current 302,000 miles of the mainline natural gas transmission network were installed in the 1950s and 1960s as consumer demand for natural gas more than doubled following World War II. About half of the natural gas pipeline mileage currently installed in Texas and Louisiana, two of the largest natural gas production areas in the United States, was constructed between 1950 and 1969. By the close of 1969, marketed natural gas production exceeded 20 Tcf for the first time.
Source: Stock photography (copyrighted)
A large portion of the 1.3 million miles of local distribution pipelines that receive natural gas from the mainline transmission grid and deliver it to consumers was also installed between 1950 and 1969. The period of greatest local distribution pipeline growth happened more recently. In the 1990s, more than 225,000 miles of new local distribution pipelines were installed to provide service to the many new commercial facilities and housing developments that wanted access to natural gas supplies.
Natural gas prices, along with oil prices, increased substantially between 2003 and 2008. Higher prices provided natural gas producers an incentive to expand development of existing fields and to begin exploration of previously undeveloped natural gas fields. Consequently, new pipelines have been constructed, and others are being built to link these expanded and new production sources to the existing mainline transmission network. From 2000 to 2014, about 34,260 more miles of distribution pipelines were added to the national transmission network.