A pipeline by any other name…is still a pipeline. But the industry divides the nation’s approximately two million miles of oil and natural gas pipeline into three categories: gathering, transmission, and distribution.

Gathering
The journey starts with gathering lines. They transport crude oil or natural gas from the wellhead to a central collection or storage point. Gathering lines are smaller in diameter than transmission pipelines, and generally operate at low pressures and flow volume. Both gathering, with specific exceptions, and transmission pipelines are regulated by the Pipeline and Hazardous Materials Safety Administration (PHMSA).

Transmission
The next step in the transportation process is getting the crude oil or natural gas from the collection point to oil refineries, natural gas processing facilities, and chemical plants. That’s the job of transmission pipelines, which also transport the refined or processed product from those locations to storage facilities and distribution networks.

Transmission pipelines can range from several inches to several feet in diameter, and in length from a few hundred feet to more than a thousand miles. Depending on the product being transported, the pipeline can be operated at pressures of more than 1,000 pounds per square inch.

Most transmission pipelines are operated remotely from a computerized control center. Operators there can start and stop pumps, open and close valves, monitor product movement, and detect leaks.  Data observed at the central control center is often confirmed with on-site field personnel.

Distribution
The journey ends with distribution lines. Within the realm of oil pipelines, distribution lines bring gasoline, diesel fuel, and heating oil to wholesale distributors. In most cases, those products are then delivered by truck to retail customers, such as gas stations and homes.

For natural gas, the point where the large transmission pipelines connect to a local distribution system is known as the city gate. There the pressure is lowered and a sour-smelling odorant is added to the gas to help consumers detect even small leaks.

Natural gas distribution lines are relatively small and many are constructed of plastic. Main lines and service lines are installed along and under streets, and to individual homes and buildings.

It is through this vast, safe, and reliable network that pipeline operators deliver the energy we need for the life we want.