Introduction and Background

Introduction
To illustrate the progress pipeline operators are making in the replacement of aging gas distribution pipelines, PHMSA now provides access to an annually-updated online inventory that lists high-risk pipeline infrastructure mileage by state. Specifically, the dynamic inventory highlights efforts to replace pipelines constructed of cast or wrought iron and bare steel.

The online inventory allows users to view up-to-date information detailing replacement efforts from 2004 to the present, including the amount of cast or wrought iron and bare steel pipelines in use per state or pipeline operator.

Background
Pipeline transportation is the safest and most cost-effective way to transport natural gas and hazardous liquid products. As America continues to develop and place more demands on energy transportation, it becomes more necessary to invest in upgrading its infrastructure, including aging pipelines.

In January 2012, President Obama signed the Pipeline Safety, Regulatory Certainty, and Job Creation Act of 2011, which provides the regulatory certainty necessary for pipeline owners and operators to plan infrastructure investments and create jobs. For updates on the states’ progress, contact information and incident and mileage data, visit PHMSA’s state pipeline profiles.

In 2011, following major tragic natural gas incidents, Transportation Secretary Ray LaHood and PHMSA issued a Call to Action to accelerate the repair, rehabilitation, and replacement of the highest-risk pipeline infrastructure. Among other factors, pipeline age and material are significant risk indicators. Pipelines constructed of cast and wrought iron, as well as bare steel, are among those that pose the highest-risk.

About Cast and Wrought Iron Pipelines
Cast and wrought iron pipelines are among the oldest energy pipelines constructed in the United States. Many of these pipelines were installed over 60 years ago and still deliver natural gas to homes and businesses today. However, the degrading nature of iron alloys, the age of the pipelines, and pipe joints design have greatly increased the risk involved with continued use of such pipelines.

The Pipeline Safety, Regulatory Certainty, and Job Creation Act of 2011 calls for DOT to conduct a state-by-state survey on the progress of cast iron pipeline replacement. For updates on the states’ progress, contact information and incident and mileage data, the public should visit PHMSA’s state pipeline profiles.

The amount of cast and wrought iron pipeline in use has declined significantly in recent years, thanks to increased state and federal safety initiatives and pipeline operators’ replacement efforts.
Some states have completely eliminated cast or wrought iron natural gas distribution lines within their borders, including Alaska, Arizona, Hawaii, Idaho, Montana, North Dakota, New Mexico, Nevada, Oregon, South Carolina, Utah, Vermont, Wisconsin, and Wyoming.

Approximately 97 percent of natural gas distribution pipelines in the U.S. were made of plastic or steel at the end of 2011. The remaining 3 percent is mostly iron pipe.
To review incidents and the National Transportation Safety Board’s recommendations regarding cast or wrought iron pipelines, visit the Cast and Wrought Iron Pipeline Inventory. 

About Bare Steel Pipelines
Uncoated steel pipelines are known as bare steel pipelines and while many of these pipelines have been taken out of service, some of these pipelines are still operating safely today. The age and lack of protective coating typically makes bare steel pipelines of higher risk as compared to some other pipelines and candidates for accelerated replacement programs.

Over the years, various pipeline protective coating systems have been developed with materials such as coal tar, asphalt, and wax. However, some transmission and distribution pipelines were installed without protective coating until 1971, when federal regulations mandated them on new pipelines.

The Pipeline Safety, Regulatory Certainty, and Job Creation Act of 2011 provides the regulatory certainty necessary for pipeline owners and operators to plan infrastructure investments and create jobs, which includes rapidly replacing remaining bare steel pipelines.