Replacing aging pipe remains a big source for work.

Author:Reed, Michael

With so many companies involved in natural gas distribution (P&G) reports on over 300 such companies, ranging in size from 5.9 million to 1,300 customers in the Annual 500 Report in November), this summary of ongoing infrastructure replacement projects is intended strictly as a far-from-all-inclusive overview of current activity.

The 2017 AGA Playbook, released in mid-February, reports that during the past decade local distribution companies (LDCs) have installed updated plastic pipelines at a rate exceeding 30,000 miles per year. The AGA data shows that of over $21 billion of gas utility construction for 2015, $11.6 billion or about 55%, went toward gas distribution assets.

As recently as 2014, the federal Department of Transportation (DOT) estimated 30,000 miles of cast-iron pipe still carried gas in the United States, with the highest percentage of these mains located in older eastern cities such as New York City, Philadelphia, Boston, Baltimore and Washington, D.C.

Further DOT data indicate that replacement work, while steady, is far from complete. In 2015, there were still 27,771 miles of wrought- and cast-iron gas distribution lines in service in the U.S., down from 39,342 miles since 2005, a decrease of almost 30%.

As Lori Traweek, AGA's chief operating officer, described it, "The sheer volume of work being done throughout the country has led to job growth in our industry and a widespread effort by natural gas utilities to recruit and train workers that can install and maintain the infrastructure of the 21st century."

Since 2010, she said, LDC operators have replaced over 20,000 miles of cast-iron and bare-steel pipeline, and about 900,000 miles of cast-iron and bare-steel services.

"All natural gas utilities upgrade and modernize their infrastructure, and 41 states, including the District of Columbia, have specific rate mechanisms that foster accelerated replacement of pipelines no longer fit for service," Traweek explained.

Additionally, DOT data showed that during the period 2004-13, distribution companies replaced 17,000 miles of bare-steel mains, leaving about 56,000 miles of bare-steel still in operation. With that in mind, these summaries show there is still a large volume of work to be done for decades to come through multibillion-dollar infrastructure replacement programs, many now underway nationwide, with more destined to follow.


Washington Gas continues to replace 15,960 miles of mains and over 234,530 gas services as part of its accelerated pipeline-replacement program in Virginia, Maryland and the District of Columbia. The work has been underway two years and will continue, depending on the location, from 15-40 years.

The ongoing work also targets replacement of bare and unprotected steel services, bare or unprotected targeted steel mains, cast-iron, copper and vintage plastic services. In all, 520 miles of cast-iron pipe is being replaced, the majority of it in the District of Columbia.

Most of the replacement pipe will be medium-density polyethylene, the majority of which is 2-inch or smaller.

The company will spend $650 million over the next five years on infrastructure...

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