Corrosion, leaks and breaks in old-technology pipe materials are degrading our water delivery and sewage treatment systems, which are critical to public health and the environment.

According to a 2023 Utah State University report North America experiences 710 water main breaks a day, totaling $2.6 billion in annual repair costs. This doesn’t include the high costs of emergency equipment, depleted water supply, traffic disruptions, and lost work time. Experts note that corrosion is the leading cause of this water main break epidemic.

Corrosion is a significant drag on the economy, costing U.S. drinking water and wastewater systems over $50.7 billion annually, or more than $1 trillion dollars over the next twenty years. Not only is this cost calculated in terms of water main break repair, but also in terms of lost water, replacement of corroded pipes and implementation of corrosion-mitigation measures, which are ineffective since they only delay an unavoidable outcome.

Today’s corrosion crisis is due to the materials used in America’s underground pipe networks over the last 100 years. At first, cast iron was used, with ductile iron gradually replacing it. Both now suffer from the ravages of corrosion.

The American Society of Civil Engineers has consistently given poor marks to the nation’s public drinking and wastewater systems, saying hundreds of billions must be spent over the next two decades for upgrades and replacements.

Taxpayers are fed up. Local governments are scrambling for solutions.

Tuberculation is a form of internal corrosion and bio-film contamination which develops in iron pipes and restricts water flow. It can be a breeding ground for bacteria.

The town of Walkerton, Ontario provides a case in point. In 2000, E-coli had infiltrated the municipality’s iron-pipe water network, and purging it from the system was extremely difficult. Only after repeated and costly flushing with super-chlorination was the piping system safe to use again.

Unlike iron pipe, PVC pipe is not affected by tuberculation. Its smooth, non-corrosive surface stays clean even after decades. An ISO Standard 14025 Environmental Product Declaration conducted for PVC water and sewer pipe, certified by global health organization NSF International, confirms the safety of PVC water pipe: “No known chemicals are released into the water system. No known toxicity effects occur in the use of the product.”

Today, Walkerton, now part of the Municipality of Brockton, is replacing its iron pipes with PVC. In fact, it’s the only material the community now uses in its water system. Says Colin Saunders, Brockton’s utilities manager, “With PVC pipe, I don’t have concerns about corrosion, tuberculation or water main breaks, and this means lower maintenance costs and a longer lasting piping network.”

It is important to critically examine recycling claims. Ductile iron (DI) pipe manufacturing, which uses metals from recycled automobiles, releases a host of additional chemicals such as lead, mercury, manganese, zinc, chromium compounds, trimethylamine, xylene, methanol and phenol compared to iron pipe made from virgin iron ore. The production of PVC pipe using virgin material is less energy intensive than DI pipe using recycled materials, resulting in fewer environmental impacts for water infrastructure projects. It is therefore critical to review using a life cycle data perspective, which may in fact indicate even greater impacts. When examining embodied energy impacts, the cradle-to-gate stage (raw material supply, transport and manufacturing) of DI pipe production exceeds the embodied energy of the entire life cycle of the equivalent PVC pipe. Moreover, piping materials such as polyethylene (HDPE) and prestressed concrete cylinder pipe (PCCP) also represent greater impacts, even when not accounting for replacement of failed piping systems.

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While certain pipe manufacturers continue to explore “solutions” to corrosion – because their materials are affected by it – PVC remains indisputably resistant to it.

PVC pipe is a proven and extremely durable alternative to traditional corrosion-prone pipe materials. Recognized by state, national and international agencies and standards organizations, it has been a benchmark since it was introduced in the U.S. sewer, water and drainage markets in the 1950s.

Over two million miles of PVC water and sewer pipe are currently in service. A review by Engineering News Record in 1999 found PVC for water and sewer pipe to be one of the top twenty engineering advancements in more than a century.

An American Water Works Association Research Foundation study confirms the life expectancy of PVC pipe to be in excess of 110 years.

PVC’s cost-effectiveness and sustainability are important qualities that city and local lawmakers should be considering–and taxpayers should be demanding.

Life Cycle Assessment of PVC Water and Sewer Pipe and Comparative Sustainability Analysis of Pipe Materials Report

Comparative analysis and environmental review of underground piping shows PVC pipe has fewer environmental impacts and life cycle costs over a 100-year life.

Click here for report.

If carbon output for cradle-through-installation were penalized for 8-inch PVC and ductile iron (DI) equivalent pipes at a functional length of 100 feet, PVC would be ranked lowest at $25 or $35 (depending on pressure class) compared to DI pipe at $225.

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Outdated procurement rules in some municipalities ignore proven materials like PVC pipe. Closing bids to qualified products prevents informed decisions from being made, resulting in higher costs.

“The traditional habit of using one or two pipe materials exclusively is no longer satisfactory, local officials need to compare all proven pipe materials,” says Schenectady (NY) Mayor Brian Stratton, co-chair of the U.S. Conference of Mayors Water Council:

Since pipe is the largest component of a water utility’s assets, it’s critical that steps be taken to ensure its long-term sustainability, which will help utilities hold the line on costs.

PVC is the most cost-effective and durable piping material available today, and procurement practices should be reformed to ensure it helps solve the corrosion crisis in every municipality.

Our country’s underground infrastructure is at a crossroads. The time has come to put an end to the corrosion crisis and include PVC pipe in all municipal bids for underground infrastructure.