Roads and bridges, airports, energy systems – all are types of infrastructure that we depend on daily to bring functionality to our lives. Yet one of these infrastructures, concrete roadway, lasts, on average, just half our lifetime before becoming worn, riddled with potholes and in need of resurfacing. Hidden beneath our feet, however, is a durable product that plays a more vital role than all of these combined: Gray cast iron and ductile iron pipe make up roughly two-thirds of the nation’s water infrastructure, and they often last hundreds of years.
According to the Ductile Iron Pipe Research Association (DIPRA), more than 600 utilities in the U.S. and Canada have had cast iron mains in continuous service for more than 100 years. At least 21 utilities have iron pipe mains that have now been in continuous service for more than 150 years. Cast iron’s successor, ductile iron, is an equally durable, environmentally-friendly product made from recycled scrap materials that is designed to last for more than 100 years. The durability and sustainability of cast iron and ductile iron pipe are evident in a recent road project in Lancaster, Pa., that involved two 19th-century pipelines.
In late 2012, Don Kirchner, a water distribution supervisor for Lancaster, Pa., was contacted by the Pennsylvania Department of Transportation regarding an 8-inch water main on East Orange Street. The main needed to be taken out of service so the department could lower the elevation on a road that was being resurfaced. The 8-inch main in question ran a distance of seven city blocks on East Orange Street, and fed water to 187 service lines including those for homes, businesses, fire hydrants and six interconnecting streets.
Crews with the Lancaster Public Works Office, which is led by Utility Director Charlotte Katzenmoyer, planned to remove the 8-inch line, along with any segments in the way of the road’s construction. Any pipe left in place would be filled with mortar and the capacity of the 8-inch line would be reconnected to a 20-inch main that ran parallel to the 8-inch line.
“Its durability and dependability are just two of the many reasons that municipalities such as the city of Lancaster recognize the value of installing ductile iron pipe.”
“When we looked at our records, we discovered that the 8-inch main had been installed in 1836,” Kirchner said. “That line had been servicing the Lancaster community for 176 years.”
Records also revealed the 20-inch main had been installed in 1890, more than 122 years ago. According to Kirchner, the 20-inch main was inspected, cleaned and cement lined in 1980 at the age of 90, and it was found to be in excellent condition.
AMERICAN Ductile Iron Pipe Marketing Services Manager Maury Gaston said this project demonstrates the strength, reliability and sustainability of iron pipe. “First of all, the 8-inch pipe lasted almost 180 years, and second, it was still performing when it was taken out of service. In addition, the capacity of the 8-inch line was added to another pipe that was also more than 100 years old, increasing the water pressure in that pipe. I doubt any other pipe material could perform in that manner.”
Ductile iron pipe’s dependability is known throughout the industry and is primarily due to its high strength, durability and ductility, and its impact and corrosion resistance, according to DIPRA. The association also states that ductile iron can withstand the most demanding operating conditions including frozen ground, areas of shifting, and expansive and unstable soils. DIPRA tests have also shown ductile iron’s corrosion resistance is equal to or greater than that of cast iron.
DIPRA President Gregg Horn said his association is proud of the record of iron pipe. “Iron pipe, both ductile and cast iron, have served the water and wastewater industry admirably over the years,” Horn said. “Its durability and dependability are just two of the many reasons that municipalities such as the city of Lancaster recognize the value of installing ductile iron pipe.”
To support this fact, ductile iron pipe was recognized in 2012 as a SMaRT choice for infrastructure development. SMaRT certified products are rated on product sustainability by the Institute for Market Transformation to Sustainability, and ductile iron pipe received the sustainable “gold” rating. This rating is based on numerous criteria including environmental safety, energy reduction and use of recycled materials. The city of Lancaster’s water system is one of many infrastructures in the nation that has uniquely benefited from the sustainability of iron pipe.