HDPE Pipe Vulnerable to Disinfectants in Potable Water Mains

Several articles published in December 2019 and January 2020 report on the premature failures of HDPE piping in Hamilton, OH 1, 2, 3. As a result of these failures, the City of Hamilton will replace more than 20 miles of HDPE pipes after only 20 years of service, some 60 years earlier than expected.

The premature failures reflect the vulnerabilities of HDPE pipes. In Hamilton, it was the deleterious reaction of the pipe material with the disinfectant the city has used since 1972. HDPE vulnerability to disinfectants has been well-documented 4, 5. There are distinct advantages to using ClO2 as a disinfectant. It controls a broad-spectrum of microorganisms while preventing the formation of disinfection by-products and controlling taste and odor of the water – one reason Hamilton has won so many local, national and worldwide awards for its outstanding taste.

The decision to use HDPE pipes was made in the 1990s “to save money,” according to John Bui, Hamilton’s water production superintendent. Had they known of the extreme vulnerability of the pipe to disinfectants, “…we wouldn’t have used HDPE pipes in our distribution system…”

At the time of their installation, the HDPE pipelines were regarded as being the pipe of “the future.” Unfortunately, that future arrived too soon in Hamilton, OH. The city has decided to replace the failing HDPE with a pipe that has proven reliability; one with a resilient future - Ductile iron pipe.

 1 Rutledge, M., “Water-treating chemical causing early failure in Hamilton pipes,” Journal-News, Butler County, OH, December 02, 2019, online article retrieved January 27, 2020. 

 2 “Ohio city replacing HDPE pipes after only 20 years,” Plastics News, December 20, 2019, online article retrieved January 27, 2020. 

 3 Rutledge, M., “Plastic pipes led to Hamilton’s natural gas disruptions that displaced customers, closed streets,” Journal-News, Butler County, OH, January 22, 2020, online article retrieved January 27, 2020. 

 4 Choi, B., Zhou, Z. and Chudnovsky, C., “Modeling of Stress Corrosion Cracking in Plastic Pipes,” Proceedings ASCE Pipelines Conference, 2008.

 5 Technical Memorandum, “Evaluating the Compatibility of Chemical Disinfectants with Plastic Pipe Materials Used for Potable Water Distribution,” Corollo Engineers, August 2008.