What gives? Raleigh's 252 water main breaks in a year considered low

RALEIGH, North Carolina (WTVD) -- Fresh off another huge repair effort, managers at Raleigh's water utility want to reassure residents that the area's infrastructure is on solid ground.

"In most cases they're not necessarily a big problem-causing type issue where they cause road damages and road closures," Ed Buchan, Raleigh Public Utilities Environmental Coordinator, told ABC11. "These are pressurized pipes, so these are bound to happen."

Tuesday's gush flooded parts of Capital Boulevard; officials say that pipe was made of cast iron and dates back to the 1960s. Most pipes nowadays are made of fiberglass or ductile iron.

"We hope to get roughly 75-100 years to underground pipe that we have," Buchan added. "However, it's material dependent. Some pipes were installed in the 50s and 60s that we recognize now were of poor quality."

In total, Raleigh Public Utilities manages more than 2,500 miles of water main pipes, or about the distance between Raleigh and Los Angeles. The average age of the pipes is 30 years old, but that balances the older pipes (pre-World War II) and miles of new pipes for each new neighborhood and development.

In total, crews repaired 252 water main breaks during FY 2016-2017, an average of 21 per month - but those numbers may be misleading because of the length of the pipes combined.

According to the American Water Works Association, Raleigh averages 9.34 water main breaks for every 100 miles, and that's very low in the context of the national average, which is around 31 per 100 miles of pipe.

Ed Buchan, Raleigh's Environmental Coordinator, says several of those have been caused by construction, such as the underground installation of Google Fiber and AT&T cables, and not necessarily due to erosion.