Seventy-five years ago, the city of Phoenix was about to embark on its first population boom. Now, a lot of the water and sewer pipelines installed during that time are nearing the end of their usable life.
Pipeline averages a life expectancy of about 75 years but can range from 50 to 100. Operating on that average, Phoenix Water Services Department staff forecasted the city will need to spend $20.9 billion over the next 75 years to rehabilitate or replace the more than 12,100 miles of water and sewer pipeline in the city.
However, a lot of that spending will have to come on the front end of that 75-year period. About 41% of the city’s pipelines were built between 1950 and 1980 during the peak years of the city’s population growth. Those pipes will begin to age out from 2025 and 2055.
“These pipelines will contribute to an increasing number of water main breaks as the mains age and begin to fail,” Deputy Water Services Director Darlene Helm told the Phoenix Transportation, Infrastructure and Planning Subcommittee in its Oct. 16 meeting. “To maintain our current service levels, over the next 30-40 years as the infrastructure dating from those peak growth years continues to age, investment in pipe replacement must correspondingly increase.”
Water Services Director Troy Hayes said it will be important to spread out that infrastructure cost over the years. The department will try to balance funding that critical infrastructure with keeping water rates affordable for residents, Hayes said. Bonds are another method by which the city can fund those capital projects.
Water Services staff did not say if rate increases would be needed to pay for the infrastructure costs.
Councilmember Laura Pastor suggested the department could do a better job explaining to residents that the money they pay goes to good use.
“That fee goes to this,” Pastor said.
Though these repair happen on a roughly 75-year cycle, Pastor reminded that Phoenix is in the middle of another population boom.
“Now we are growing, and there will be future infrastructure that needs to be built. And so that will be a whole ‘nother conversation, and that will be a whole ‘nother cost,” Pastor said.
The Water Services Department is routinely assessing and maintaining pipelines, but no pipe lasts forever.
“No matter how well we maintain our assets, they will eventually reach the end of their useful life,” said Nazario Prieto, Assistant Water Services Director.
A break in a water main usually has a short-term impact to residents while it is repaired. Whether or not a pipe is replaced involves consideration of how often it has breaks, the pipe age and material type and the soil type.
In general, a pipeline is considered at the end of its useful life when it becomes too costly to operate or the impact of breaks to customers becomes unacceptable. Phoenix’s goal is less than 14 breaks per 100 miles of pipe.
Helm said their assessment of pipes gives them priorities and they will usually plan a project in a neighborhood to address several mains at once, usually on a half-mile grid.
Sewer pipes are assessed via video every 8-10 years and rated on a nationally standardized system, taking into account age, material and defects of the pipes.
Hayes stressed the importance of assessing water and sewer pipes to keep costs as low as possible for infrastructure replacement.
“[We want to] make sure that we’re not out replacing pipe that still has a good 10 or 15 years left — or even, conversely, out replacing pipe that should have gotten replaced, you know, 20 years ago or so,” Hayes said.
One cost-saving benefit that has developed over the years, Hayes said, is that in the 1970s or ‘80s, it was routine to dig up a pipe every time it needed repair or replacement. The industry standard is now to line the pipes with new material, which saves the cost of digging it up and causes less disruption of traffic.
We’d like to invite our readers to submit their civil comments on this issue. Email AZOpinions@iniusa.org. Mark Carlisle can be reached at mcarlisle@iniusa.org.
Mark Carlisle
Associate Editor | Phoenix
mcarlisle@iniusa.org
Meet Mark
Mark Carlisle joined Independent Newsmedia, Inc., USA, in 2017, covering Glendale. He has since moved to the Daily Independent team, primarily covering the city of Phoenix along with other topics affecting the Valley at-large.
Community: Mark enjoys taking his two young sons to parks, the Phoenix Zoo, the Phoenix Public Library and other fun events around the Valley. He also participates in a local book club.
Education: Chapman University with a BA in English Journalism and one in Screenwriting.
Random Fact: Mark worked at a tuxedo shop in college. Just don’t ask him to tie a bowtie.
Hobbies: Spending time with his wife, sons and dog, watching sports and TV shows, listening to audiobooks and occasionally writing fiction or designing a board game.
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