Water and sewer infrastructure are often taken for granted. A turn of the faucet or a flush of the toilet results in water flowing, and that’s the end of it, as far as many are concerned.
But buried underground, a complex system of pipes and lines shoulders most everyone’s everyday water needs. Many of those pipes are decades old. Some of them weren’t installed properly to begin with. Durango Public Works is stressing that infrastructure needs attention.
Laura Rieck, Public Works spokeswoman, said last month alone city crews made three emergency water main line repairs and four emergency service line repairs.
Referencing the old adage that a picture is worth a thousand words, Rieck said she’s taken that idea a step further in bringing pieces of damaged pipe to Durango City Council chambers in a show-and-tell format to drive the message home.
At a study session with councilors Oct. 1, she plopped a couple pieces of water pipe down on the dais for councilors to inspect. A notable piece of pipe was a 14-inch valve extracted from the ground near the roundabout connecting Goeglein Gulch Road, Fort Lewis Drive and North College Drive.
She said crews oversaw the replacement of the valve, which was discovered to be leaking during another water break.
“They responded to several water breaks, one of which was at the Mercy Housing (Valle de Merced) on Goeglein Gulch Road where a relatively young pipe blew out with a silver dollar-sized hole. … That pipe is only 24 years old. They should last 70 to 100 years.”
When the pipe was unearthed, crews discovered it had been embedded in native, clay-rich soils instead of proper bedding materials, such as pea gravel, she said. Moisture gathered in the clay around the pipe, which led to erosion of the iron pipe and a concrete liner within the pipe.
“If you get one teeny little, no joke, pin hole, and the water starts going through it, it will erode that pipe away. It'll cavitate,” she said in an interview with The Durango Herald.
She said ductile iron pipes should last 100 years. But that’s dependent on proper installation.
Concrete liner is a useful feature inside iron pipes because it prevents tuberculation, mineral buildup caused by water flowing through the pipe, she said. She showed a piece of steel or iron pipe removed March 6, 2018, at West Third Avenue and 22nd Street.
Clumps of corroded material are visible throughout the pipe.
“This is tuberculation, and on the inside of the pipe, (it) builds up and builds up and builds up like a clogged artery,” she said.
She said Public Works’ current standards require pipes to be embedded in pea gravel or similar materials that drain moisture away from the pipes. But the city’s inventory of piping isn’t necessarily up-to-date.
She recalled a previous emergency water break where crews couldn’t shut off a line and couldn’t drain another section of pipe because the valve to that section was broken. The crews, relying on old mapping data, were prepared to replace a 14-inch valve. They purchased the parts, which were shipped from out-of-state. When they dug down to the pipe, they discovered the valve was actually a 12-inch valve. Their data was wrong.
“We try to be as prepared as possible when we actually get in the ground,” she said.
But last-minute orders can take months to fulfill. Things are only exacerbated during wintertime, she said. During freeze and thaw cycles, the ground shifts. That affects water lines.
“If you have a ground shift because of freeze-thaw, then maybe the pipe just got guillotined, or it's got a longitudinal crack, or that little pinhole finally popped,” she said.
The city uses cast iron, ductile iron and plastic PVC pipes across its water system, she said. Some communities use HDPE pipe (long, black piping typically welded together before laid in the ground as one whole piece), but the city doesn’t. And it requires developers to use materials the city can maintain.
But it’s hard to say what standards were in place decades earlier when a lot of water infrastructure was installed, she said.
She said there are three important things to keep in mind when considering the city’s water infrastructure and its future: Aging infrastructure, deferred maintenance and asset management.
She said a proper inventory of the city’s water infrastructure will prevent reactionary maintenance and deferred maintenance – delayed repairs or replacements for the sake of saving money or prioritizing other projects.
The water lines beneath downtown Main Avenue and Durango’s central business district are most urgently in need of repair, she said.
The subject is a factor in the city’s public discussion of its Downtown’s Next Step project, a proposal to install curb extensions, widen sidewalks and make downtown a more pedestrian-friendly space. Although many business owners have objected to the idea of reshaping Main Avenue, city officials have been adamant utility upgrades are needed sooner rather than later and they must be done regardless of short-term construction impacts.
Rieck said water and sewer infrastructure are easily forgotten. They are buried beneath the city, out of sight and out of mind. But she compared water lines to city parks in the sense that if a beloved community park sat for 100 years without any maintenance, it would be a huge issue to the public.
“You don't think about what happens before you turn on the tap and the water comes out,” she said. “You don't think about the journey that it's been on, right? And you don't think about what happens after you hold the toilet, it just goes away, and it's not your problem.”
She said it’s Public Works’ job to make water infrastructure and everyday use seamless to the public. But some awareness and appreciation of the issues of aging infrastructure at hand is required to get the ball rolling toward solutions.
cburney@durangoherald.com
