Main breaks 101: Raising our infrastructure GPA
With a significant portion of our system installed right after World War II, Denver Water is no stranger to main breaks — as Denver witnessed in late January when a nearly 130-year-old pipe ruptured in the Highlands.
An estimated 10 million gallons of water was lost when the 24-inch-diameter pipe burst.
These unfortunate situations are a part of operating a water system, and we’re not alone.
In Denver, we’re working hard to limit these issues and help raise the GPA of the nation’s water infrastructure.
Check out the curriculum for Main Breaks 101:
Home Room — The basics.
Denver Water operates and maintains more than 3,000 miles of pipe — enough to stretch from L.A. to New York. The pipes that carry clean drinking water to your home vary in size, from ½-inch-diameter service lines to a 108-inch-diameter conduit.
Cracks and breaks occur based on the condition of the pipe and its surroundings — including age, pipe material, how corrosive the soil is, water flow, temperature and more.
“Every main break is different, but fixing it safely and quickly are always our top priorities — to minimize disruption to our customers who live, work or commute in the area, and to make sure we lose as little water as possible,” said Tom Roode, Denver Water’s chief operations maintenance officer.
Accounting — Water lost.
Denver Water treats more than 60 billion gallons of water a year, and estimates that less than 1 percent of that water is lost to breaks and leaks we find and repair.
“While water loss due to undetected leaks and main breaks is inevitable, our goal is to proactively locate those leaks and respond quickly to water main breaks across our system,” said Roode.
Math — Calculating water lost.
How do we know how much water is lost through main breaks and leaks? Without a water meter attached to a main break — which isn’t a viable option — we have to rely on calculations that factor in the size of the pipe, cause of the break, average flow rates and average water shut-off times. Here’s how some of the numbers break down:
- ¾-inch service line leak = 15,000 gallons
- 6-inch main break = 30,000-156,000 gallons
- 8-inch main break = 35,000-252,000 gallons
- 12-inch main break = 45,000-378,000 gallons
- 16-inch main break = 52,000-1,125,000 gallons
Applied Science — What we’re doing about it.
To minimize water loss, Roode said Denver Water has numerous programs in place to proactively identify and minimize leaks, and upgrade and repair the aging water system, including:
Leak detection — This program has saved an estimated 138 million gallons of water over the past 5 years. Underground (non-surfacing) leaks found through our leak detection program account for about 0.03 percent of our treated water.
- Pipe replacement — We proactively install or replace an average of 60,000 feet of pipe throughout our service area per year. In 2016, about $11 million went to main replacement and main improvement. Denver Water will invest about $130 million in main replacements over the next 10 years.
- Pressure regulating valve maintenance and replacement — This program allows us to replace or repair the valves that regulate the 160 pressure zones in our system, reducing the number of main breaks caused by these valves.
- Corrosion control — We have more than 4,000 test sites on pipes throughout our system to help us calculate the rates of corrosion and decide which pipes need to be replaced before they cause major damage.
Homework — How can you help?
You already do! Your water rates fund the programs to maintain, upgrade and replace our aging system, helping us ensure we provide you and the 1.4 million people we serve with clean, safe water every day.
If you see what may appear to be a leak in the street, give our emergency dispatchers a call at 303-628-6801.