Why Water Mains Break

One of the biggest concerns for water utilities during extremely hot or cold weather is water main breaks. Water mains are expected to last a long time – as long as 100 years in many cases. But with many miles of pipe buried underground, it’s reasonable to expect a particular section of pipe will fail or break at some point. The challenge for water utilities is to work proactively to minimize the number of breaks and to respond effectively when a main does break.

While the oldest water mains were made of wood, by the late 1800s, a variety of iron pipe was being used to construct water distribution systems. Common iron varieties included cast and galvanized in the early part of the 20th Century, with galvanized used primarily for smaller diameter pipe. Cast iron pipe was used until the late 1950s when stronger, more flexible ductile iron pipe became common. Plastic pipe, including Polyvinyl Chloride (PVC) and High Density Polyethylene (HDPE) became common in the 1970s. The primary difference between these two plastic pipes is that PVC is stiffer than HDPE, which is more flexible. Even though pipe is expected to last for decades, that doesn’t mean it won’t break at some point. While it is impossible to predict specific pipe breaks, we know that environmental conditions are a major factor in water main breaks.

In the northern and northeast areas of the country where winters are more extreme, cold soils and cold water combine to add stress to pipes, which can—and often do—result in breaks. Iron, like all metals, contracts as temperatures drop. This problem is more common when the source water is surface water (rivers and lakes). These waters are significantly affected by air temperature and can drop to near freezing in the winter. A temperature difference of just 10 degrees in water or air temperatures can cause pipes to contract or expand. Additional stress inside and outside the pipe occurs as temperatures near the freezing point, making the pipe vulnerable to breakage. Water temperature changes more slowly than air temperature changes so the impact of cold water on pipes can cause breakage to take place as many as a couple days after temperatures freeze. Water systems with groundwater sources (wells) have more stable water temperatures because the water is not affected by air temperatures, and therefore, not as significantly impacted. 

Just as pipes are adversely affected by cold weather conditions, they are also affected by severe heat. In some groundwater systems in the southern and southwestern states, the soils are like sponges and hold lots of water. However, during extended periods of hot temperature when high demands for water increases water withdrawal from the aquifers, the soil becomes very dry. In these conditions, the soil contracts and subsides, pulling away from the pipe and diminishing support for the water main. The absence of support for the main can cause it to break. This particular problem led the City of Houston, Texas to begin to convert its groundwater supply to surface water.

Although older mains are generally more susceptible to breaks, breaks can occur on newer mains. This is most likely the result of improper installation or a manufacturing issue with that particular section of pipe. By examining trends in water main breaks over time, a utility is better able to identify categories of pipe that are more prone to breaks, and thus proactively target that pipe for replacement. Aqua employs such tactics in determining which mains to replace. By the end of 2013, Aqua expects to have spent $170 million of its $325 million capital improvement program on water main replacement and associated work.

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Top 10 Ways to Save Water This Summer

1. Make soup from cooking water. 

Who doesn’t love soup? Better question – who doesn’t love making soup more than a water-conscious superchef? Cooking, steaming, and blanching often leaves whole pots of water that is full of nutrients: throw in some stock ingredients, peas or lentils – whatever you love in a soup – and get cooking!

 

2. Water your lawn or garden from a rain barrel instead of the faucet.

As summer heats up, your garden is probably going to need more and more watering. You could spike your water bill by hooking up the hose or loading up your trusty watering can – or you can take advantage of the free water that literally falls from the sky by setting up a rainwater harvesting system. 

 

3. Ditch the hose for outdoor cleanup.

 

Summer means lots of outdoor work; it’s easy and really wasteful to hose away grass clippings and spilled soil from your driveway or patio. Instead, use an old broom at the end of a project to save water – and money!

 

4. Dehumidifier = Plant Water Machine.

Dehumidifiers are great for damp basements, and as an added perk, they give you a pretty much unlimited supply of instant free water for your plants or garden.

 

5. Wash your farmer’s market haul in a pot, instead of running water.

 

You probably wash fruits and veggies under running water. There’s a better way, and it’s pretty simple: Fill a pot. Wash your goodies. Use the leftover water to give your plants a drink.

 

6. Have a pool? Cover up!

No, we’re not urging modesty here – you do you! – but you should cover your pool when you’re not splashing or lounging. You’ll keep your water free of debris, but most importantly, you’ll keep water from evaporating away, especially on hot summer afternoons!

 

7. Don’t feed the weeds.

 

Healthy lawns and garden plants love a good drink. Unfortunately, so do weeds – and they’ll fight your plants for all the water. Getting rid of weeds regularly will keep your plants quenched and happy – plus it’ll save on water that would have been wasted on weeds!

 

8. Defrost frozen meats in the microwave, not under the tap.

If you’re not grilling this summer, you’re doing it wrong. Also doing it wrong: Running frozen foods under water to thaw them. Instead, turn to that king of kitchen efficiency – the microwave! It even has a setting for it and everything.

 

9. Handy with a wrench? Upgrade your shower head/faucet to a WaterSense model.

 

Modern shower heads save water without sacrificing the water pressure we all love. That WaterSense label means that the shower head performs at least as well as a standard model, while also being 20 percent more water efficient. It’s a satisfying project for a weekend afternoon, and you can save LOTS of water!

 

10. Use a shower bucket and put that cold water to work.

There’s no getting around it – your shower takes some time to warm up. So keep a bucket in the shower and fill it while the shower warms up. Once the water is warm enough, set the bucket aside, enjoy your shower, and afterward you can use that cold water for your plants or humidifier.

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