Why Are Pipes Bursting in Texas?

Water is important for a lot of reasons: it makes up most of human beings, it covers most of the surface of planet Earth, and it’s refreshing on a hot day.

It’s also special because, unlike most things, it is most dense as a liquid.

Density is a measure of how tightly packed something’s molecules are. If they’re really tightly packed, there’s a lot of mass in a small space, and it’s really dense. If they’re really spread out, they’re not very dense, because the molecules are spread out over a larger space.

Both of these substances have the same amount of stuff, but the first one has the stuff squished into a smaller space. We say it is more dense.

For most things, when they are cooled down enough to turn into a solid, their molecules pack together tightly and become more dense than when the thing was liquid.

Water is different. Water as a solid (ice) is less dense than water as a liquid. This turns out to be very, very important to us. It means every winter, when bodies of water freeze over, the less dense ice floats on top, keeping the liquid water cozy and warm underneath. This helps keep everything underneath the ice alive through the winter, which is incredibly helpful for keeping life…alive. In the millions of years of life on Earth, if life had to start from scratch after every spring thaw, there’s no way we could’ve evolved such complex organisms as humans.

That’s great, until it comes to pipes. When pipes are full of water that’s not doing much, and they get too cold, the water will freeze. Ice is less dense than water, which means the molecules are more spread out, which means they take up more space. If the pipe was full of water in the first place, and suddenly it’s full of ice that takes up more space, ka-BOOM! The pipe bursts.

In many places in the US, the pipes are built within the house, so they stay as warm as the house does. As long as the pipes never get below freezing, they won’t burst. However, in regions of the US that are usually warm (like Texas), they build pipes outside the heated area of the house (why waste space inside the house if you don’t have to?). On the rare occasion the weather gets very, very cold, those pipes are in big trouble.

The scary part? As the global climate continues to change, erratic weather like this will become more and more common.

Stay warm and conserve energy, please.