Environment

Here’s a newsflash, Louisville: there’s been a lot of rain lately. In the past month, the National Weather Service has measured nearly six inches of precipitation. We’re two weeks into July, and it’s already close to being one of the 10 wettest Julys the city has ever had.

That is why it’s important to conserve water.

In America, conversations about water conservation tend to focus on the opposite problem: drought. But in Louisville, abundant rainfall can be a serious issue. Besides of obvious issues like the threat of the Ohio River flooding, the way Louisville’s sewer system was designed years ago means the system is easily overwhelmed during heavy rain. To help ease its burden, here are four things you can do when it’s wet outside to keep excess water out of the sewers.

1.    Don’t water your lawn. This one is obvious. But some homes and businesses have sprinklers that turn on at the same time every day. Put this on hold until your grass legitimately needs water.
2.    Don’t do laundry. According to the EPA, the average washing machine uses 41 gallons of water per load. High efficiency machines use about half of that, which is still a significant amount of water.
3.    Think before you flush. Maybe consider the old suggestion “if it’s yellow, let it mellow; if it’s brown, flush it down.” Within reason, of course.
4.    Don’t drain your pool. At least not just for the heck of it.

Here’s why these steps are helpful.

Inside the Watterson Expressway, Louisville has a combined sewer system. That means that everything goes into the same pipes: wastewater from the city’s toilets and sinks mixes with the rainwater that runs into sewer grates. Under normal conditions, all of that water ends up at the sewer treatment plant.

But when there are heavy rainfalls, there’s too much water for the treatment plants to handle. The city’s sewers are full of water running out of drainpipes and off streets, and Louisville’s Metropolitan Sewer District has permission to release it straight into the Ohio River without treatment. MSD is currently under an EPA consent decree to reduce the number of sewer overflows, but right now, that’s still the way things work.

Here’s how MSD illustrates the differences between dry weather and wet weather:

cso_ssoLouisville MSD

To make matters more complicated, these sewer overflows can also cause flooding for homes in low-lying areas. If the Ohio River and other tributaries rise, there’s a possibility that the pipe the system uses to release sewer overflows could be underwater. That causes backups around the system, and water goes back into basements and up through drains.

So while the ground is saturated and all of the excess wastewater is running straight into rivers and creeks, think about how you’re using water.

Erica Peterson is WFPL's Director of News and Programming.