Around the Water Cooler: Leaving the Outhouse Behind

By Lahne Mattas-Curry

Stormwater flows from a large pipe.

Green infrastructure helps keep stormwater in place.

This week, and every Thursday that follows, I’ll introduce you to the EPA scientists and engineers who work to make sure our water stays clean and that we have enough for generations to come.

Today I’m kicking off a series on green infrastructure while we recognize the role of science and innovation in the Clean Water Act, which turns 40 this year.

What is green infrastructure? It’s actually just a fancy term for rain gardens, rain barrels and cisterns that keep excess water out of our storm drains.

But let’s start with some history. In the mid-1800s, flush toilets came to America. Everyone wanted one so that no one would have to make that nightly cold, dark trek to the outhouse. Soon, though, it became obvious that when you “flush” the toilet inside the nice warm house, the waste has to go somewhere. Initially that somewhere was our streets.

Thankfully, that did not last long.

Motivated by smelly city streets, municipalities added underground pipes to carry the wastewater from homes and businesses and deposit in waterways where it could be diluted and carried away in the current. The pipes, though, also carry stormwater that rushes off the streets during heavy rain.

Welcome to the combined sewer system.

There are approximately 800 cities and towns across America that still use combined sewer systems, including big ones such as New York and Chicago, and smaller ones like Omaha and Louisville.

Today, these systems don’t feed directly into our waterways. The water is first sent to a treatment plant where it is cleaned.

The problem with these combined sewer systems is that when it rains hard, the polluted wastewater doesn’t always make it to the treatment facility, and instead goes directly to our rivers, streams and other waterways. (A violation of the Clean Water Act. And also pretty gross.)

But changing out all these networks of pipes—called gray infrastructure—is costly. EPA scientists and engineers have been working with several municipalities around the country to find alternatives—innovative solutions to efficiently and inexpensively reduce runoff flowing into combined sewer systems.

Each Thursday over the next few weeks I’ll highlight green infrastructure research and best practices while sharing ways you can make a difference in your community.

In the meantime, check out this interactive tool from the Arbor Day Foundation to compare the difference between a community with increased green infrastructure in the form of more trees versus a community with less. Which would you rather live in?

About the Author: Lahne Mattas-Curry works with  EPA’s Safe and Sustainable Water Resources team, drinks a lot of water and  communicates water research to anyone who will listen.

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