What Is Gray Water — and How Can Using It Help Save You Money?

The average American family uses an average of 300 gallons of water every day — and 75% of it goes down the drain. Some of it isn't anything you'd want to reuse around the house (think toilet water), but some can be easily collected and reused. Here's what it is, where to get it, and what you can use it to do.

Any time you shower, boil water, or run your washing machine, you're generating gray water. This isn't the stuff that goes down your toilet, and it's possibly not the stuff that goes down your kitchen sink, as that might have some grease in it. But the rest of the water in your house fits the bill.

The distinction between black water and gray water is pretty clear — any water with poop or the possibility of poop in it is black water. That stuff you can send down the drain without a second glance.

Collecting gray water can be a challenge or shockingly easy. In the laundry room, your washing machine has a built-in pump to put your gray water down the drain. You'll need a diverter valve to collect gray laundry water. Also remember that if you're washing reusable diapers or any laundry with less-than-savory stains, that's black water — not gray. Finally, if you're collecting laundry water, make sure you use detergent that's biodegradable and plant-friendly.

If it's shower gray water you're after, you can put a bucket by your feet when you bathe, or put the stopper in the drain for collection after (this will work for people who bathe in a tub rather than a shower, too). In the kitchen, use a smaller bucket in the sink, employ the stopper method, or place a bowl under the colander when you drain things like pasta. Voila, gray water collected.

Dump it on plants indoors or out, or use it in your toilet so you don't have to waste potable water on your next visit. If you're going to keep your lawn instead of adopting a water-wise landscape, you'll save plenty of money using gray water for irrigation.

Most states have rules about using and collecting gray water, but good news: some states offer tax credits for using it, too. If you have a Homeowners Association where you live, it might have rules, too.

Actually, no. Because it's not clean water, the material in it can attract germs and bacteria. But that doesn't mean you can't use it — just use it as soon as you collect it.