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It is easy to set up a basic rainwater system with even just a few rain barrels. But, what are you going to do with that rainwater? Beyond the most obvious: watering the garden, do you know what else you can do with collected rainwater?

What Can Collected Rainwater Be Used For?  Rainwater can be used for everything in your home from laundry to flushing the toilet and even filling up your swimming pool! 

Read on to learn about unique uses of rainwater, some of which you probably haven’t thought of. If you aren’t collecting rainwater already – what are you waiting for? Read this post to learn how to get started and conserve and reuse one of nature’s greatest free resources- rain!


Related: In order to USE your rainwater, you need a way to MOVE your rainwater. My favorite way to do this is with a flojet pump. While this pump is not the cheapest, you wonʻt have to replace it after 2 weeks.

Flojet Quiet Quad II


12 Ways To Use Rainwater

1. Bathing/showering

No, you don’t need to heat water on the stove and take bucket showers! You can set up your home’s plumbing to pump water from your rainwater reserve tank or other rainwater storage system using a small on demand pump you can buy on Amazon.

What’s more – rainwater is actually better for your skin and hair than the highly-chemically treated water you get from metered water. If you have hard water, switch it up for rainwater and see the difference in just a week or two.

Before moving on, you might want to check out how to install a pump to work with a rain tank if you havenʻt done so already. It makes using your harvested rainwater so much easier!

2. Laundry

Change the ‘in flow’ of water to your washing machine to come from your rainwater storage.

Want to do even more? Save the ‘outflow’ or greywater from your laundry rinse water to use in the garden. Learn more about reusing laundry water in your garden in this post.

3. Flushing the Toilet

If you have a rainwater storage system, connect your toilet to the system and your toilet will automatically refill after every flush with glorious, free rainwater.

If you don’t have a system, but you collect rainwater in barrels, go basic: keep a bucket of rainwater in your bathroom and manually flush it with the rainwater. There is no wrong way to reuse rainwater in your toilet, it really can be basic and easy.

4. Washing your vehicle

Motorcycles, jet skis, bikes, or cars — all types of vehicles can be washed with rainwater. 

Actually, because rainwater does not have added chemicals in it, it is better for your vehicle and car-safe detergents lather up better with rainwater than with tap water! So, you can clean your car or bike to a sparkling finish with less harsh scrubbing.

5. Drinking

Yes, you can drink rainwater! Of course, you have to filter it and treat it first, but then it is safe for drinking. 

Some methods for making rainwater safe to drink are UV light treatment, chlorination, charcoal filtration or, the most basic: filtration and then boiling for 5 minutes. 

You can learn all about 3 ways to turn your rainwater into drinking water in this post. It will tell you everything you need to know about how to make rainwater drinkable.

6. Home cleaning/mopping

I don’t love mopping the floor, but if I have to do it, I feel happier about this chore when I use rainwater.

7. In the swimming pool

There are a few recommendations around using rainwater in your swimming pool. 

Untreated rainwater is very inviting for insects and bacteria, which would love to live in your swimming pool. To prevent against this there are several steps you should take to safely use rainwater in your swimming pool:

  • Introduce a first-flush system, ensuring that the initial water from your roof is not used in your pool
  • Use treated water from your rainwater storage tanks, not directly off the roof (even when using first-flush)
  • Pass the rainwater through your pool’s balance tank as it enters your pool. Do not put it directly into your pool from the rainwater storage tank.
  • Chlorinate the water according to your pool manufactures’ directions, this should prevent bacteria from growing and insects from laying eggs in your pool water

8. Fish ponds

Your fish will love this fresh water! But, you may need to check regularly for algae growth, as rainwater is so pure it’s easy for things (even things you don’t want) to grow in it.

I have fish in a pond fed by rainwater and they are thriving.  A few water plants, the right mix of fish species and you have yourself a low maintenance water garden.

9. Fire suppression


I knew someone in the fire prone region of Malibu that would fill his pool with filtered and treated rainwater.  In case of fire, he had a gas powered pump that hooked up to fire hoses that he could use in the event of a brush fire.

In fact, he had to do just that in 2017 and ended up saving his home because he was prepared with the proper firefighting equipment an 10ʻs of thousands of gallons of rainwater that he harvested.

You can also set-up your home’s sprinklers to use rainwater. Several locations in the continental USA have tried, tested and approved rainwater as an appropriate source for sprinkler systems, even for storing water in fire engines.

Some locations have building codes requiring the water be at a certain elevation and not require a pump to operate, so find out what the regulations are in your area before setting up your fire suppression system to work with rainwater.

10. Drought-proofing your home

This one is especially important if you live in a zone that regularly experiences droughts (Texas, California, I’m looking at you).

Since you can expect the dry weather to come, at least prepare for it! When months go by without a drop of rain, you will be so glad that you saved the rainwater!


Even the most drought-ridden areas do get some rain. While you certainly want your garden to get that refreshing rain, your roof doesn’t need the moisture, your garage doesn’t need the moisture.

Make small changes to ensure even this little bit of rain hitting the roofs of your buildings is collected and stored so you can use it in the future.  

11. Rehydrating aquifers

The ugly truth is that groundwater is not an endless resource, and in many locations, it is being depleted at a faster rate than it is being replenished. 

You can take steps to rehydrate aquifers through check dams, on-contour swales, ponds and other water harvesting earthworks. Getting this water back into the earth will have positive benefits for years into the future.

12. Reduce strain on rivers and lakes.

You may already know this, but much of our potable water (water safe for drinking or other domestic use) comes from rivers and lakes – open sources of water.

It is intensely filtered and purified to become safe to drink. Do you really think lake water is cleaner than rain water? It certainly is not! 

Another problem is that in drought prone areas, these lakes and rivers are running dry.  Doesnʻt it make sense to have a backup supply of one of THE most important resources on the planet?

While the city water continues to be extracted from these water sources, you can make a difference and harvest rainwater to lessen the burden. See above; you can make rainwater safe for drinking, too!

Two Ways To Harvest Rainwater: Passive and Active

Active Rainwater Harvesting is what most people think of when they hear ‘rainwater harvesting’ – collecting and storing water in reserves, tanks, etc. This harvested water is used for domestic purposes or irrigating a home garden. This active approach is important for daily life and for reducing use of other sources of water.

To learn more about how to set up your own water harvesting system, check out this post that covers the ins and outs of how to do just that.

Passive Rainwater Harvesting, on the other hand, is probably more important than active harvesting, ecologically-speaking. Passive Harvesting helps the greater environment in the long-term, building up underground springs, refilling aquifers and other natural sources of water. 

However, passive rainwater harvesting is more difficult to see, because so much of it happens underground or within existing ponds. But, over time, these efforts will make a huge difference for groundwater – and for the next generation.

The moral here is that even in drought-affected zones in America, there is some rainfall. If you take measures to collect rain and use it effectively, you can conserve water in any number of areas: the kitchen, the bathroom, the garden and more. These changes can make a difference in both the short term and long-term, in regards to water conservation.

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