Last Updated on April 14, 2023 by Mattias
This guide will teach you about rainwater harvesting and how it works.
As you’ll discover below, harvesting gallons of rainwater isn’t so hard.
So let’s dive in, so you can become an RWH geek just like us!
What Is Rainwater Harvesting, and how does it work?
Rainwater harvesting (RWH) is when you collect and store rain instead of letting the rain runoff. Harvesting rainwater has been done by our ancestors for thousands of thousands of years, and still to this day, it remains.
Lately, it’s becoming more common for property owners in the united states to harvest rainwater, which is something we love!
Mostly the rainwater is harvested from the roof like this:
First step: Rain pours down on the catchment surface and collects in your rain gutters
Second step: The water flows into the gutter downspout
Third step: The water goes into your rainwater storage tank.
The collection container can be a water tank or a simple rain barrel. There are many rwh systems to choose between, but a big tank is a great way to store water.
Some tanks can be underground, while others only can be on the surface.
Imagine the amount of water they can harvest and how much money they can save in one year. But it’s good to know that the water quality must be good if the water is for human consumption.
What Are The Benefits Of Rainwater Collection?
There are many benefits to harvesting rainwater. But the biggest one for us is that it doesn’t have to be hard. Keep it simple if you can’t afford a big rainwater harvesting system. The important thing is to start!
- Free water for everyone to harvest
- Reduced cost on your water bills
- Decreases your demand for water
- You don’t need to import water
- Gives the groundwater better quality and quantity
- Control over your water supply (essential for those cities that have water restrictions)
- Rainwater doesn’t contain heavy metals, which makes it a much better water source for gardens and landscape plants.
- You can use easy techniques and technologies that don’t cost much.
- It can be used for backup in case your well dries or emergency.
- Protects your local watershed
- It can be used for basic uses like flush toilets or a washing machine.
- It can be used as potable water (filtering is needed)
- It can be used for outdoor water use like landscape irrigation or a vegetable garden.
But, it doesn’t end there. Rainwater harvesting has environmental benefits, which is something we all should be aware of.
Environmental benefits of Rainwater Harvesting
Collecting rainwater is great for the environment; here’s why:
Reduce the draw on stressed systems (conserving water)
Sometimes the groundwater level and reservoirs overflown. When rain harvesting the water from your roof, you can help these systems from becoming too full. (urban flooding)
Restore the water cycle (Hydrolic cycle)
If you reduce the stormwater impacts, you’ll recharge the groundwater.
Almost 50% of stormwater goes down into the ground, where it hydrates the soils and recharges the groundwater. Approximately 40% evaporates, and 10% runs off.
Developed Landscape (for example, your neighborhood) – Here, 15% infiltrates and 55% runs off. Why, you may wonder? Because the water can’t penetrate hard surfaces like rooftops, parking lots, roads, and so on…
When you harvest your rainwater for use in your garden, you can reduce the impacts of stormwater by harvesting the water on-site instead of letting it run off.
When you use it later, the water goes back into the ground. Then the soil gets hydrated, all the plants get nourished, and our groundwater is recharged.
After this process, you did something awesome…you restored the last puzzle piece in the hydrolic cycle.
Protect your local Watershed by reducing erosion & pollution
When the rainwater hits the ground (on-site), it’s filtered by the earth.
It’s stopped from joining storm drains and surface waters as polluted runoff.
Did you know that when the stormwater runs heavy, it makes stream banks erode? This can cause devastating damage to wildlife and waterways.
The biggest source of pollution in the USA is stormwater runoff. So if you slow it down, spread it in your garden or collect the rainwater on your site…you can prevent this scenario from happening.
Reduced Carbon Footprint
By reducing energy use, you can mitigate climate change.
There’s a strong connection between water and energy in our world. You can contribute to a collective energy saving by reducing your dependence on pumped water.
Make your garden happy and healthy
Plants love rainwater, and it’s no coincidence. Direct rainwater is the best clean water source we got.
Nature has designed rainwater with a perfect pH balance of 5.0 – 5.5. It also contains good nitrate levels. Which is ideal for rain gardens.
Why Is Rainwater Harvesting Important?
Rainwater harvesting is important because the climate is changing rapidly with extreme temperature changes. So it’s important we take care of our natural resources.
One day you can sit on your porch with a glass of coke and enjoy the weather, and the other day the rain pours down. We will probably see more dry periods in the future.
During these dry periods, it will be essential to have your rainwater collection system, so you can harvest every inch of rain during the “rainy” periods.
It’s about taking control and ensuring that you, your family, and your friends can have enough water for your water needs.
It’s also good for your wallet. The water bill cost can vary depending on where you live. But just look at your water bill and follow the formula: water bill cost x 12 = total cost over one year.
Now think about what you can do with that money instead if you harvest your water.
Rainwater Harvesting Methods and Techniques
Rooftop rainwater harvesting and surface runoff are the two main methods.
Whatever method you choose is up to you, but when you see all the harvested water, you will start to notice one thing: It’s fun!
The feeling of being independent on the water is amazing. But perhaps you’re wondering what method is the best for rain harvesting? Or which method is the cheapest one?
Let’s go through the most common methods.
Using a barrel for collecting rainwater is without a doubt the easiest and one of the cheapest ways.
It’s even possible to collect rainwater without gutters. .
You must connect your gutter system to your barrel or let it stand underneath the downspout to catch all the rain pouring down the gutters. However, they may overflow quickly since their capacity is quite low, so you can’t fill them with so much water.
A dry system is a variation of a rain barrel, except it involves a bigger storage volume. This method is good for you if you live in an area with many thunderstorms. The maintenance isn’t so hard and is a pretty cost-effective method.
One negative thing is that the tank must be placed next to your house and it’s not so good looking. But if that doesn’t bother you, go for it.
A wet system is when you connect all the pipes underground and lead the water to an underground tank. This means you don’t need the tank next to your house and can provide a much bigger area to store rainwater.
This is an expensive investment, but still a good one.
Many rainwater catchment systems depend on how much you want to harvest.
What is rooftop rainwater harvesting?
Rooftop rainwater harvesting is a technique in which rainwater is caught by the roof catchments and then stored in reservoirs.
Which method is best for rainwater harvesting?
“Rain barrels are the best when harvesting rainwater!” That is what many people would say. But we always preach this: It’s about your goals. Is it for outdoor purposes? Or do you want to become free from the public water supply system?
Because if you want that, that demands a big tank, that can collect all the amount of rainwater that you would need.
Summary Collecting and Harvesting Rainwater
I hope you enjoyed this guide on harvesting rainwater.
As you discovered, harvesting rainwater has many benefits, and it will probably become even more popular in the future. Just make sure you know the laws for harvesting rainwater before you start doing it. The storage of rainwater will become essential for home use and water consumption. But before you start drinking your rainwater, make sure to read our guide about drinking rainwater.
Meet Mattias Jonsson, the head of content at RainSaucers. Passionate about gardening and water-related topics, he’s dedicated to providing expert information and resources to help improve your home, health, and wallet. Learn from his research and experience.