What Is Rainwater Harvesting? 12 Things (2023) You Must Know

Rainwater harvesting — the collection and storage of rain to use as a primary water supply — is one of the simplest and oldest methods of self-water supply.

And it’s still a great one.

Rainwater is the cleanest form of water on the planet.

While you’ll still need to filter it before use, learning how to harvest rainwater has numerous benefits.

In this blog, we’ll tell you everything you need to know about this cheap and sustainable system.

Let’s get started.

1. What is rainwater harvesting (RWH)?

Rainwater harvesting is the collection and storage of rain for use.

RWH often involves harvesting rain from a roof.

As the water is channeled into downspouts, it can be directly transferred into rain barrels or other collection containers.

Rainwater harvesting is a viable alternative for anyone looking to supply their household or business with water.

While it’s traditionally thought of as something that homesteaders do, anyone can use these methods and reap the rewards.

You may also hear it referred to as rainwater collection, rainwater catchment, roof water collection, or rooftop water collection.

RWH is a viable technology in both urban, suburban, and rural settings.

It provides you with the ability to take advantage of a free water source and can be configured to supply your entire house or landscaping needs.

2. Is rainwater clean?

If you’ve never harvested rainwater previously, you may worry if it’s clean.

Is it safe to drink?

Will it make me sick?

The answer all depends on where it’s coming from.

In general, most rainwater is safe as long as you don’t drink it near chemical plants and areas of high pollution.

However, the general recommendation is that you filter it before you drink.

Another way to make the rainwater safer is to boil it to make sure you’re killing off any pollen or bacteria that may be lingering in the water.

Boiling it is a good step if you want to use it for non-consumption purposes, but we still recommend going the extra step of filtration to ensure you have clean water.

3. Is rainwater harvesting legal?

As you begin your research, you may hear some horror stories about people facing legal consequences for harvesting rainwater.

This will leave you with the question: Is it legal?

Yes, it is legal.

There are no federal laws that restrict rainwater harvesting, and while some states have strict regulations, most states will allow their residents to collect rainwater freely.

4. What types of regulations and restrictions do states have?

Some states have regulations about the amount of rainwater one can collect as well as how you can collect it.

That said, most states allow their citizens to collect rainwater freely and even encourage its collection.

The states with regulations believe that the collection of rainwater may halt the rainfall’s natural flow into the Earth’s aquifers and streams.

Thus, it will disrupt the hydrologic cycle.

However, a study published in the Scientific World Journal states that the amount of rainwater collected by individual homes would have little to no impact on the overall hydrological cycle.

As most of the collected rainwater would be used for gardening and household purposes, the water would eventually be returned to the ground.

And then sometimes states also restrict rainwater usage because of old prior appropriation laws.

Today, most states have shifted their laws in favor of private RWH.

Utah and Colorado are the only states with heavy regulation, and Colorado is the strictest of the two.

In 2016, they passed a bill that allows for the collection of rainwater with a 110-gallon maximum capacity.

See the next section for more information about the restrictions and regulations in each state.

So, remember, rainwater is a resource.

Once it falls on your property, it’s generally yours to use without restriction.

Organizations like the American Rainwater Catchment Systems Association (ARCSA) are generally working with government organizations to advocate for rain harvesters all over the country.

5. What is a state-by-state guide to rainwater harvesting?

Are you still worried about the possible restrictions in your state?

If so, we put together a state-by-state guide to help you understand any restrictions or regulations in your local area.

bulletAlabama – No regulations or laws against rainwater harvesting

bulletAlaska – No regulations or laws against rainwater harvesting

bulletArizona – Regulated through the Department of Water Resources; city or town may provide money to fund rainwater harvesting systems

bulletArkansas – Regulated through the State Board of Health, which allows a system used for nonpotable water that complies with the Arkansas Plumbing Code and is designed by a professional engineer

bulletCalifornia – Regulated through the Division of Water Rights, which includes specific system requirements and licensing criteria that landscapers must follow to install rainwater harvesting systems

bulletColorado – Each house is allowed a rain barrel of up to 110 gallons for storing rainwater

bulletConnecticut – No regulations or laws against rainwater harvesting

bulletDelaware – No regulations or laws against rainwater harvesting

bulletFlorida – No regulations or laws against rainwater harvesting

bulletGeorgia – The Department of Natural Resources, Environmental Protection Division regulates water resources; state plumbing code allows rainwater harvesting for outdoor use

bulletHawaii – No regulations or laws against rainwater harvesting

bulletIdaho – Legal to capture rainwater off roof structures and the ground if the rain has not entered a natural waterway

bulletIllinois – Local government can regulate rainwater harvesting per state plumbing law; rainwater can only be used for nonpotable uses

bulletIndiana – No regulations or laws against rainwater harvesting

bulletIowa – No regulations or laws against rainwater harvesting

bulletKansas – No regulations or laws against rainwater harvesting

bulletKentucky – No regulations or laws against rainwater harvesting

bulletLouisiana – No regulations or laws against rainwater harvesting

bulletMaine – No regulations or laws against rainwater harvesting

bulletMaryland – No regulations or laws against rainwater harvesting

bulletMassachusetts – No regulations or laws against rainwater harvesting

bulletMichigan – No regulations or laws against rainwater harvesting

bulletMinnesota – Regulated through the Minnesota Plumbing Board, which requires permitting and code compliance

bulletMississippi – No regulations or laws against rainwater harvesting

bulletMissouri – No regulations or laws against rainwater harvesting

bulletMontana – No regulations or laws against rainwater harvesting

bulletNebraska – No regulations or laws against rainwater harvesting

bulletNevada – Residents are allowed to collect rainwater off of a single-family roof for non-potable domestic use

bulletNew Hampshire – No regulations or laws against rainwater harvesting

bulletNew Jersey – No regulations or laws against rainwater harvesting

bulletNew Mexico – Regulated through the State Engineer Office; no specific requirements exist for outdoor uses; indoor uses must meet water quality standards

bulletNew York – No regulations or laws against rainwater harvesting

bulletNorth Carolina – Rainwater harvesting is encouraged due to water conservation efforts

bulletNorth Dakota – No regulations or laws against rainwater harvesting

bulletOhio – Rainwater harvesting is legal, but there are codes and regulations that must be followed

bulletOklahoma – Encouraged through state legislation: Water for 2060 Act

bulletOregon – Rainwater harvesting is legal, but only using rooftop surface water

bulletPennsylvania – No regulations or laws against rainwater harvesting

bulletRhode Island – No regulations or laws against rainwater harvesting

bulletSouth Carolina – No regulations or laws against rainwater harvesting

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