Skip to Content

Is It Illegal to Collect Rainwater?

Is It Illegal to Collect Rainwater?

Is it illegal to collect rainwater? Homeowners with rainwater harvesting systems can save up to 40% on their water bills, according to some sources, but some people believe that it’s illegal to collect rainwater in the United States.


In this article, we’ll answer the question about whether it’s illegal to collect rainwater. We’ll also explore some resources and programs that can help you, if you decide that you want to attempt it.

Is it illegal to collect rainwater?

There are no federal laws that would make it illegal to collect rainwater in the United States. This is an issue that is left up to states, but in fact, many states actively encourage you to harvest rainwater.

According to the Department of Energy, it is legal to collect rainwater in all 50 states although some states may have rules about how the water is collected, how much you can collect, and how you can use it. As long as you are following the rules, then you’re allowed to collect rainwater!

Each state handles it differently.

According to the Department of Energy’s Rainwater Harvesting Regulations Map, states generally fall into one of six categories. These categories determine how the state regards rainwater collection in their laws.


The Department of Energy organizes states based on these categories:

  • Very Limited
  • Not Illegal / No Regulations
  • No Regulations / Encouraged
  • State Regulations
  • State Regulations / Encouraged
  • State Regulations / Incentives

However, to simplify matters for this article, I have decided to combine similar categories so that we have just three categories for you: Regulated, Not Regulated, and Restricted.


In many states, those who wish to collect rainwater have to follow strict government regulations about how, when, and where the water is collected. Sometimes, there are even restrictions regarding how much water can be collected or how that water can be used.

The states that regulate water collection include:

The areas that offer incentives include:

  • Arizona
  • Arkansas
  • California
  • Georgia
  • Idaho
  • Illinois
  • Minnesota
  • New Mexico
  • North Carolina
  • Ohio
  • Oklahoma
  • Oregon
  • Texas
  • Vermont
  • Virginia
  • Washington
  • Washington DC

The degree of regulation varies wildly between states. For example, rainwater collection is allowed in Idaho and that right was reaffirmed in a clarification letter from the Office of the Attorney General. However, the Arkansas Board of Health requires that rainwater only be used for non-potable purposes and every rainwater collection system must be designed by a professional engineer.

Some of the states in this list encourage rainwater collection by offering incentives to residents and businesses who choose to do it. However, these incentives vary by state. For example, Arizona allows cities and towns to provide financial assistance to help you fund rainwater harvesting systems but Washington only provides a 10% stormwater management fee reduction for businesses who use rainwater systems. In California, the incentives are set at the county level.


To find out what the incentives are in your area, you’ll need to contact your state’s Department of Water Resources. Some states have a Department of Energy that is in charge of water instead.

Not Regulated

According to the Department of Energy, most states have no laws regarding rainwater collection at all. These states include:

  • Alabama
  • Alaska
  • Connecticut
  • Delaware
  • Florida
  • Hawaii
  • Indiana
  • Iowa
  • Kansas
  • Kentucky
  • Louisiana
  • Maine
  • Maryland
  • Massachusetts
  • Michigan
  • Mississippi
  • Missouri
  • Montana
  • Nebraska
  • New Hampshire
  • New Jersey
  • New York
  • North Dakota
  • Pennsylvania
  • Rhode Island
  • South Carolina
  • South Dakota
  • Tennessee
  • West Virginia
  • Wisconsin
  • Wyoming

It is important to note that although these states do not have any statewide regulations, there may be county or municipality-level ordinances that regulate the collection of rainwater.


Unfortunately, there are a few states that restrict the collection of rainwater. These states are Nevada and Colorado.

In Colorado, HB-1005 allows most residents to collect up to 110 gallons of rainwater from rooftops as long as the roof does not cover more than four housing units. The water can only be used for outdoor purposes. Residents with a well can collect an unlimited amount of rainwater on their roofs for indoor and outdoor uses. However, all other rainwater harvesting methods are illegal under Colorado law.

In Nevada, the law clarifies that residents can only collect rainwater from single-family roofs and the water can only be used for non-potable domestic uses. This could include things like gardening, irrigation or washing cars. The water cannot be used for drinking, cooking or personal hygiene.


Pros & Cons to Collecting Rainwater

Collecting rainwater is a great way to cut down on your water bill. After all, you can use the collected water for gardening, irrigation, washing cars or pets, flushing toilets, cleaning, firefighting and so much more.

We all know that water is a very useful resource but some people have claimed that it is illegal to collect rainwater. Although we aren’t sure where those rumors started, we decided it was time to fact-check these claims and set the record straight.

Some benefits to collecting rainwater include:

  • Water Conservation: Collecting rainwater reduces demand on municipal water supplies, which is particularly beneficial in areas facing water scarcity.
  • Reduced Water Bills: Over time, rainwater collection can help in reducing water bills, providing financial relief to households.
  • Sustainability: Using collected rainwater for non-potable uses is an environmentally friendly practice that contributes to sustainability.
  • Water Quality: Rainwater is generally soft water, which is better for plants and can reduce the amount of detergents needed for washing.
  • Reduced Soil Erosion and Runoff: Rainwater collection can help in reducing soil erosion in your yard and can limit the runoff that might pollute local waterways.
  • Emergency Preparedness: Having a reserve of rainwater can be invaluable in cases of water supply interruptions due to natural disasters or other emergencies.

Of course, this decision is not without drawbacks. There are some negative impacts that you need to be aware of before you make a decision.

  • Initial Cost: The setup cost for a rainwater collection system can be high, although there may be government incentives to offset this.
  • Maintenance: Filtration systems need to be regularly maintained and cleaned to ensure water quality, which can be time-consuming.
  • Water Treatment: If you plan to use the rainwater for potable purposes, it needs to be properly treated which involves additional costs and equipment.
  • Climate and Seasonal Dependency: In areas with little rainfall or in seasons when rain is scarce, the benefits of a rainwater collection system may be limited.
  • Legal Restrictions: Some areas have restrictions on the collection of rainwater, so it’s essential to check local regulations before installing a system.
  • Space: Large collection tanks can take up valuable space in your yard or property.

How to Collect Rainwater

Getting started with rainwater collection may seem daunting, but breaking it down into manageable steps makes the process more approachable.

The first essential step is to check the legal aspects of rainwater harvesting in your area. Although this article outlines the general rules for your state, it’s always important to check with your local governments to see if they have specific regulations. You’ll need to comply with these to avoid any legal complications. It’s important to research whether you need any permits, and what the restrictions on water usage might be.

The second step involves planning, which starts with defining the purpose of your rainwater collection system. Are you looking to simply water your garden, or do you want to use it for more complex domestic tasks like flushing toilets or even for drinking water? The purpose will influence the components you’ll need. For instance, if you plan to use rainwater for drinking or cooking, a more rigorous filtration and treatment system will be necessary to ensure water quality.

Once you’ve determined the purpose and legalities, you’ll need to consider your budget and system sizing. Calculating how much rainwater you could potentially collect and how much you’ll need for your intended usage helps you decide on the size of the tank and other components. Costs can vary widely depending on the complexity of the system. Some governments also offer rebates or subsidies for rainwater collection systems, which could help offset the initial setup costs.

The fourth step is installation. Depending on your level of expertise and the complexity of the system, you can either opt for a DIY installation or hire professionals. Either way, you’ll need to consider where to place the tank, how to channel the water from the roof to the tank, and how to integrate it into your existing plumbing system if necessary. Make sure the storage tank is in a location that’s both practical for water collection and convenient for water usage.

Lastly, but equally important, is maintenance. Once your system is up and running, it will require regular upkeep to ensure that it functions efficiently and that the water remains clean. This involves checking for leaks, cleaning the gutters, emptying and cleaning the first-flush system, and periodically cleaning the tank. If you’ve opted for a more complex system that includes filters or UV sterilization, those elements will also need regular checks and replacements. All these steps, when taken together, will help you create a rainwater collection system that is both efficient and safe to use.

How to Get Financial Help

If you decide that you want to establish a system to collect rainwater, you may be able to get financial assistance and other support from various government and nonprofit resources.

Utility Companies

First, check with your utility company to see if they offer any incentives, rebates, or programs that can help. After all, many water utilities have special programs available to encourage water-saving measures.

You will need to contact your water company to see if they have any resources available. If you have a private well, just skip to the next step.

Government Programs

Next, ask your local governments about it. Contact officials at the state, county and city level so that you don’t miss any amazing opportunities!

Some areas offer discounts or even sell the items you’ll need directly. For example, the city of Seattle sells rain barrels directly to citizens through the Seattle Conservation Corps. They even sell food-grade Rain Tanks that can old more than 500 gallons of rain water!

Other areas may offer rebates. The amount of the rebate that you can receive will vary depending on your local program.

In Tucson, Arizona, residents who take a free greywater harvesting class can get up to $2,000 in rebates on a rainwater harvesting system or up to $1,000 on a greywater harvesting system!

Residents of Austin, Texas, can get up to $5,000 to install a system that collects rainwater.

Nonprofits & NGOs

Next, look at environmentally-conscious nonprofits in your area. Nonprofits and organizations focused on sustainability and environmental conservation often have extensive networks and resources that can be incredibly helpful for your rainwater harvesting project.

These organizations frequently collaborate with government agencies, educational institutions, and even corporate partners to promote water conservation and other sustainable practices.

By connecting with them, you may gain access to a wealth of information about grants you may not have discovered otherwise. They might also offer workshops, seminars, or webinars on how to set up and maintain a rainwater harvesting system, often featuring experts in the field.

Educational Institutions

Finally, educational institutions like colleges and universities often have resources for rainwater harvesting. They may be able to help you with funding or the expertise to set up your rainwater collection system.

Sometimes, connecting with a student or professor at a local college can make all the difference! Networking with academics, researchers and students may help you connect with other resources that we aren’t currently aware of.


It is not illegal to collect rainwater in the United States, although some areas require you to follow strict regulations in order to collect it legally. You need to be aware of the regulations at every level of government in your area. If you are interested in collecting rainwater, this article also provides insight into how you can get financial assistance to set up your system.