Is it Illegal to Collect Rainwater: 2023 Complete State Guide

Why do some states require permits?

Because the topography of the entire United States varies greatly in terms of water availability, each state will follow different doctrines on how water should be used amongst its residents. Eastern states, where water is generally more abundant, have different water laws than the drought-heavy Western states.

Water laws are meant to find a balance between protecting the rights of individuals to have access to water sources and protecting these water sources from being unfairly used or polluted.

While water laws vary greatly between states due to the varying differences in water availability, most states generally follow a law doctrine known as "reasonable use." The reasonable use doctrine states that anyone who has a right to the water can reasonably use it for their own benefit as long as it doesn't restrict the rights of others to use it as well.

The hydrologic cycle

As rainfall seeps into the earth's crust, it replenishes the ground with water as part of the earth's natural hydrologic cycle. Excessive amounts of rainwater catchment may disrupt the natural flow of runoff water that would otherwise find its way back to the soil.

While a study published by the Scientific World Journal shows that the amount of rainwater that could potentially be collected by individual homes would have little to no effect on the hydrologic cycle on a macro-level, a handful of states limit the volume of collectible water to a certain number of gallons.

Prior appropriation laws

Other reasons for state restriction are based on laws known as prior appropriation, which were implemented as a first-come, first-serve basis for settlers in the Old West. Prior appropriation laws are generally applied toward groundwater and surface water situations, but some states still consider rainwater as part of the prior appropriation doctrine as well.

Health and safety concerns

Because the typical catchment surface for rainwater is the rooftop of a home, bacteria from animal feces and other harmful contaminants are generally present in rainwater. This makes it very dangerous to consume without proper filtration.

While some states still require permits for rainwater harvesting, the trend of most states seems to be shifting toward favoring of private rainwater harvesting. Colorado, the state with arguably the strictest rainwater harvesting laws, passed a bill in 2016 allowing for the collection of rainwater with a 110-gallon maximum capacity.

Organizations such as the American Rainwater Catchment Systems Association (ARCSA) work with state governments in making rainwater collection an available option for its citizens.

What you need to know

Since water rights vary from state to state it's important for you to check with your own state's legislation before setting up your rainwater harvesting system. Some states such as Arkansas, Colorado, Kansas, Oregon, Utah, and Washington may require a permit before rainwater catchment can be implemented. But the majority of states have no restriction at all while some states even encourage rainwater harvesting with incentives.

The following list contains information gathered from state websites and legislative documents and was current at the time of publication. We will do our best to keep this list updated. But because laws are constantly changing, please check with your state for further information.

Recommended Rainwater Harvesting Supplier: Rainharvest Systems

Rainharvest Systems has the largest selection of rainwater harvesting supplies and at the best prices. As a brick-and-mortar store based out of Georgia, USA, their supplies are always stocked and ready to be shipped anywhere. They're truly experts in the industry and carry only the highest quality products.

The State of Alabama considers rainwater harvesting a private property right. There are currently no regulations for rainwater harvesting in the state.

In fact, Alabama A&M and Auburn University extension services published a document encouraging the practice of rainwater collection, providing technical instructions and guidelines.

The State of Alaska does not restrict rainwater harvesting as it is a primary source of water for many residents. Groundwater harvesting, however, is regulated and can be purchased as a water right.

Due to the cold climate, certain precautions may need to be considered when collecting rainwater in Alaska.

Rainwater harvesting is legal in Arizona. Two House Bills, 2363 and 2830, support this. House Bill 2363 establishes a joint legislative study committee on macro-harvested rainwater, allowing for the study and evaluation of scientific data, costs and benefits, and potential impact on water rights. House Bill 2830, through the Department of Water Resources, allows for a city or town to establish a fund for rainwater harvesting systems.

Arizona offers tax incentives for rainwater harvesting.

The State of Arkansas allows for rainwater harvesting as long as it's used for non-potable purposes.

According to Arkansas Code Annotated § 17-38-201 (2014), the State Board of Health “shall allow the use of a harvested rainwater system used for a non-potable purpose if the harvested rainwater system is: (1) designed by a professional engineer licensed in Arkansas; (2) is designed with appropriate cross-connection safeguards; and (3) complies with Arkansas Plumbing Code.”

In 2012, the State of California passed Assembly Bill 1750, which enacted the Rainwater Capture Act of 2012, making it legal to collect rainwater so long as in compliance with the California State Water Resources Board requirements. The Bill states that residential, commercial and governmental landowners may install, maintain, and operate rain barrel systems and rainwater capture systems for specified purposes.

In 2018, the State of California passed SB-558, which excludes property taxes from the new construction of a rainwater harvesting system.

Colorado has traditionally been one of the most restrictive states for rainwater harvesting. Two laws were passed in 2009 which loosened restrictions on rainwater collection, allowing residents to use rainwater for non-potable purposes.

In 2016, House Bill 16-1005 was passed, allowing residents to collect rainwater from a catchment system on their rooftops into two rain barrels, with a combined capacity of 110 gallons. The collected rain must be used on the property where it is collected and may only be used for outdoor purposes such as lawn irrigation and gardening.

Colorado Division of Water Resources offers guidelines on rainwater collection. Colorado State University's fact sheet offers FAQs on rainwater collection.

The State of Connecticut allows the collection of rainwater from one's own property according to Section 1303 of their 2018 State Building Code.

In a document released by the Connecticut Department of Energy and Environmental protection encourages its citizens to collect rainwater and a guide by the Connecticut Department of Energy and Environmental Protection offers information on rain barrels.

The State of Delaware views rainwater harvesting as sustainable stormwater management and does not have any laws prohibiting rainwater collection but in fact sponsors incentive programs encouraging it.

The University of Delaware offers a guide for rainwater harvesting.

Rainwater collection is highly encouraged in the State of Florida with tax incentives and rebate programs being offered by several local municipalities including Manatee County. Chapter 29 of 2017 Florida Building Code addresses Nonpotable Rainwater Collection and Distribution Systems.

Orlando offers a rebate program for rainwater collection installment.

Rainwater harvesting is legal in Georgia but closely regulated by the Department of Natural Resources in the Environmental Protection Division.

According to their plumbing code, rainwater harvesting is legal as long as it is used for outdoors only.

The State of Hawaii does not have any restrictions on rainwater harvesting but in fact highly encourages it. Overseen by the Department of Health and Safety, Senate Concurrent Resolution 172 encourages county water boards to study and promote rainwater collection. Chapter 15 of their plumbing code states, "a permit is not required for exterior rainwater catchment systems used for outdoor drip and subsurface irrigation with a maximum storage capacity of 360 gallons."

The Honolulu Board of Water Supply offers incentives for rain barrel installment.

Idaho does not have any regulations on rainwater capture except for rainwater which has entered natural waterways.

Article 15 of the Idaho Constitution states, "the right to divert and appropriate the unappropriated waters of any natural stream to beneficial uses shall never be denied…"

Rainwater harvesting is legal in Illinois but with two major statutes. The Green Infrastructure for Clean Water Act which relates to water conservation, efficiency, infrastructure, and management while promoting rainwater harvesting. House Bill 991 (2011) amended the Homeowners’ Solar Rights Act.

It requires that within 120 days after a homeowners’ association, the association shall adopt an energy policy statement regarding: (i) the location, design, and architectural requirements of solar energy systems; and (ii) whether a wind energy collection, rain water collection, or composting system is allowed, and, if so, the location, design, and architectural requirements of those systems.

Rainwater harvesting is legal in Indiana.

The State government encourages the act of rainwater collection and even has useful information on rain barrels on their website.

Iowa has no regulations on rainwater collection.

The Iowa Department of Natural Resources provides information on stormwater on their website.

It is legal to harvest rainwater in Kansas, but a permit issued by the Department of Agriculture may be required if used for anything other than domestic purposes.

The Kansas Water Appropriation Act protects the people's rights to harvest rainwater if used for domestic purposes but doesn't consider it a viable source for drinking.

Kentucky does not have any restrictions on rainwater collection.

Information on how to construct a rain barrel can be found on their website.

Rainwater collection is legal in Louisiana and in fact, encouraged.

The New Orleans City Council states that all cisterns must be covered.

There are no regulations for rainwater harvesting in the State of Maine.

Some cities such as Portland, issue stormwater fees to pay for improved stormwater systems for the city.

Rainwater harvesting is legal in Maryland.

Montgomery county offers incentives for rainwater collection.

Rainwater harvesting is legal and encouraged by the State of Massachusetts.

The Boston Water and Sewer Commission offers a guide to best stormwater practices.

Under the Cost Effective Governmental Energy Use Act, rainwater harvesting, along with other cost-efficient procedures, is legal and encouraged in the state of Michigan.

The City of Detroit offers incentives for stormwater collection.

Rainwater harvesting is legal and encouraged in the State of Minnesota.

Washington County offers incentives for water conservation on property.

The State of Mississippi encourages rainwater harvesting and provides many resources to do so.

The Department of Environmental Quality's stormwater guide has a section on rain barrel usage.

Rainwater harvesting is legal in Missouri and highly encouraged.

Missouri SB 782, Section 640.648 states "landowners shall also have the right to have and use systems for potable water, and systems for rainwater collection."

Rainwater harvesting is legal in Montana and highly encouraged. Section Three of Article IX in Montana's Constitution states, “all existing rights to the use of any waters for any useful or beneficial purpose are hereby recognized and confirmed.”

Montana State University offers a guide to rainwater harvesting.

Rainwater harvesting is legal in Nebraska and is in fact promoted by many Universities.

Section P2912 of the  Nonpotable Rainwater Collection and Distribution Systems states that rainwater harvesting is encouraged for outdoor, domestic use.

Nevada passed NB74 in June 2017, allowing for the collection of rainwater under the grant of a water right without having to follow the "use it or lose it" doctrine, however, some restrictions are still in place.

Assembly Bill 138 states that rainwater may be collected without a water right or permit to appropriate water as long as provisions apply.

Section P2912 of the Nonpotable Rainwater Collection and Distribution Systems states that some of these provisions are:

• must be collected from a single-family dwelling above-ground rooftop
• must be used for non-potable domestic use only
• must not conflict with existing water rights
• storage capacity must be 20,000-gallons or less
• capture area must be an acre or less

Assembly Bill 198 states the Legislative Committee on Public Lands will conduct studies on water conservation and alternative sources of water for communities in the State. This includes a comprehensive review of alternative sources of water, including capturing rainwater amongst other things.

Rainwater harvesting is completely legal in New Hampshire and is in fact encouraged by the state, offering information on rain barrel design.

The Soak Up the Rain project is a community program that encourages rainwater harvesting.

Rainwater harvesting is legal in New Jersey. and offers a rain barrel rebate program.

Their municipal guide encourages rainwater harvesting and provides education resources.

Rainwater harvesting is legal and highly encouraged in the State of New Mexico.

Albuquerque offers financial rebates for rainwater harvesting according to the number of gallons collected. Santa Fe offers financial rebates for small rain barrels and large cisterns.

Rainwater harvesting is legal, encouraged, and even taught in the State of New York. This guide explains how to effectively harvest rainwater for outdoor and indoor use.

Potable Water Systems codes states that UV purification or chlorination must be conducted if the rainwater is intended for consumption.

Rainwater harvesting is legal in North Carolina, however, there are two laws regulating it. 

House Bill 609 (2011) says that the Department of Environment and Natural Resources will provide statewide assistance on water efficiency and will ensure best management practices for conservation, which include water reuse and harvesting rainwater. Senate Bill 163 (2014) recognizes the benefits of rainwater for the future water supply of the state. This means homeowners can legally capture rainwater as long as local guidelines are kept.

New Hanover County offers an incentive program for stormwater collection.

While North Dakota does have some strict laws regarding other water sources, rainwater harvesting is legal and encouraged for domestic use.

If rainwater collection is intended for irrigation for more than 5-acres of land, or is intended for industrial or commercial use, a permit may be required.

The State Water Commission offers a guide to water usage.

Rainwater harvesting is legal in Ohio, even for potable purposes. Ohio Rev. Code §3701.344 states that private water systems that provide drinking water to fewer than twenty-five people are regulated by the Ohio Department of Health.

Ohio Department of Health offers plans for developing rainwater harvesting systems.

The University of Toledo offers rainwater harvesting resources.

Rainwater harvesting is legal in Oklahoma. Under House Bill 3055, the Water for 2060 Act initiates grants for water conservation projects, to serve as models for other communities in the state. These projects may include community conservation demonstration projects, recycling and reuse of water, and information campaigns on capturing harvested rainwater.

OSU offers design systems for rainwater harvesting.

Rainwater harvesting is legal in Oregon, but may only be collected from a catchment system on rooftop surfaces.  The state gives some approval for alternate methods of construction of rainwater harvesting systems, but legal advice should be sought before attempting to construct any system on private property.

The Bureau of Development Services states that harvested rainwater is not considered potable (drinkable) water.

Oregon's water laws are based on the doctrine of prior appropriation and requires most water surface water uses to obtain a permit. However, rainwater harvesting when collected on a rooftop does not require a permit.

Portland offers stormwater rewards for rain collection as well as the downspout disconnect program.

The City of Eugene offers guidelines on capturing rainwater on site.

Rainwater collecting is legal in Pennsylvania and is in fact encouraged by State Universities, but does not consider it to be safe drinking water.

The City of Philadelphia offers stormwater grants for responsible rainwater collection.

Rhode Island provides incentives for those who harvest rainwater. House Bill 7070 (2012) creates a tax credit to individuals or businesses for the installation of a cistern to collect rainwater.

A state income tax credit of 10 percent of the cost of installing the cistern is credited to those who participate. A cistern is defined as a container holding fifty or more gallons of diverted rainwater or snow melt, either above or below ground.

Rhode Island plumbing code does state that rainwater may only be collected from above-ground impervious roof surfaces from approved materials.

It is completely legal to harvest rainwater in South Carolina, given that they're collected by above-ground rooftop surfaces, as stated by the plumbing code.

SC offers a rainwater harvesting guide.

While South Dakota does have quite a few statutes on water rights, rainwater harvesting is completely legal a long as it doesn't exceed 25,920 gallons of water per day.

Anything beyond that would require a permit.

Rainwater harvesting is legal in Tennessee. SB 2417 / HB 1850 (Enacted) allows for the use of green infrastructure practices which includes rainwater harvesting systems. According to this bill, rainwater can be collected for domestic purposes as long as it's not for potable use.

Nashville offers a stormwater management manual.

It is legal to harvest rainwater in Texas. There are several provisions in House Bill 3391, most notably:

• the catchment system must be incorporated into the design of the building
• a written notice must be given to the municipality or owner of the public water supply system
• rainwater used for indoor potable purposes must be properly treated as such

State of Texas offers guidelines for rainwater harvesting and offers tax exemptions.

The State of Utah authorizes the direct collection of rainwater on land owned or leased by the person responsible for the collection.

According to Senate Bill 32 (2010), a person registered with the Division of Water Resources cannot store more than 2,500 gallons of rainwater. If unregistered, no more than two containers may be used, and the maximum capacity of any one container may not exceed 100 gallons (Utah Code Ann. §73-3-1.5)

Rainwater collection is legal in the State of Vermont. as long as its used for non-potable, outdoor purposes.

Vermont offers a guide to stormwater management.

In Virginia, rainwater harvesting is allowed for non-potable or outdoor uses.

Senate Bill 1416 (2001) established the Alternative Water Supply Assistance Fund, providing an income tax credit to those who install rainwater harvesting systems.

The State of Virginia also requires the development of rainwater harvesting guidelines to reduce demands on water supply systems and to promote conservation (Va. Code § 32.1-248.2).

Rainwater collection is legal in the State of Washington and even authorizes counties to reduce rates for stormwater control facilities that utilize rainwater harvesting, by 10 percent or more according to Wash. Rev. Code §36.89.080.

Residents of Washington state may harvest rainwater without a permit as long as:

• it's used on the property from which it was collected
• it's collected on an existing rooftop

The Washington Department of Ecology issued an Interpretive Policy Statement clarifying that a water permit is not required for rooftop rainwater harvesting.

Rainwater harvesting is legal in West Virginia, as long as it's for non-potable use.

The WV Department of Environmental Protection offers guidelines on how to build a rain barrel as well as a stormwater management manual.

Rainwater harvesting is legal in Wisconsin for non-potable outdoor uses.

Residents are not required to obtain a permit as long as certain guidelines are followed:

• the collection tank must be stored above ground
• the rainwater system must not be directly connected to the public water supply
• the water supply must be used for outdoor, non-potable purposes only

Rainwater harvesting is legal in Wyoming for non-potable, outdoor use.

The City of Gillette offers a rain barrel rebate program.