Rainwater Harvesting - Rules, Regulations, and Restrictions by state.

by Superesse Staff February 27, 2023

Below is a composition of laws, regulations, and restrictions on citizens' ability to collect and store rainwater for gardening, irrigation, and consumption.

This is by no means an exhaustive guide. The onus is on the individual to conduct their own thorough research for their area and intent. We've focused on state level guidance but local districts may impose their own regulations. If you're planning or already practicing rainwater collection, it might help to further research.

Also, after this guide we'll discuss the basics of collecting and storing water.

》Alabama

Regulated: No

Restrictions: No

Permit required: No

Quantity: N/A

Reference: https://www.energy.gov/eere/femp/rainwater-harvesting-regulations-map

》Alaska

Regulated: No

Restrictions: No

Permit required: No

Quantity: N/A

Reference: https://www.energy.gov/eere/femp/rainwater-harvesting-regulations-map

》Arizona

Regulated: Yes. Check county regulations. Some incentives may be offered to residents.

Restrictions: Some building restrictions apply to new construction. Check local regulations for specific information.

Permit required: Some counties require certifications for installations.

Quantity: Check local regulations

Reference: https://new.azwater.gov/conservation/landscaping

》Arkansas

Regulated: Yes

Restrictions: 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: (1) Is designed by a professional engineer licensed in Arkansas; (2) Is designed with appropriate cross-connection safeguards; and (3) Complies with the Arkansas Plumbing Code.

Permit required: Yes

Quantity: N/A

Reference: https://law.justia.com/codes/arkansas/2017/title-17/subtitle-2/chapter-38/subchapter-2/section-17-38-201/

》California

Regulated: Yes.

Restrictions: Varies by use case.

Permit required: At the state level, no. But check by county.

Quantity: The state level does not regulate a quantity. Check county rules.

Reference: https://bayareaanswers.com/is-it-illegal-to-collect-rainwater-in-california/

https://leginfo.legislature.ca.gov/faces/codes_displayText.xhtml?lawCode=WAT&division=6.&title=&part=2.4.&chapter=&article=

https://leginfo.legislature.ca.gov/faces/billTextClient.xhtml?bill_id=201120120AB1750

》Colorado

Regulated: Yes

Restrictions: Yes

Permit required:

Quantity: 110 gallons for outdoor use only. A residence that relies on a well may collect an unlimited amount for indoor/outdoor use.

Reference: https://www.energy.gov/eere/femp/rainwater-harvesting-regulations-map

》Connecticut

Regulated: No

Restrictions: No

Permit required: No

Quantity: N/A

Reference: https://www.energy.gov/eere/femp/rainwater-harvesting-regulations-map

》Delaware

Regulated: No

Restrictions: No

Permit required: No

Quantity: N/A

Reference: https://www.energy.gov/eere/femp/rainwater-harvesting-regulations-map

》Florida

Regulated: No

Restrictions: No

Permit required: No

Quantity: N/A

Reference: https://www.energy.gov/eere/femp/rainwater-harvesting-regulations-map

》Georgia

Regulated: Yes

Restrictions: Regulations are in place allowing rainwater harvesting; however, no specific technical resources or incentives are provided

Permit required: N/A

Quantity: The state level does not regulate a quantity. Check county rules.

Reference: https://www.energy.gov/eere/femp/rainwater-harvesting-regulations-map

》Hawaii

Regulated: Yes

Restrictions: Check local guidance

Permit required: N/A

Quantity: N/A

Reference: https://www.energy.gov/eere/femp/rainwater-harvesting-regulations-map

》Idaho

Regulated: Yes

Restrictions: Regulations are in place allowing rainwater harvesting; however, no specific technical resources or incentives are provided

Permit required: Yes

Quantity: N/A

Reference: https://www.harvesth2o.com/adobe_files/Idaho_Ltr%20Sen%20Schroeder%20081108.pdf

》Illinois

Regulated: Yes

Restrictions: Requires rainwater harvesting collection systems and rainwater harvesting distribution systems to be (A) used only for non-potable uses and (B) constructed in accordance with the Illinois Plumbing Code. Defines "rainwater harvesting collection system" and "rainwater harvesting distribution system"

Permit required: Check local guidance.

Quantity: Rain barrels/cisterns containing more than 55 gallons must have proper structural foundations.

Reference:https://www.chicago.gov/content/dam/city/depts/water/general/Engineering/SewerConstStormReq/2016StormwaterRegulations.pdf

》Indiana

Regulated: No

Restrictions: No statewide rainwater harvesting regulations; check county for local incentives

Permit required: Check local guidance

Quantity: N/A

Reference: https://www.energy.gov/eere/femp/rainwater-harvesting-regulations-map

》Iowa

Regulated: No

Restrictions: No

Permit required: No

Quantity: N/A

Reference: https://www.energy.gov/eere/femp/rainwater-harvesting-regulations-map

》Kansas

Regulated: Yes

Restrictions: Yes

Permit required: Yes, check local regulations

Quantity: Check local regulations

Reference: https://agriculture.ks.gov/divisions-programs/dwr/water-appropriation/water-law-basics

》Kentucky

Regulated: No

Restrictions: No

Permit required: No

Quantity: N/A

Reference: https://www.energy.gov/eere/femp/rainwater-harvesting-regulations-map

》Louisiana

Regulated: No

Restrictions: No

Permit required: No

Quantity: N/A

Reference: https://www.energy.gov/eere/femp/rainwater-harvesting-regulations-map

》Maine

Regulated: No

Restrictions: No

Permit required: No

Quantity: N/A

Reference: https://www.energy.gov/eere/femp/rainwater-harvesting-regulations-map

》Maryland

Regulated: No

Restrictions: No

Permit required: No

Quantity: N/A

Reference: https://www.energy.gov/eere/femp/rainwater-harvesting-regulations-map

》Massachusetts

Regulated: No

Restrictions: No

Permit required: No

Quantity: N/A

Reference: https://www.energy.gov/eere/femp/rainwater-harvesting-regulations-map

》Michigan

Regulated: No

Restrictions: No

Permit required: No

Quantity: N/A

Reference: https://www.energy.gov/eere/femp/rainwater-harvesting-regulations-map

》Minnesota

Regulated: Yes

Restrictions: Regulated through the Minnesota Plumbing Board, which requires permitting and code compliance; check for local incentives

Permit required: Check local guidance

Quantity: n/a

Reference: https://stormwater.pca.state.mn.us/index.php/Design_criteria_for_stormwater_and_rainwater_harvest_and_use/reuse#Identify_required_permits_and_applicable_codes

》Mississippi

Regulated: No

Restrictions: No

Permit required: No

Quantity: N/A

Reference: https://www.energy.gov/eere/femp/rainwater-harvesting-regulations-map

》Missouri

Regulated: No

Restrictions: No

Permit required: No

Quantity: N/A

Reference: https://www.energy.gov/eere/femp/rainwater-harvesting-regulations-map

》Montana

Regulated: No

Restrictions: No

Permit required: No

Quantity: N/A

Reference: https://www.energy.gov/eere/femp/rainwater-harvesting-regulations-map

》Nebraska

Regulated: No

Restrictions: No

Permit required: No

Quantity: N/A

Reference: https://www.energy.gov/eere/femp/rainwater-harvesting-regulations-map

》Nevada

Regulated: No

Restrictions: Check county requirements

Permit required: Check county requirements

Quantity: 20,000 gallons

Reference: https://www.leg.state.nv.us/NRS/NRS-533.html#NRS533Sec070

》New Hampshire

Regulated: No

Restrictions: No

Permit required: No

Quantity: N/A

Reference: https://www.energy.gov/eere/femp/rainwater-harvesting-regulations-map

》New Jersey

Regulated: No

Restrictions: No

Permit required: No

Quantity: N/A

Reference: https://www.energy.gov/eere/femp/rainwater-harvesting-regulations-map

》New Mexico

Regulated: Yes

Restrictions: Yes. Outdoor use, no regulations. Indoor, check county requirements

Permit required: Check county requirements

Quantity: Check county requirements

Reference: https://www.ose.state.nm.us//WUC/wuc_rainHarvesting.php

》New York

Regulated: No

Restrictions: No

Permit required: No

Quantity: N/A

Reference: https://www.energy.gov/eere/femp/rainwater-harvesting-regulations-map

》North Carolina

Regulated: No

Restrictions: No

Permit required: No

Quantity: N/A

Reference: https://www.energy.gov/eere/femp/rainwater-harvesting-regulations-map

》North Dakota

Regulated: No

Restrictions: No

Permit required: No

Quantity: N/A

Reference: https://www.energy.gov/eere/femp/rainwater-harvesting-regulations-map

》Ohio

Regulated: No

Restrictions: No

Permit required: No

Quantity: N/A

Reference: http://codes.ohio.gov/orc/3701.344

》Oklahoma

Regulated: Yes

Restrictions: Check local guidance

Permit required: Check local guidance

Quantity: Check local guidance

Reference: https://www.energy.gov/eere/femp/rainwater-harvesting-regulations-map

》Oregon

Regulated: Yes.

Restrictions: Location/use dependent

Permit required: Check local/use

Quantity: Check with county regulations.

Reference: https://www.oregon.gov/bcd/documents/brochures/3660.pdf

https://www.oregon.gov/bcd/codes-stand/Pages/plumbing.aspx

》Pennsylvania

Regulated: No

Restrictions: No

Permit required: No

Quantity: N/A

Reference: https://www.energy.gov/eere/femp/rainwater-harvesting-regulations-map

》Rhode Island

Regulated: No

Restrictions: No

Permit required: No

Quantity: N/A

Reference: https://www.energy.gov/eere/femp/rainwater-harvesting-regulations-map

》South Carolina

Regulated: No

Restrictions: No

Permit required: No

Quantity: N/A

Reference:

https://www.energy.gov/eere/femp/rainwater-harvesting-regulations-map

》South Dakota

Regulated: No

Restrictions: No

Permit required: No

Quantity: N/A

Reference: none

》Tennessee

Regulated: No

Restrictions: No

Permit required: No

Quantity: N/A

Reference: https://www.energy.gov/eere/femp/rainwater-harvesting-regulations-map

》Texas

Regulated: Yes

Restrictions: Plans for new home construction require permitting if rainwater harvesting is to be used.

Permit required: No

Quantity: N/A

Reference: https://www.energy.gov/eere/femp/rainwater-harvesting-regulations-map

》Utah

Regulated: Yes

Restrictions: Yes

Permit required: <100 gallons, No. Anything over, yes.

Quantity: 2,500 gallons

Reference: https://www.waterrights.utah.gov/forms/rainwater.asp

》Vermont

Regulated: Yes

Restrictions: Check local guidance

Permit required: Check local guidance

Quantity: Check local guidance.

Reference:https://dec.vermont.gov/sites/dec/files/documents/VermontStormwaterManagementManualRule_Ch36_2017_Final_2016-12-20.pdf

》Virginia

Regulated: Yes

Restrictions: Check local guidance

Permit required: Check local guidance

Quantity: Check local guidance.

Reference: https://www.energy.gov/eere/femp/rainwater-harvesting-regulations-map

》Washington

Regulated: Yes. However, the state may offer stormwater fee incentives for the collection of rainwater.

Restrictions: Varies based on local/use.

Permit required: For specific applications, and county by county basis.

Quantity: Varies depending on use case.

Reference: https://ecology.wa.gov/Water-Shorelines/Water-supply/Water-recovery-solutions/Rainwater-collection

》West Virginia

Regulated: No

Restrictions: No

Permit required: No

Quantity: N/A

Reference: https://www.energy.gov/eere/femp/rainwater-harvesting-regulations-map

》Wisconsin

Regulated: No

Restrictions: No

Permit required: No

Quantity: N/A

Reference: https://www.energy.gov/eere/femp/rainwater-harvesting-regulations-map

》Wyoming

Regulated: No

Restrictions: No

Permit required: No

Quantity: N/A

Reference: https://www.energy.gov/eere/femp/rainwater-harvesting-regulations-map

Sources (other): https://watershedcommittee.org/wp-content/uploads/2013/06/Rainwater-Manual.pdf | https://new.azwater.gov/sites/default/files/media/Harvesting%20Rainwater_0.pdf

RAINWATER BASICS

The first step is to determine the collection area. The collection area can be any flat or sloping surface that can catch rainwater such as rooftops or home-made funnels systems.
Since gutters and downspouts are most commonly used, we'd recommend this for beginners. Use existing roof gutters to collect water then use downspouts that lead to a storage container. There are advance options you could consider such as a "first-flush" system that diverts the first few gallons away from your cistern so that less airborne pollutants are collected. Consider adding multiple collection downspouts and cisterns/barrels to increase your collection.
Choose a container to store the collected rainwater. The container should be made of a food-grade material such as plastic. There are pretty cheap (or free) containers if you search in online marketplaces (we found a 275 gallon tank that use to old sucrose syrup). It should have a tight-fitting lid to prevent debris and insects from entering. Consider installing your cistern/barrel on an elevated platform to improve water pressure. You can also add a pump so that you can elevate the waterflow up to a sink or shower. They're fairly cheap, we used both a 1.5gpm and 7gpm pump and found 1.5 was all we needed. We also hooked ours to a propane water heater. It is powered by a bank of marine deepcycle batteries.
Install a filter at the downspout to prevent leaves, debris, and other contaminants from entering the storage container. Plumbing experience is helpful but if you're just looking to collect non-potable water (like for your garden) then really anything will work if you can divert water into your container. Clean out your rain barrel or cistern regularly to prevent debris and insects from accumulating. A bleach additive or irriator may help prevent residue build up and longevity of your water.
Install an overflow system to divert excess water away from the storage container in case of heavy rainfall or infrequent usage.
Use the collected water for non-potable purposes such as watering plants, washing cars, or flushing toilets. Add a filter beyond the outlet if you plan on drinking the water. Of simply filter it yourself, then boil it or treat it with purification additives. Depending on your system you bay be able to drink it even after a rudimentary filtration.