1. Arkansas: Rainwater harvesting systems are allowed for non-potable purposes only if they are designed by a professional engineer licensed in Arkansas, designed with appropriate cross-connection safeguards, and comply with the Arkansas Plumbing Code.
2. Colorado: Without a water permit, Colorado residents are legally allowed to store up to 150-gallons for rainwater harvesting systems that comply with the Colorado Water Conservation Board.
3. Kansas: It’s not illegal to harvest rainwater in Kansas, but you may need to apply for a permit to do so if you plan on using the water for anything other than for domestic purposes.
4. Nevada: There are restrictions on using rainwater for anything other than for wildlife but SB74 created a few changes including allowing the use of a small-scale rainwater system without having to prove the “use it or lose it” doctrine and expanding the use for the water.
5. Oregon: While rainwater harvesting is allowed in Oregon, there are a lot of statutes regulating it including specifying only rooftop collection.
6. Utah: Utah allows for rainwater harvesting on land owned or leased by the person responsible for the collection. Must register system with Utah Division of Water Rights
7. Washington: Washington allows rooftop rainwater harvesting for domestic use without a water permit. Other applications may require a permit.
One common Uniform Plumbing Code that is often cited by states is Chapter 13 Non-potable Water Systems, Section 1303 Non-potable Rainwater Collection, and Distribution Systems.
SECTION 1303 NON-POTABLE RAINWATER COLLECTION AND DISTRIBUTION SYSTEMS
1303.1 General. The provisions of Section 1303 shall govern the construction, installation, alteration, and repair of rainwater collection and conveyance systems for the collection, storage, treatment, and distribution of rainwater for non-potable applications, as permitted by the jurisdiction.
1303.2 Collection surface. Rainwater shall be collected only from above-ground impervious roofing surfaces constructed from approved materials. Collection of water from vehicular parking or pedestrian surfaces shall be prohibited except where the water is used exclusively for landscape irrigation. Overflow and bleed-off pipes from roof-mounted appliances including but not limited to evaporative coolers, water heaters, and solar water heaters shall not discharge onto rainwater collection surfaces.
Which states allow rainwater as a source for potable, drinking water?
7 states include regulations on rainwater as a potable drinking water source (Texas, Mississippi, North Carolina, Ohio, Oregon recently, Virginia, Hawaii)
Texas offers a tax exemption for rainwater harvesting equipment.