Rainwater Harvesting: Ontario vs Rialto
How do rainwater harvesting rules compare between Ontario, CA and Rialto, CA?
Ontario and Rialto have similar restriction levels.
Ontario, CA
San Bernardino County
California's Rainwater Capture Act (AB 1750) lets Ontario residents collect roof rainwater for outdoor use without a permit for simple barrels. Large cisterns and indoor use require plumbing permits.
View full Ontario rules →Rialto, CA
San Bernardino County
Rainwater capture is legal and encouraged in California under the Rainwater Capture Act of 2012 (AB 1750). Rialto requires no permit for rain barrels up to 5,000 gallons used outdoors. Larger cisterns and any indoor/potable use require plumbing permits and backflow protection per the California Plumbing Code.
View full Rialto rules →Key Facts Comparison
| Fact | Ontario | Rialto |
|---|---|---|
| State law | Rainwater Capture Act (AB 1750) | - |
| Small barrels | Generally no permit | - |
| Large cisterns | Plumbing permit required | - |
| Indoor use | Permit and backflow device | - |
| Mosquito control | Screen all openings | - |
| Rain Barrel ≤360 gal | - | No permit required |
| Cistern >360 gal | - | Plumbing permit required |
| State Law | - | Water Code §10573 (AB 1750) |
| Code | - | CPC Ch. 15 / Ch. 17 |
Highlighted rows indicate differences between cities.
Ontario FAQ
Do I need a permit for a 55-gallon rain barrel in Ontario?
Typically no, if it is above-ground, gravity-fed, screened against mosquitoes, and used only for outdoor irrigation.
Can I plumb rainwater to flush my toilets?
Yes, but only with a plumbing permit, a licensed contractor, Appendix K-compliant treatment, and approved backflow prevention.
Rialto FAQ
Do I need a permit for a rain barrel in Rialto?
No. Rain barrels up to 360 gallons (or up to 5,000 gallons of aggregate storage in some readings of CPC 1502.4) used for outdoor irrigation only do not require a permit. Larger systems or any indoor connection require a Building Safety Division permit.
Can I harvest rainwater to drink?
Potable use of harvested rainwater is not permitted under the California Plumbing Code without an engineered treatment system and Health Department approval. Stick to landscape irrigation and toilet flushing (with dual piping).
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