Rainwater Harvesting: Castro Valley vs Hayward
How do rainwater harvesting rules compare between Castro Valley, CA and Hayward, CA?
Castro Valley and Hayward have similar restriction levels.
Castro Valley, CA
Alameda County
Rainwater harvesting is legal and encouraged in Alameda County under CA Rainwater Capture Act of 2012 (AB 1750). Rain barrels under 5,000 gallons for landscape irrigation generally need no permit.
View full Castro Valley rules →Hayward, CA
Alameda County
Rainwater harvesting is encouraged. Rain barrels up to 5,000 gallons are permit-exempt under California Rainwater Capture Act.
View full Hayward rules →Key Facts Comparison
| Fact | Castro Valley | Hayward |
|---|---|---|
| State authorization | AB 1750 (2012) | - |
| Permit-free | Under 5,000 gallons surface | - |
| Large systems | Plumbing permit required | - |
| Rebates | EBMUD, ACWD offer | EBMUD WaterSmart |
| Use | Non-potable landscape | - |
| No permit | - | Under 5,000 gal, outdoor use |
| Over 5,000 gal | - | Plumbing permit |
| Screen | - | 1/16 inch required |
| Overflow | - | To pervious area |
Highlighted rows indicate differences between cities.
Castro Valley FAQ
Can I drink harvested rainwater?
Not without extensive treatment and permitting; rainwater harvesting in California is generally limited to non-potable uses like irrigation and toilet flushing.
Are rebates available?
Yes, both EBMUD and ACWD periodically offer rebates on rain barrels and larger cisterns; check their conservation pages for current programs.
Hayward FAQ
Can I use rainwater inside my home?
Only with a permitted plumbing system that meets California Plumbing Code Chapter 17 treatment standards.
How big can my rain barrel be?
Up to 5,000 gallons without a permit for gravity-fed outdoor irrigation.
Compare other topics
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