Kailua vs Mililani Mauka
How do rainwater harvesting rules compare between Kailua, HI and Mililani Mauka, HI?
Kailua and Mililani Mauka have similar restriction levels.
Kailua, HI
Honolulu County
Kailua residents can collect rainwater for outdoor irrigation without a permit; the Board of Water Supply offers rebates for rain barrels on windward lots.
View full Kailua rules →Mililani Mauka, HI
Honolulu County
Mililani Mauka homeowners may install rain barrels without a Honolulu permit; small outdoor catchment up to 360 gallons is exempt under state plumbing code.
View full Mililani Mauka rules →Key Facts Comparison
| Fact | Kailua | Mililani Mauka |
|---|---|---|
| Permit threshold | 360 gallons storage | - |
| Code reference | Hawaii Plumbing Code Ch. 16 | - |
| Rebates | BWS rain barrel program | - |
| Indoor use | Requires plumbing permit | - |
| City code | - | No specific ordinance |
| Plumbing code | - | Up to 360 gallons exempt |
| Incentive | - | BWS rebate programs |
| HOA layer | - | Mauka design review |
Highlighted rows indicate differences between cities.
Kailua FAQ
Can I install rain barrels on my Kailua home?
Yes. Exterior barrels up to 360 gallons for outdoor irrigation are allowed without a permit. BWS offers rebates to offset purchase costs.
Can I plumb harvested water into my Kailua kitchen?
Only with a plumbing permit and proper backflow protection. Indoor use is treated as a non-potable supply under the Hawaii Plumbing Code.
Mililani Mauka FAQ
Do I need a permit for a rain barrel in Mililani Mauka?
No. Residential catchment under 360 gallons is exempt under the Hawaii Plumbing Code, and Honolulu has no specific residential catchment ordinance.
Will the Mauka HOA let me install a rain barrel?
Usually yes with screening. Submit your plans to the Mililani Mauka Community Association architectural review to confirm placement and color requirements.
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