Marion County, OR Landscaping Rules: Rainwater Harvesting (2026)
Key Facts
- County ordinance
- None restricting rain barrels
- Rooftop collection
- No water right needed
- State law
- ORS 537.141
- Permit triggers
- Large tanks, indoor plumbing
- Register with OWRD
- Systems over 15,000 gallons
Summary
Oregon law lets you collect rain and snowmelt from a rooftop or other artificial impervious surface without a water right. Marion County has no ordinance banning rain barrels; large tanks or indoor plumbing may need a building or plumbing permit.
The following water uses do not require an application under ORS 537.130 or 537.615, a water right permit under ORS 537.211 or a water right certificate under ORS 537.250: ... (h) The collection of precipitation water from an artificial impervious surface and the use of such water.
Full Breakdown
Under Oregon Revised Statutes 537.141, collecting precipitation from an artificial impervious surface, such as a rooftop, and using that water does not require a water-right application, permit or certificate from the Oregon Water Resources Department. Marion County imposes no separate prohibition on residential rain barrels or cisterns. What is still regulated is scale and plumbing: exterior, non-potable irrigation systems generally need no plumbing permit, but larger storage (roughly over 5,000 gallons) may require a building permit, systems over 15,000 gallons must register with OWRD, and using rainwater for drinking triggers design and plumbing-permit requirements. You may not divert a stream, ditch or canal without a water right.
Violations & Fines
No county penalty for rooftop rainwater collection. Skipping a required building or plumbing permit for a large or plumbed system, or diverting a natural watercourse without a water right, can violate state building code or OWRD water law.
Frequently Asked Questions
Can I put rain barrels on my Marion County home?
When do I need a permit?
Sources & Official References
Other rules in Marion County
Compare Marion County to another location·View the Oregon landscaping rules overview
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