Quick answer

Yes. Rain barrels are completely unrestricted in Oregon; permits apply only to large cistern systems.

What Oregon law says

Oregon draws a line by system size. Standard rain barrels unrestricted. Large cisterns require a water right permit. If you are putting one or two barrels under a downspout, nothing about Oregon law affects you.

How much water a Oregon roof can collect

Oregon averages about 43 inches of rain per year. On a typical 1,200 square foot roof at 85% collection efficiency, that works out to roughly 27,300 gallons a year currently running into your storm drain. A single one-inch storm delivers about 635 gallons, enough to fill 13 standard 50-gallon barrels.

43"

Average annual rainfall in Oregon.

27,300

Gallons per year from a typical 1,200 sq ft roof.

$328

Approximate annual value at municipal water rates.

Your roof and rainfall will differ; run your exact numbers in the rainwater calculator.

The right setup for Oregon’s climate

At roughly 43 inches of rain a year, Oregon is a wet-climate state; your barrel will refill constantly. Prioritize a sealed, mosquito-proof design and plan the overflow path. A 50-gallon barrel with a diverter that returns excess water to the downspout is the right call.

Our pick for Oregon

Rain Wizard 50 + Diverter Kit, reviewed against our independent testing criteria. See all six models side by side.

Common questions

Is it illegal to collect rainwater in Oregon?
Yes. Rain barrels are completely unrestricted in Oregon; permits apply only to large cistern systems. This is educational information, not legal advice.
Do I need a permit for a rain barrel in Oregon?
Not for a barrel. Standard rain barrels unrestricted. Large cisterns require a water right permit.
Does Oregon offer incentives for rainwater harvesting?
Oregon has no statewide incentive program at this time, but some utilities and municipalities offer local rain barrel rebates. Check with your water utility.

Sources

  1. Rainplan, 50-State Rainwater Collection Guide (2026)
  2. State statutes and water agency guidance for Oregon
  3. NOAA National Centers for Environmental Information, annual precipitation normals
  4. US EPA WaterSense, Outdoor Water Use fact sheet

Educational content, not legal advice. Laws change; confirm current rules with your state water agency.