RoofRainYield

Independence, OR rainwater: 33,278 gallons off a roof

Independence, OR: gallons off the roof each year

33,278gallons a year

That is a 1,500 sq ft asphalt roof under Independence, OR's normal 41.9 inches of rain, about 795 gallons for every inch that falls.

Independence, OR has gaps between storms long enough to drain a single barrel. Around 550 gallons of storage catches most of what is worth catching.

Rainfall: NOAA 1991-2020 climate normals, the Monmouth 0.9 Se station (1.4 mi away). Independence, OR ranks 38th wettest of the 57 cities covered in Oregon.

Month by month in Independence

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan5.974,745
Feb4.563,624
Mar4.563,624
Apr3.272,599135
May2.822,241191
Jun1.361,081373
Jul0.34270500
Aug0.56445473
Sep1.531,216352
Oct3.843,05264
Nov6.294,999
Dec6.775,381

Dec is the wettest month (6.77 in, 5,381 gal off the roof); Jul the driest (0.34 in). Garden shortfall is what a 200 sq ft vegetable bed needs beyond the rain that lands on it, April to October.

What size rain barrel for Independence

Best fit: a 550-gallon tote or tank, which delivers about 1,873 gallons to the garden in a normal year (89.8% of its need).

If you set one up, link barrels with a short hose at the base so they fill and drain together, and check the overflow points away from the house.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal81731,097
110 gal1,16630,747
165 gal1,33130,582
275 gal1,64230,272
550 gal1,87330,040
1,000 gal1,87330,040
1,500 gal1,87330,040
2,500 gal1,87330,040
5,000 gal1,87330,040

Simulated storm by storm through a normal year using the station's count of days with 0.1 in or more of rain each month.

Is rainwater collection legal in Oregon?

Collecting and using rain from an artificial impervious surface (e.g. a rooftop) is an exempt use: no water right application, permit or certificate needed. Statute sets no storage cap in this section.

Checked against the current source on 2026-11-06. Source