RoofRainYield

Redmond, OR rainwater: 8,441 gallons off a roof

Rainwater from a roof in Redmond, OR

8,441gallons a year

That is a 1,500 sq ft asphalt roof under Redmond, OR's normal 10.6 inches of rain, about 795 gallons for every inch that falls.

Redmond, 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 Redmond Air Ctr station (1.7 mi away). Redmond, OR ranks 53rd wettest of the 57 cities covered in Oregon.

Month by month in Redmond

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan2.101,669
Feb1.15914
Mar0.64509
Apr0.75596449
May1.00795418
Jun0.72572453
Jul0.40318492
Aug0.38302495
Sep0.66525460
Oct0.65517461
Nov1.24986
Dec0.93739

Jan is the wettest month (2.10 in, 1,669 gal off the roof); Aug the driest (0.38 in). Garden shortfall is what a 200 sq ft vegetable bed needs beyond the rain that lands on it, April to October.

Barrel or cistern in Redmond?

Best fit: a 550-gallon tote or tank, which delivers about 2,884 gallons to the garden in a normal year (89.3% of its need).

If you buy one, 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 gal7707,281
110 gal1,4996,552
165 gal1,9736,078
275 gal2,5255,525
550 gal2,8845,167
1,000 gal3,0355,015
1,500 gal3,0355,015
2,500 gal3,0355,015
5,000 gal3,0355,015

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