RoofRainYield

Avon, OH rainwater: 33,732 gallons off a roof

Rainwater from a roof in Avon, OH

33,732gallons a year

That is a 1,500 sq ft asphalt roof under Avon, OH's normal 42.4 inches of rain, about 795 gallons for every inch that falls.

In Avon, OH a single barrel does most of the work. Storms come often enough that a small tank refills before it runs dry, and a bigger one would mostly sit full.

Rainfall: NOAA 1991-2020 climate normals, the Westlake 0.5 Ssw station (3.8 mi away). Avon, OH ranks 72nd wettest of the 176 cities covered in Ohio.

Month by month in Avon

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan3.152,504
Feb2.221,764
Mar3.012,392
Apr3.863,06861
May4.363,465
Jun3.783,00471
Jul4.083,24334
Aug4.033,20340
Sep3.632,88590
Oct3.652,90187
Nov3.452,742
Dec3.222,559

May is the wettest month (4.36 in, 3,465 gal off the roof); Feb the driest (2.22 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 Avon

Best fit: one 55-gallon barrel, which delivers about 293 gallons to the garden in a normal year (76.6% of its need).

If you buy one, a 55-gallon barrel with a downspout diverter is the whole job. Check that the overflow points away from your foundation, because most of Avon's roof water will pass straight through it.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal29332,104
110 gal29332,104
165 gal29332,104
275 gal29332,104
550 gal29332,104
1,000 gal29332,104
1,500 gal29332,104
2,500 gal29332,104
5,000 gal29332,104

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 Ohio?

Legal. Ohio regulates rainwater cisterns used as a drinking-water source as private water systems (OAC chapter 3701-28): local health department permit, continuous disinfection and filtration. No state rule restricting non-potable collection or storage size.

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