Washington Court House, OH rainwater: 32,420 gallons off a roof
How much rain a roof in Washington Court House, OH collects
32,420gallons a year
That is a 1,500 sq ft asphalt roof under Washington Court House, OH's normal 40.8 inches of rain, about 795 gallons for every inch that falls.
In Washington Court House, 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 Washington Court House station (0.3 mi away). Washington Court House, OH ranks 133rd wettest of the 176 cities covered in Ohio.
Month by month in Washington Court House
| Month | Rain (in) | Off the roof (gal) | Garden shortfall (gal) |
|---|---|---|---|
| Jan | 3.01 | 2,392 | |
| Feb | 2.53 | 2,011 | |
| Mar | 3.76 | 2,988 | |
| Apr | 4.06 | 3,227 | 36 |
| May | 4.45 | 3,537 | |
| Jun | 4.33 | 3,442 | 2 |
| Jul | 3.95 | 3,139 | 50 |
| Aug | 3.35 | 2,663 | 125 |
| Sep | 2.69 | 2,138 | 207 |
| Oct | 2.69 | 2,138 | 207 |
| Nov | 2.78 | 2,210 | |
| Dec | 3.19 | 2,535 |
May is the wettest month (4.45 in, 3,537 gal off the roof); Feb the driest (2.53 in). Garden shortfall is what a 200 sq ft vegetable bed needs beyond the rain that lands on it, April to October.
Which tank size is worth it in Washington Court House
Best fit: one 55-gallon barrel, which delivers about 510 gallons to the garden in a normal year (81.3% of its need).
If you set one up, a 55-gallon barrel with a downspout diverter is the whole job. Check that the overflow points away from your foundation, because most of Washington Court House's roof water will pass straight through it.
| Tank | Water used (gal/yr) | Spills over (gal/yr) |
|---|---|---|
| 55 gal | 510 | 30,680 |
| 110 gal | 510 | 30,680 |
| 165 gal | 510 | 30,680 |
| 275 gal | 510 | 30,680 |
| 550 gal | 510 | 30,680 |
| 1,000 gal | 510 | 30,680 |
| 1,500 gal | 510 | 30,680 |
| 2,500 gal | 510 | 30,680 |
| 5,000 gal | 510 | 30,680 |
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