Piqua, OH rainwater: 34,463 gallons off a roof
How much rain a roof in Piqua, OH collects
34,463gallons a year
That is a 1,500 sq ft asphalt roof under Piqua, OH's normal 43.4 inches of rain, about 795 gallons for every inch that falls.
In Piqua, 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 Piqua station (0.5 mi away). Piqua, OH ranks 49th wettest of the 176 cities covered in Ohio.
Month by month in Piqua
| Month | Rain (in) | Off the roof (gal) | Garden shortfall (gal) |
|---|---|---|---|
| Jan | 3.38 | 2,686 | |
| Feb | 2.49 | 1,979 | |
| Mar | 3.21 | 2,551 | |
| Apr | 4.16 | 3,306 | 24 |
| May | 4.33 | 3,442 | 2 |
| Jun | 4.61 | 3,664 | |
| Jul | 4.71 | 3,744 | |
| Aug | 3.93 | 3,124 | 52 |
| Sep | 3.14 | 2,496 | 151 |
| Oct | 2.96 | 2,353 | 173 |
| Nov | 3.28 | 2,607 | |
| Dec | 3.16 | 2,512 |
Jul is the wettest month (4.71 in, 3,744 gal off the roof); Feb the driest (2.49 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 Piqua?
Best fit: one 55-gallon barrel, which delivers about 322 gallons to the garden in a normal year (80.0% of its need).
Before you buy, a 55-gallon barrel with a downspout diverter is the whole job. Check that the overflow points away from your foundation, because most of Piqua's roof water will pass straight through it.
| Tank | Water used (gal/yr) | Spills over (gal/yr) |
|---|---|---|
| 55 gal | 322 | 32,926 |
| 110 gal | 322 | 32,926 |
| 165 gal | 322 | 32,926 |
| 275 gal | 322 | 32,926 |
| 550 gal | 322 | 32,926 |
| 1,000 gal | 322 | 32,926 |
| 1,500 gal | 322 | 32,926 |
| 2,500 gal | 322 | 32,926 |
| 5,000 gal | 322 | 32,926 |
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