Trotwood, OH rainwater: 33,525 gallons off a roof
Rainwater from a roof in Trotwood, OH
33,525gallons a year
That is a 1,500 sq ft asphalt roof under Trotwood, OH's normal 42.2 inches of rain, about 795 gallons for every inch that falls.
In Trotwood, 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 New Lebanon 0.6 Sse station (5.4 mi away). Trotwood, OH ranks 81st wettest of the 176 cities covered in Ohio.
Month by month in Trotwood
| Month | Rain (in) | Off the roof (gal) | Garden shortfall (gal) |
|---|---|---|---|
| Jan | 3.14 | 2,496 | |
| Feb | 2.37 | 1,884 | |
| Mar | 3.52 | 2,798 | |
| Apr | 4.40 | 3,497 | |
| May | 4.44 | 3,529 | |
| Jun | 4.61 | 3,664 | |
| Jul | 3.93 | 3,124 | 52 |
| Aug | 3.10 | 2,464 | 156 |
| Sep | 3.20 | 2,543 | 143 |
| Oct | 3.32 | 2,639 | 128 |
| Nov | 3.04 | 2,416 | |
| Dec | 3.11 | 2,472 |
Jun is the wettest month (4.61 in, 3,664 gal off the roof); Feb the driest (2.37 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 Trotwood?
Best fit: one 55-gallon barrel, which delivers about 393 gallons to the garden in a normal year (81.9% 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 Trotwood's roof water will pass straight through it.
| Tank | Water used (gal/yr) | Spills over (gal/yr) |
|---|---|---|
| 55 gal | 393 | 31,931 |
| 110 gal | 393 | 31,931 |
| 165 gal | 393 | 31,931 |
| 275 gal | 393 | 31,931 |
| 550 gal | 393 | 31,931 |
| 1,000 gal | 393 | 31,931 |
| 1,500 gal | 393 | 31,931 |
| 2,500 gal | 393 | 31,931 |
| 5,000 gal | 393 | 31,931 |
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