Lima, OH rainwater: 32,714 gallons off a roof
How much rain a roof in Lima, OH collects
32,714gallons a year
That is a 1,500 sq ft asphalt roof under Lima, OH's normal 41.2 inches of rain, about 795 gallons for every inch that falls.
In Lima, 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 Lima Wwtp station (1.4 mi away). Lima, OH ranks 120th wettest of the 176 cities covered in Ohio.
Month by month in Lima
| Month | Rain (in) | Off the roof (gal) | Garden shortfall (gal) |
|---|---|---|---|
| Jan | 2.83 | 2,249 | |
| Feb | 2.52 | 2,003 | |
| Mar | 3.02 | 2,400 | |
| Apr | 3.97 | 3,155 | 47 |
| May | 4.38 | 3,481 | |
| Jun | 4.29 | 3,410 | 7 |
| Jul | 4.37 | 3,473 | |
| Aug | 3.80 | 3,020 | 69 |
| Sep | 3.19 | 2,535 | 145 |
| Oct | 2.93 | 2,329 | 177 |
| Nov | 3.14 | 2,496 | |
| Dec | 2.72 | 2,162 |
May is the wettest month (4.38 in, 3,481 gal off the roof); Feb the driest (2.52 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 Lima
Best fit: one 55-gallon barrel, which delivers about 354 gallons to the garden in a normal year (79.5% 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 Lima's roof water will pass straight through it.
| Tank | Water used (gal/yr) | Spills over (gal/yr) |
|---|---|---|
| 55 gal | 354 | 31,130 |
| 110 gal | 354 | 31,130 |
| 165 gal | 354 | 31,130 |
| 275 gal | 354 | 31,130 |
| 550 gal | 354 | 31,130 |
| 1,000 gal | 354 | 31,130 |
| 1,500 gal | 354 | 31,130 |
| 2,500 gal | 354 | 31,130 |
| 5,000 gal | 354 | 31,130 |
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