Amherst, OH rainwater: 29,185 gallons off a roof
Rainwater from a roof in Amherst, OH
29,185gallons a year
That is a 1,500 sq ft asphalt roof under Amherst, OH's normal 36.7 inches of rain, about 795 gallons for every inch that falls.
In Amherst, 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 Elyria Lorain Co Ap station (4.9 mi away). Amherst, OH ranks 160th wettest of the 176 cities covered in Ohio.
Month by month in Amherst
| Month | Rain (in) | Off the roof (gal) | Garden shortfall (gal) |
|---|---|---|---|
| Jan | 2.11 | 1,677 | |
| Feb | 1.66 | 1,319 | |
| Mar | 2.48 | 1,971 | |
| Apr | 3.28 | 2,607 | 133 |
| May | 3.64 | 2,893 | 89 |
| Jun | 3.87 | 3,076 | 60 |
| Jul | 3.56 | 2,830 | 98 |
| Aug | 3.63 | 2,885 | 90 |
| Sep | 3.74 | 2,973 | 76 |
| Oct | 3.50 | 2,782 | 106 |
| Nov | 2.96 | 2,353 | |
| Dec | 2.29 | 1,820 |
Jun is the wettest month (3.87 in, 3,076 gal off the roof); Feb the driest (1.66 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 Amherst?
Best fit: one 55-gallon barrel, which delivers about 505 gallons to the garden in a normal year (77.4% 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 Amherst's roof water will pass straight through it.
| Tank | Water used (gal/yr) | Spills over (gal/yr) |
|---|---|---|
| 55 gal | 505 | 27,540 |
| 110 gal | 505 | 27,540 |
| 165 gal | 505 | 27,540 |
| 275 gal | 505 | 27,540 |
| 550 gal | 505 | 27,540 |
| 1,000 gal | 505 | 27,540 |
| 1,500 gal | 505 | 27,540 |
| 2,500 gal | 505 | 27,540 |
| 5,000 gal | 505 | 27,540 |
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