Cambridge, OH rainwater: 32,841 gallons off a roof
Cambridge, OH: gallons off the roof each year
32,841gallons a year
That is a 1,500 sq ft asphalt roof under Cambridge, OH's normal 41.3 inches of rain, about 795 gallons for every inch that falls.
In Cambridge, 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 Cambridge station (0.8 mi away). Cambridge, OH ranks 119th wettest of the 176 cities covered in Ohio.
Month by month in Cambridge
| Month | Rain (in) | Off the roof (gal) | Garden shortfall (gal) |
|---|---|---|---|
| Jan | 3.25 | 2,583 | |
| Feb | 2.41 | 1,915 | |
| Mar | 3.27 | 2,599 | |
| Apr | 3.84 | 3,052 | 64 |
| May | 4.23 | 3,362 | 15 |
| Jun | 4.46 | 3,545 | |
| Jul | 4.04 | 3,211 | 39 |
| Aug | 3.49 | 2,774 | 107 |
| Sep | 3.47 | 2,758 | 110 |
| Oct | 2.87 | 2,281 | 185 |
| Nov | 3.00 | 2,384 | |
| Dec | 2.99 | 2,376 |
Jun is the wettest month (4.46 in, 3,545 gal off the roof); Feb the driest (2.41 in). Garden shortfall is what a 200 sq ft vegetable bed needs beyond the rain that lands on it, April to October.
What size rain barrel for Cambridge
Best fit: one 55-gallon barrel, which delivers about 409 gallons to the garden in a normal year (78.9% 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 Cambridge's roof water will pass straight through it.
| Tank | Water used (gal/yr) | Spills over (gal/yr) |
|---|---|---|
| 55 gal | 409 | 31,157 |
| 110 gal | 409 | 31,157 |
| 165 gal | 409 | 31,157 |
| 275 gal | 409 | 31,157 |
| 550 gal | 409 | 31,157 |
| 1,000 gal | 409 | 31,157 |
| 1,500 gal | 409 | 31,157 |
| 2,500 gal | 409 | 31,157 |
| 5,000 gal | 409 | 31,157 |
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