Blue Ash, OH rainwater: 34,495 gallons off a roof
How much rain a roof in Blue Ash, OH collects
34,495gallons a year
That is a 1,500 sq ft asphalt roof under Blue Ash, OH's normal 43.4 inches of rain, about 795 gallons for every inch that falls.
In Blue Ash, 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 Cincinnati Lunken Ap station (10.0 mi away). Blue Ash, OH ranks 48th wettest of the 176 cities covered in Ohio.
Month by month in Blue Ash
| Month | Rain (in) | Off the roof (gal) | Garden shortfall (gal) |
|---|---|---|---|
| Jan | 2.86 | 2,273 | |
| Feb | 2.79 | 2,218 | |
| Mar | 3.94 | 3,132 | |
| Apr | 4.37 | 3,473 | |
| May | 4.70 | 3,736 | |
| Jun | 4.61 | 3,664 | |
| Jul | 4.39 | 3,489 | |
| Aug | 3.39 | 2,694 | 120 |
| Sep | 3.07 | 2,440 | 160 |
| Oct | 3.05 | 2,424 | 162 |
| Nov | 2.91 | 2,313 | |
| Dec | 3.32 | 2,639 |
May is the wettest month (4.70 in, 3,736 gal off the roof); Feb the driest (2.79 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 Blue Ash
Best fit: one 55-gallon barrel, which delivers about 360 gallons to the garden in a normal year (81.6% of its need).
If you buy one, a 55-gallon barrel with a downspout diverter is the whole job. Check that the overflow points away from your foundation, because most of Blue Ash's roof water will pass straight through it.
| Tank | Water used (gal/yr) | Spills over (gal/yr) |
|---|---|---|
| 55 gal | 360 | 32,919 |
| 110 gal | 360 | 32,919 |
| 165 gal | 360 | 32,919 |
| 275 gal | 360 | 32,919 |
| 550 gal | 360 | 32,919 |
| 1,000 gal | 360 | 32,919 |
| 1,500 gal | 360 | 32,919 |
| 2,500 gal | 360 | 32,919 |
| 5,000 gal | 360 | 32,919 |
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