Carrollton, GA rainwater: 42,506 gallons off a roof
Carrollton, GA: gallons off the roof each year
42,506gallons a year
That is a 1,500 sq ft asphalt roof under Carrollton, GA's normal 53.5 inches of rain, about 795 gallons for every inch that falls.
In Carrollton, GA 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 Carrollton station (1.1 mi away). Carrollton, GA ranks 43rd wettest of the 101 cities covered in Georgia.
Month by month in Carrollton
| Month | Rain (in) | Off the roof (gal) | Garden shortfall (gal) |
|---|---|---|---|
| Jan | 5.00 | 3,974 | |
| Feb | 5.30 | 4,212 | |
| Mar | 5.59 | 4,443 | |
| Apr | 4.59 | 3,648 | |
| May | 3.77 | 2,996 | 72 |
| Jun | 4.13 | 3,283 | 27 |
| Jul | 4.45 | 3,537 | |
| Aug | 3.68 | 2,925 | 84 |
| Sep | 3.83 | 3,044 | 65 |
| Oct | 3.66 | 2,909 | 86 |
| Nov | 4.39 | 3,489 | |
| Dec | 5.09 | 4,046 |
Mar is the wettest month (5.59 in, 4,443 gal off the roof); Oct the driest (3.66 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 Carrollton
Best fit: one 55-gallon barrel, which delivers about 269 gallons to the garden in a normal year (80.5% 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 Carrollton's roof water will pass straight through it.
| Tank | Water used (gal/yr) | Spills over (gal/yr) |
|---|---|---|
| 55 gal | 269 | 41,007 |
| 110 gal | 269 | 41,007 |
| 165 gal | 269 | 41,007 |
| 275 gal | 269 | 41,007 |
| 550 gal | 269 | 41,007 |
| 1,000 gal | 269 | 41,007 |
| 1,500 gal | 269 | 41,007 |
| 2,500 gal | 269 | 41,007 |
| 5,000 gal | 269 | 41,007 |
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 Georgia?
Legal. Outdoor irrigation use is unrestricted; indoor non-potable systems must follow Appendix I 'Rainwater Recycling Systems' of the Georgia amendments to the state plumbing code. No state storage cap; potable use depends on local rules.
Checked against the current source on 2026-11-06. Source