Fort Oglethorpe, GA rainwater: 44,875 gallons off a roof
Fort Oglethorpe, GA: gallons off the roof each year
44,875gallons a year
That is a 1,500 sq ft asphalt roof under Fort Oglethorpe, GA's normal 56.5 inches of rain, about 795 gallons for every inch that falls.
In Fort Oglethorpe, 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 Chickamauga Pk Larc station (1.6 mi away). Fort Oglethorpe, GA ranks 6th wettest of the 101 cities covered in Georgia.
Month by month in Fort Oglethorpe
| Month | Rain (in) | Off the roof (gal) | Garden shortfall (gal) |
|---|---|---|---|
| Jan | 5.61 | 4,459 | |
| Feb | 5.12 | 4,069 | |
| Mar | 5.03 | 3,998 | |
| Apr | 4.73 | 3,759 | |
| May | 4.64 | 3,688 | |
| Jun | 4.19 | 3,330 | 20 |
| Jul | 5.06 | 4,022 | |
| Aug | 4.47 | 3,553 | |
| Sep | 4.22 | 3,354 | 16 |
| Oct | 3.65 | 2,901 | 87 |
| Nov | 4.38 | 3,481 | |
| Dec | 5.36 | 4,260 |
Jan is the wettest month (5.61 in, 4,459 gal off the roof); Oct the driest (3.65 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 Fort Oglethorpe
Best fit: one 55-gallon barrel, which delivers about 105 gallons to the garden in a normal year (85.1% 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 Fort Oglethorpe's roof water will pass straight through it.
| Tank | Water used (gal/yr) | Spills over (gal/yr) |
|---|---|---|
| 55 gal | 105 | 43,569 |
| 110 gal | 105 | 43,569 |
| 165 gal | 105 | 43,569 |
| 275 gal | 105 | 43,569 |
| 550 gal | 105 | 43,569 |
| 1,000 gal | 105 | 43,569 |
| 1,500 gal | 105 | 43,569 |
| 2,500 gal | 105 | 43,569 |
| 5,000 gal | 105 | 43,569 |
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