Macon-Bibb County, GA rainwater: 40,766 gallons off a roof
Macon-Bibb County, GA: gallons off the roof each year
40,766gallons a year
That is a 1,500 sq ft asphalt roof under Macon-Bibb County, GA's normal 51.3 inches of rain, about 795 gallons for every inch that falls.
In Macon-Bibb County, 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 Macon 6.3 E station (8.7 mi away). Macon-Bibb County, GA ranks 66th wettest of the 101 cities covered in Georgia.
Month by month in Macon-Bibb County
| Month | Rain (in) | Off the roof (gal) | Garden shortfall (gal) |
|---|---|---|---|
| Jan | 4.49 | 3,569 | |
| Feb | 4.41 | 3,505 | |
| Mar | 4.72 | 3,751 | |
| Apr | 4.18 | 3,322 | 21 |
| May | 3.31 | 2,631 | 130 |
| Jun | 4.99 | 3,966 | |
| Jul | 4.93 | 3,918 | |
| Aug | 4.55 | 3,616 | |
| Sep | 4.02 | 3,195 | 41 |
| Oct | 3.11 | 2,472 | 155 |
| Nov | 3.48 | 2,766 | |
| Dec | 5.10 | 4,054 |
Dec is the wettest month (5.10 in, 4,054 gal off the roof); Oct the driest (3.11 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 Macon-Bibb County
Best fit: one 55-gallon barrel, which delivers about 296 gallons to the garden in a normal year (85.4% 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 Macon-Bibb County's roof water will pass straight through it.
| Tank | Water used (gal/yr) | Spills over (gal/yr) |
|---|---|---|
| 55 gal | 296 | 39,420 |
| 110 gal | 296 | 39,420 |
| 165 gal | 296 | 39,420 |
| 275 gal | 296 | 39,420 |
| 550 gal | 296 | 39,420 |
| 1,000 gal | 296 | 39,420 |
| 1,500 gal | 296 | 39,420 |
| 2,500 gal | 296 | 39,420 |
| 5,000 gal | 296 | 39,420 |
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