Brookhaven, GA rainwater: 40,877 gallons off a roof
Brookhaven, GA: gallons off the roof each year
40,877gallons a year
That is a 1,500 sq ft asphalt roof under Brookhaven, GA's normal 51.4 inches of rain, about 795 gallons for every inch that falls.
In Brookhaven, 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 Atlanta Peachtree Ap station (2.2 mi away). Brookhaven, GA ranks 64th wettest of the 101 cities covered in Georgia.
Month by month in Brookhaven
| Month | Rain (in) | Off the roof (gal) | Garden shortfall (gal) |
|---|---|---|---|
| Jan | 4.57 | 3,632 | |
| Feb | 4.47 | 3,553 | |
| Mar | 4.70 | 3,736 | |
| Apr | 3.87 | 3,076 | 60 |
| May | 3.83 | 3,044 | 65 |
| Jun | 4.69 | 3,728 | |
| Jul | 4.71 | 3,744 | |
| Aug | 4.51 | 3,585 | |
| Sep | 4.12 | 3,275 | 29 |
| Oct | 3.39 | 2,694 | 120 |
| Nov | 4.21 | 3,346 | |
| Dec | 4.36 | 3,465 |
Jul is the wettest month (4.71 in, 3,744 gal off the roof); Oct the driest (3.39 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 Brookhaven
Best fit: one 55-gallon barrel, which delivers about 224 gallons to the garden in a normal year (82.0% 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 Brookhaven's roof water will pass straight through it.
| Tank | Water used (gal/yr) | Spills over (gal/yr) |
|---|---|---|
| 55 gal | 224 | 39,483 |
| 110 gal | 224 | 39,483 |
| 165 gal | 224 | 39,483 |
| 275 gal | 224 | 39,483 |
| 550 gal | 224 | 39,483 |
| 1,000 gal | 224 | 39,483 |
| 1,500 gal | 224 | 39,483 |
| 2,500 gal | 224 | 39,483 |
| 5,000 gal | 224 | 39,483 |
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