Duluth, GA rainwater: 43,023 gallons off a roof
Rainwater from a roof in Duluth, GA
43,023gallons a year
That is a 1,500 sq ft asphalt roof under Duluth, GA's normal 54.1 inches of rain, about 795 gallons for every inch that falls.
In Duluth, 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 Duluth 0.9 Ene station (0.9 mi away). Duluth, GA ranks 28th wettest of the 101 cities covered in Georgia.
Month by month in Duluth
| Month | Rain (in) | Off the roof (gal) | Garden shortfall (gal) |
|---|---|---|---|
| Jan | 4.93 | 3,918 | |
| Feb | 4.74 | 3,767 | |
| Mar | 4.92 | 3,910 | |
| Apr | 4.08 | 3,243 | 34 |
| May | 4.24 | 3,370 | 14 |
| Jun | 4.76 | 3,783 | |
| Jul | 5.16 | 4,101 | |
| Aug | 4.36 | 3,465 | |
| Sep | 4.24 | 3,370 | 14 |
| Oct | 3.82 | 3,036 | 66 |
| Nov | 4.23 | 3,362 | |
| Dec | 4.65 | 3,696 |
Jul is the wettest month (5.16 in, 4,101 gal off the roof); Oct the driest (3.82 in). Garden shortfall is what a 200 sq ft vegetable bed needs beyond the rain that lands on it, April to October.
Barrel or cistern in Duluth?
Best fit: one 55-gallon barrel, which delivers about 106 gallons to the garden in a normal year (83.4% 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 Duluth's roof water will pass straight through it.
| Tank | Water used (gal/yr) | Spills over (gal/yr) |
|---|---|---|
| 55 gal | 106 | 41,687 |
| 110 gal | 106 | 41,687 |
| 165 gal | 106 | 41,687 |
| 275 gal | 106 | 41,687 |
| 550 gal | 106 | 41,687 |
| 1,000 gal | 106 | 41,687 |
| 1,500 gal | 106 | 41,687 |
| 2,500 gal | 106 | 41,687 |
| 5,000 gal | 106 | 41,687 |
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