RoofRainYield

Flowery Branch, GA rainwater: 45,606 gallons off a roof

How much rain a roof in Flowery Branch, GA collects

45,606gallons a year

That is a 1,500 sq ft asphalt roof under Flowery Branch, GA's normal 57.4 inches of rain, about 795 gallons for every inch that falls.

In Flowery Branch, 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 Flowery Branch 1.1 Ssw station (0.4 mi away). Flowery Branch, GA ranks 3rd wettest of the 101 cities covered in Georgia.

Month by month in Flowery Branch

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan5.274,189
Feb5.174,109
Mar5.154,093
Apr4.383,481
May4.623,672
Jun5.013,982
Jul4.823,831
Aug4.833,839
Sep4.393,489
Oct4.083,24334
Nov4.403,497
Dec5.264,181

Jan is the wettest month (5.27 in, 4,189 gal off the roof); Oct the driest (4.08 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 Flowery Branch

Best fit: one 55-gallon barrel, which delivers about 28 gallons to the garden in a normal year (83.2% 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 Flowery Branch's roof water will pass straight through it.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal2844,363
110 gal2844,363
165 gal2844,363
275 gal2844,363
550 gal2844,363
1,000 gal2844,363
1,500 gal2844,363
2,500 gal2844,363
5,000 gal2844,363

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