RoofRainYield

Jacksonville, AL rainwater: 42,673 gallons off a roof

How much rain a roof in Jacksonville, AL collects

42,673gallons a year

That is a 1,500 sq ft asphalt roof under Jacksonville, AL's normal 53.7 inches of rain, about 795 gallons for every inch that falls.

In Jacksonville, AL 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 Jacksonville station (1.8 mi away). Jacksonville, AL ranks 60th wettest of the 66 cities covered in Alabama.

Month by month in Jacksonville

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan4.933,918
Feb5.104,054
Mar5.474,348
Apr4.773,791
May4.423,513
Jun4.593,648
Jul4.523,593
Aug3.752,98175
Sep3.823,03666
Oct3.312,631130
Nov4.283,402
Dec4.733,759

Mar is the wettest month (5.47 in, 4,348 gal off the roof); Oct the driest (3.31 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 Jacksonville

Best fit: one 55-gallon barrel, which delivers about 228 gallons to the garden in a normal year (84.3% 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 Jacksonville's roof water will pass straight through it.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal22841,260
110 gal22841,260
165 gal22841,260
275 gal22841,260
550 gal22841,260
1,000 gal22841,260
1,500 gal22841,260
2,500 gal22841,260
5,000 gal22841,260

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 Alabama?

No rainwater harvesting regulations

From the 2015 (Pacific Northwest National Laboratory report 24347); not yet re-checked against current law, so check with your state water agency before building anything large. Source