RoofRainYield

Foley, AL rainwater: 56,972 gallons off a roof

How much rain a roof in Foley, AL collects

56,972gallons a year

That is a 1,500 sq ft asphalt roof under Foley, AL's normal 71.7 inches of rain, about 795 gallons for every inch that falls.

In Foley, 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 Foley 0.5 Ese station (0.6 mi away). Foley, AL ranks 1st wettest of the 66 cities covered in Alabama.

Month by month in Foley

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan5.434,316
Feb4.753,775
Mar5.604,451
Apr6.044,801
May5.124,069
Jun6.715,333
Jul8.877,050
Aug8.016,366
Sep6.325,023
Oct4.323,4344
Nov5.304,212
Dec5.214,141

Jul is the wettest month (8.87 in, 7,050 gal off the roof); Oct the driest (4.32 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 Foley?

Best fit: one 55-gallon barrel, which delivers about 3 gallons to the garden in a normal year (80.2% 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 Foley's roof water will pass straight through it.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal355,798
110 gal355,798
165 gal355,798
275 gal355,798
550 gal355,798
1,000 gal355,798
1,500 gal355,798
2,500 gal355,798
5,000 gal355,798

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