RoofRainYield

Fort Payne, AL rainwater: 47,323 gallons off a roof

Rainwater from a roof in Fort Payne, AL

47,323gallons a year

That is a 1,500 sq ft asphalt roof under Fort Payne, AL's normal 59.5 inches of rain, about 795 gallons for every inch that falls.

In Fort Payne, 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 Fort Payne 1.4 Wsw station (1.8 mi away). Fort Payne, AL ranks 15th wettest of the 66 cities covered in Alabama.

Month by month in Fort Payne

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan5.544,403
Feb5.524,387
Mar5.814,618
Apr5.684,514
May4.813,823
Jun4.363,465
Jul4.523,593
Aug4.073,23535
Sep4.963,942
Oct3.452,742112
Nov4.733,759
Dec6.094,840

Dec is the wettest month (6.09 in, 4,840 gal off the roof); Oct the driest (3.45 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 Fort Payne?

Best fit: one 55-gallon barrel, which delivers about 116 gallons to the garden in a normal year (78.8% 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 Fort Payne's roof water will pass straight through it.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal11645,886
110 gal11645,886
165 gal11645,886
275 gal11645,886
550 gal11645,886
1,000 gal11645,886
1,500 gal11645,886
2,500 gal11645,886
5,000 gal11645,886

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