RoofRainYield

Oxford, AL rainwater: 41,425 gallons off a roof

Oxford, AL: gallons off the roof each year

41,425gallons a year

That is a 1,500 sq ft asphalt roof under Oxford, AL's normal 52.1 inches of rain, about 795 gallons for every inch that falls.

In Oxford, 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 Anniston Metro Ap station (1.0 mi away). Oxford, AL ranks 64th wettest of the 66 cities covered in Alabama.

Month by month in Oxford

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan4.843,847
Feb5.084,038
Mar5.374,268
Apr4.433,521
May4.353,457
Jun4.373,473
Jul4.683,720
Aug3.512,790105
Sep3.112,472155
Oct3.252,583137
Nov4.533,600
Dec4.603,656

Mar is the wettest month (5.37 in, 4,268 gal off the roof); Sep the driest (3.11 in). Garden shortfall is what a 200 sq ft vegetable bed needs beyond the rain that lands on it, April to October.

What size rain barrel for Oxford

Best fit: one 55-gallon barrel, which delivers about 333 gallons to the garden in a normal year (84.0% 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 Oxford's roof water will pass straight through it.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal33339,892
110 gal33339,892
165 gal33339,892
275 gal33339,892
550 gal33339,892
1,000 gal33339,892
1,500 gal33339,892
2,500 gal33339,892
5,000 gal33339,892

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