RoofRainYield

Newton, NC rainwater: 37,054 gallons off a roof

How much rain a roof in Newton, NC collects

37,054gallons a year

That is a 1,500 sq ft asphalt roof under Newton, NC's normal 46.6 inches of rain, about 795 gallons for every inch that falls.

In Newton, NC 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 Catawba 5 Sw station (5.6 mi away). Newton, NC ranks 59th wettest of the 91 cities covered in North Carolina.

Month by month in Newton

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan3.722,957
Feb3.152,504
Mar4.243,370
Apr3.853,06062
May4.133,28327
Jun4.173,31422
Jul4.153,29825
Aug4.783,799
Sep4.013,18742
Oct3.332,647127
Nov3.472,758
Dec3.622,877

Aug is the wettest month (4.78 in, 3,799 gal off the roof); Feb the driest (3.15 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 Newton?

Best fit: one 55-gallon barrel, which delivers about 250 gallons to the garden in a normal year (81.5% 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 Newton's roof water will pass straight through it.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal25035,694
110 gal25035,694
165 gal25035,694
275 gal25035,694
550 gal25035,694
1,000 gal25035,694
1,500 gal25035,694
2,500 gal25035,694
5,000 gal25035,694

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 North Carolina?

Regulated through the Department of Environment and Natural Resources; allowed through state’s plumbing code; check county for local incentives

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