RoofRainYield

Elizabeth City, NC rainwater: 40,742 gallons off a roof

Elizabeth City, NC: gallons off the roof each year

40,742gallons a year

That is a 1,500 sq ft asphalt roof under Elizabeth City, NC's normal 51.3 inches of rain, about 795 gallons for every inch that falls.

In Elizabeth City, 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 Elizabeth City station (2.1 mi away). Elizabeth City, NC ranks 14th wettest of the 91 cities covered in North Carolina.

Month by month in Elizabeth City

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan3.642,893
Feb3.292,615
Mar4.173,314
Apr3.472,758110
May4.073,23535
Jun4.493,569
Jul5.934,713
Aug5.914,697
Sep5.324,228
Oct3.702,94181
Nov3.392,694
Dec3.883,084

Jul is the wettest month (5.93 in, 4,713 gal off the roof); Feb the driest (3.29 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 Elizabeth City

Best fit: one 55-gallon barrel, which delivers about 183 gallons to the garden in a normal year (81.1% 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 Elizabeth City's roof water will pass straight through it.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal18339,344
110 gal18339,344
165 gal18339,344
275 gal18339,344
550 gal18339,344
1,000 gal18339,344
1,500 gal18339,344
2,500 gal18339,344
5,000 gal18339,344

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