RoofRainYield

Burlington, NC rainwater: 37,404 gallons off a roof

Rainwater from a roof in Burlington, NC

37,404gallons a year

That is a 1,500 sq ft asphalt roof under Burlington, NC's normal 47.1 inches of rain, about 795 gallons for every inch that falls.

In Burlington, 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 Burlington Fire Stn #5 station (1.6 mi away). Burlington, NC ranks 51st wettest of the 91 cities covered in North Carolina.

Month by month in Burlington

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan3.963,147
Feb3.242,575
Mar4.443,529
Apr3.833,04465
May3.632,88590
Jun4.633,680
Jul4.393,489
Aug4.123,27529
Sep4.913,902
Oct3.352,663125
Nov3.212,551
Dec3.352,663

Sep is the wettest month (4.91 in, 3,902 gal off the roof); Nov the driest (3.21 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 Burlington

Best fit: one 55-gallon barrel, which delivers about 253 gallons to the garden in a normal year (82.2% 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 Burlington's roof water will pass straight through it.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal25336,055
110 gal25336,055
165 gal25336,055
275 gal25336,055
550 gal25336,055
1,000 gal25336,055
1,500 gal25336,055
2,500 gal25336,055
5,000 gal25336,055

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