RoofRainYield

Indian Trail, NC rainwater: 30,139 gallons off a roof

How much rain a roof in Indian Trail, NC collects

30,139gallons a year

That is a 1,500 sq ft asphalt roof under Indian Trail, NC's normal 37.9 inches of rain, about 795 gallons for every inch that falls.

In Indian Trail, 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 Monroe Ap station (4.0 mi away). Indian Trail, NC ranks 89th wettest of the 91 cities covered in North Carolina.

Month by month in Indian Trail

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan3.002,384
Feb2.772,202
Mar3.192,535
Apr2.902,305181
May2.892,297182
Jun3.732,96577
Jul3.632,88590
Aug3.793,01270
Sep3.182,527146
Oct2.972,361172
Nov2.912,313
Dec2.962,353

Aug is the wettest month (3.79 in, 3,012 gal off the roof); Feb the driest (2.77 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 Indian Trail?

Best fit: one 55-gallon barrel, which delivers about 759 gallons to the garden in a normal year (82.7% 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 Indian Trail's roof water will pass straight through it.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal75928,405
110 gal75928,405
165 gal75928,405
275 gal75928,405
550 gal75928,405
1,000 gal75928,405
1,500 gal75928,405
2,500 gal75928,405
5,000 gal75928,405

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