RoofRainYield

Dumont, NJ rainwater: 37,443 gallons off a roof

Dumont, NJ: gallons off the roof each year

37,443gallons a year

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

In Dumont, NJ 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 New Milford station (1.6 mi away). Dumont, NJ ranks 92nd wettest of the 116 cities covered in New Jersey.

Month by month in Dumont

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan3.352,663
Feb3.022,400
Mar4.093,251
Apr3.863,06861
May3.562,83098
Jun4.073,23535
Jul4.493,569
Aug4.533,600
Sep4.533,600
Oct4.073,23535
Nov3.512,790
Dec4.033,203

Aug is the wettest month (4.53 in, 3,600 gal off the roof); Feb the driest (3.02 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 Dumont

Best fit: one 55-gallon barrel, which delivers about 182 gallons to the garden in a normal year (79.3% 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 Dumont's roof water will pass straight through it.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal18236,166
110 gal18236,166
165 gal18236,166
275 gal18236,166
550 gal18236,166
1,000 gal18236,166
1,500 gal18236,166
2,500 gal18236,166
5,000 gal18236,166

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 New Jersey?

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