RoofRainYield

Waupun, WI rainwater: 30,052 gallons off a roof

Waupun, WI: gallons off the roof each year

30,052gallons a year

That is a 1,500 sq ft asphalt roof under Waupun, WI's normal 37.8 inches of rain, about 795 gallons for every inch that falls.

In Waupun, WI 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 Town Of Westford station (13.2 mi away). Waupun, WI ranks 12th wettest of the 98 cities covered in Wisconsin.

Month by month in Waupun

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan1.641,303
Feb1.681,335
Mar2.431,931
Apr3.772,99672
May4.423,513
Jun5.003,974
Jul4.143,29026
Aug3.752,98175
Sep3.572,83797
Oct3.122,480153
Nov2.341,860
Dec1.951,550

Jun is the wettest month (5.00 in, 3,974 gal off the roof); Jan the driest (1.64 in). Garden shortfall is what a 200 sq ft vegetable bed needs beyond the rain that lands on it, April to October.

Which tank size is worth it in Waupun

Best fit: one 55-gallon barrel, which delivers about 331 gallons to the garden in a normal year (78.1% 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 Waupun's roof water will pass straight through it.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal33128,581
110 gal33128,581
165 gal33128,581
275 gal33128,581
550 gal33128,581
1,000 gal33128,581
1,500 gal33128,581
2,500 gal33128,581
5,000 gal33128,581

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 Wisconsin?

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