RoofRainYield

Suamico, WI rainwater: 25,744 gallons off a roof

Rainwater from a roof in Suamico, WI

25,744gallons a year

That is a 1,500 sq ft asphalt roof under Suamico, WI's normal 32.4 inches of rain, about 795 gallons for every inch that falls.

In Suamico, 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 Green Bay Botanical station (7.2 mi away). Suamico, WI ranks 85th wettest of the 98 cities covered in Wisconsin.

Month by month in Suamico

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan1.321,049
Feb1.10874
Mar1.871,486
Apr3.132,488152
May3.572,83797
Jun4.223,35416
Jul3.742,97376
Aug3.442,734113
Sep3.392,694120
Oct2.822,241191
Nov2.031,613
Dec1.761,399

Jun is the wettest month (4.22 in, 3,354 gal off the roof); Feb the driest (1.10 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 Suamico?

Best fit: one 55-gallon barrel, which delivers about 604 gallons to the garden in a normal year (78.9% 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 Suamico's roof water will pass straight through it.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal60424,090
110 gal60424,090
165 gal60424,090
275 gal60424,090
550 gal60424,090
1,000 gal60424,090
1,500 gal60424,090
2,500 gal60424,090
5,000 gal60424,090

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