RoofRainYield

De Pere, WI rainwater: 25,124 gallons off a roof

De Pere, WI: gallons off the roof each year

25,124gallons a year

That is a 1,500 sq ft asphalt roof under De Pere, WI's normal 31.6 inches of rain, about 795 gallons for every inch that falls.

In De Pere, 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 station (4.9 mi away). De Pere, WI ranks 92nd wettest of the 98 cities covered in Wisconsin.

Month by month in De Pere

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan1.391,105
Feb1.20954
Mar1.961,558
Apr3.002,384168
May3.352,663125
Jun4.103,25931
Jul3.622,87791
Aug3.392,694120
Sep3.202,543143
Oct2.672,122209
Nov1.981,574
Dec1.751,391

Jun is the wettest month (4.10 in, 3,259 gal off the roof); Feb the driest (1.20 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 De Pere

Best fit: one 55-gallon barrel, which delivers about 699 gallons to the garden in a normal year (78.7% of its need).

If you buy one, a 55-gallon barrel with a downspout diverter is the whole job. Check that the overflow points away from your foundation, because most of De Pere's roof water will pass straight through it.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal69923,375
110 gal69923,375
165 gal69923,375
275 gal69923,375
550 gal69923,375
1,000 gal69923,375
1,500 gal69923,375
2,500 gal69923,375
5,000 gal69923,375

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