Allouez, WI rainwater: 25,632 gallons off a roof

How much rain a roof in Allouez, WI collects

25,632gallons a year

That is a 1,500 sq ft asphalt roof under Allouez, WI's normal 32.3 inches of rain, about 795 gallons for every inch that falls.

In Allouez, 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 3.8 Sse station (2.6 mi away). Allouez, WI ranks 89th wettest of the 98 cities covered in Wisconsin.

Month by month in Allouez

Month	Rain (in)	Off the roof (gal)	Garden shortfall (gal)
Jan	1.44	1,145
Feb	1.23	978
Mar	1.90	1,510
Apr	3.12	2,480	153
May	3.50	2,782	106
Jun	4.11	3,267	30
Jul	3.61	2,869	92
Aug	3.24	2,575	138
Sep	3.66	2,909	86
Oct	2.75	2,186	199
Nov	1.96	1,558
Dec	1.73	1,375

Jun is the wettest month (4.11 in, 3,267 gal off the roof); Feb the driest (1.23 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 Allouez?

Best fit: one 55-gallon barrel, which delivers about 634 gallons to the garden in a normal year (78.7% 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 Allouez's roof water will pass straight through it.

Tank	Water used (gal/yr)	Spills over (gal/yr)
55 gal	634	23,948
110 gal	634	23,948
165 gal	634	23,948
275 gal	634	23,948
550 gal	634	23,948
1,000 gal	634	23,948
1,500 gal	634	23,948
2,500 gal	634	23,948
5,000 gal	634	23,948

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