Hobart, WI rainwater: 25,124 gallons off a roof

How much rain a roof in Hobart, WI collects

25,124gallons a year

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

In Hobart, 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 Wfo station (2.2 mi away). Hobart, WI ranks 94th wettest of the 98 cities covered in Wisconsin.

Month by month in Hobart

Month	Rain (in)	Off the roof (gal)	Garden shortfall (gal)
Jan	1.38	1,097
Feb	1.20	954
Mar	1.96	1,558
Apr	3.00	2,384	168
May	3.48	2,766	108
Jun	4.11	3,267	30
Jul	3.62	2,877	91
Aug	3.34	2,655	126
Sep	3.16	2,512	148
Oct	2.65	2,106	212
Nov	1.97	1,566
Dec	1.74	1,383

Jun is the wettest month (4.11 in, 3,267 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.

Barrel or cistern in Hobart?

Best fit: one 55-gallon barrel, which delivers about 690 gallons to the garden in a normal year (78.1% 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 Hobart's roof water will pass straight through it.

Tank	Water used (gal/yr)	Spills over (gal/yr)
55 gal	690	23,369
110 gal	690	23,369
165 gal	690	23,369
275 gal	690	23,369
550 gal	690	23,369
1,000 gal	690	23,369
1,500 gal	690	23,369
2,500 gal	690	23,369
5,000 gal	690	23,369

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