RoofRainYield

Verona, WI rainwater: 32,031 gallons off a roof

How much rain a roof in Verona, WI collects

32,031gallons a year

That is a 1,500 sq ft asphalt roof under Verona, WI's normal 40.3 inches of rain, about 795 gallons for every inch that falls.

In Verona, 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 Madison 5.0 Sw station (4.0 mi away). Verona, WI ranks 1st wettest of the 98 cities covered in Wisconsin.

Month by month in Verona

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan1.641,303
Feb1.681,335
Mar2.241,780
Apr4.023,19541
May4.483,561
Jun6.234,952
Jul4.833,839
Aug4.313,4265
Sep3.662,90986
Oct3.042,416163
Nov2.341,860
Dec1.831,454

Jun is the wettest month (6.23 in, 4,952 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.

Barrel or cistern in Verona?

Best fit: one 55-gallon barrel, which delivers about 236 gallons to the garden in a normal year (79.9% 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 Verona's roof water will pass straight through it.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal23630,700
110 gal23630,700
165 gal23630,700
275 gal23630,700
550 gal23630,700
1,000 gal23630,700
1,500 gal23630,700
2,500 gal23630,700
5,000 gal23630,700

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