RoofRainYield

Mount Pleasant, WI rainwater: 29,996 gallons off a roof

How much rain a roof in Mount Pleasant, WI collects

29,996gallons a year

That is a 1,500 sq ft asphalt roof under Mount Pleasant, WI's normal 37.7 inches of rain, about 795 gallons for every inch that falls.

In Mount Pleasant, 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 Racine 2.3 Wsw station (2.0 mi away). Mount Pleasant, WI ranks 15th wettest of the 98 cities covered in Wisconsin.

Month by month in Mount Pleasant

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan2.011,598
Feb2.221,764
Mar2.562,035
Apr4.053,21937
May4.103,25931
Jun4.523,593
Jul3.522,798103
Aug3.632,88590
Sep3.392,694120
Oct3.172,520147
Nov2.522,003
Dec2.051,629

Jun is the wettest month (4.52 in, 3,593 gal off the roof); Jan the driest (2.01 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 Mount Pleasant

Best fit: one 55-gallon barrel, which delivers about 421 gallons to the garden in a normal year (79.6% 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 Mount Pleasant's roof water will pass straight through it.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal42128,510
110 gal42128,510
165 gal42128,510
275 gal42128,510
550 gal42128,510
1,000 gal42128,510
1,500 gal42128,510
2,500 gal42128,510
5,000 gal42128,510

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