RoofRainYield

Shorewood, IL rainwater: 31,967 gallons off a roof

Shorewood, IL: gallons off the roof each year

31,967gallons a year

That is a 1,500 sq ft asphalt roof under Shorewood, IL's normal 40.2 inches of rain, about 795 gallons for every inch that falls.

In Shorewood, IL 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 Joliet 2.9 Wnw station (2.7 mi away). Shorewood, IL ranks 104th wettest of the 225 cities covered in Illinois.

Month by month in Shorewood

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan2.171,725
Feb1.901,510
Mar2.501,987
Apr3.953,13950
May4.673,712
Jun4.773,791
Jul4.403,497
Aug4.283,4029
Sep3.282,607133
Oct3.392,694120
Nov2.742,178
Dec2.171,725

Jun is the wettest month (4.77 in, 3,791 gal off the roof); Feb the driest (1.90 in). Garden shortfall is what a 200 sq ft vegetable bed needs beyond the rain that lands on it, April to October.

What size rain barrel for Shorewood

Best fit: one 55-gallon barrel, which delivers about 237 gallons to the garden in a normal year (76.0% 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 Shorewood's roof water will pass straight through it.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal23730,470
110 gal23730,470
165 gal23730,470
275 gal23730,470
550 gal23730,470
1,000 gal23730,470
1,500 gal23730,470
2,500 gal23730,470
5,000 gal23730,470

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 Illinois?

Local government can regulate rainwater harvesting per state plumbing law

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