RoofRainYield

Schaumburg, IL rainwater: 31,474 gallons off a roof

How much rain a roof in Schaumburg, IL collects

31,474gallons a year

That is a 1,500 sq ft asphalt roof under Schaumburg, IL's normal 39.6 inches of rain, about 795 gallons for every inch that falls.

In Schaumburg, 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 Schaumburg 2.0 E station (2.0 mi away). Schaumburg, IL ranks 129th wettest of the 225 cities covered in Illinois.

Month by month in Schaumburg

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan1.981,574
Feb1.961,558
Mar2.481,971
Apr3.843,05264
May4.763,783
Jun4.523,593
Jul3.923,11654
Aug4.303,4186
Sep3.382,686121
Oct3.472,758110
Nov2.742,178
Dec2.251,788

May is the wettest month (4.76 in, 3,783 gal off the roof); Feb the driest (1.96 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 Schaumburg?

Best fit: one 55-gallon barrel, which delivers about 276 gallons to the garden in a normal year (77.9% of its need).

Before you buy, a 55-gallon barrel with a downspout diverter is the whole job. Check that the overflow points away from your foundation, because most of Schaumburg's roof water will pass straight through it.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal27629,998
110 gal27629,998
165 gal27629,998
275 gal27629,998
550 gal27629,998
1,000 gal27629,998
1,500 gal27629,998
2,500 gal27629,998
5,000 gal27629,998

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