RoofRainYield

Morton Grove, IL rainwater: 32,794 gallons off a roof

Rainwater from a roof in Morton Grove, IL

32,794gallons a year

That is a 1,500 sq ft asphalt roof under Morton Grove, IL's normal 41.3 inches of rain, about 795 gallons for every inch that falls.

In Morton Grove, 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 Harwood Heights 0.4 Nne station (4.9 mi away). Morton Grove, IL ranks 51st wettest of the 225 cities covered in Illinois.

Month by month in Morton Grove

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan2.251,788
Feb2.041,621
Mar2.391,900
Apr3.963,14749
May4.873,871
Jun4.683,720
Jul3.672,91785
Aug5.114,061
Sep3.642,89389
Oct3.642,89389
Nov2.732,170
Dec2.281,812

Aug is the wettest month (5.11 in, 4,061 gal off the roof); Feb the driest (2.04 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 Morton Grove

Best fit: one 55-gallon barrel, which delivers about 246 gallons to the garden in a normal year (79.2% 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 Morton Grove's roof water will pass straight through it.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal24631,407
110 gal24631,407
165 gal24631,407
275 gal24631,407
550 gal24631,407
1,000 gal24631,407
1,500 gal24631,407
2,500 gal24631,407
5,000 gal24631,407

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