RoofRainYield

Belvidere, IL rainwater: 31,093 gallons off a roof

How much rain a roof in Belvidere, IL collects

31,093gallons a year

That is a 1,500 sq ft asphalt roof under Belvidere, IL's normal 39.1 inches of rain, about 795 gallons for every inch that falls.

In Belvidere, 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 Belvidere station (1.4 mi away). Belvidere, IL ranks 154th wettest of the 225 cities covered in Illinois.

Month by month in Belvidere

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan1.711,359
Feb1.671,327
Mar2.281,812
Apr3.783,00471
May4.133,28327
Jun5.884,673
Jul4.013,18742
Aug4.723,751
Sep3.622,87791
Oct2.982,369171
Nov2.291,820
Dec2.051,629

Jun is the wettest month (5.88 in, 4,673 gal off the roof); Feb the driest (1.67 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 Belvidere

Best fit: one 55-gallon barrel, which delivers about 322 gallons to the garden in a normal year (80.0% 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 Belvidere's roof water will pass straight through it.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal32229,706
110 gal32229,706
165 gal32229,706
275 gal32229,706
550 gal32229,706
1,000 gal32229,706
1,500 gal32229,706
2,500 gal32229,706
5,000 gal32229,706

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