Bloomington, IN rainwater: 39,247 gallons off a roof
How much rain a roof in Bloomington, IN collects
39,247gallons a year
That is a 1,500 sq ft asphalt roof under Bloomington, IN's normal 49.4 inches of rain, about 795 gallons for every inch that falls.
In Bloomington, IN 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 Bloomington Indiana Univ station (0.7 mi away). Bloomington, IN ranks 7th wettest of the 88 cities covered in Indiana.
Month by month in Bloomington
| Month | Rain (in) | Off the roof (gal) | Garden shortfall (gal) |
|---|---|---|---|
| Jan | 3.78 | 3,004 | |
| Feb | 2.95 | 2,345 | |
| Mar | 3.66 | 2,909 | |
| Apr | 5.21 | 4,141 | |
| May | 5.36 | 4,260 | |
| Jun | 5.41 | 4,300 | |
| Jul | 4.58 | 3,640 | |
| Aug | 3.38 | 2,686 | 121 |
| Sep | 3.81 | 3,028 | 67 |
| Oct | 3.82 | 3,036 | 66 |
| Nov | 3.93 | 3,124 | |
| Dec | 3.49 | 2,774 |
Jun is the wettest month (5.41 in, 4,300 gal off the roof); Feb the driest (2.95 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 Bloomington
Best fit: one 55-gallon barrel, which delivers about 211 gallons to the garden in a normal year (83.0% 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 Bloomington's roof water will pass straight through it.
| Tank | Water used (gal/yr) | Spills over (gal/yr) |
|---|---|---|
| 55 gal | 211 | 37,807 |
| 110 gal | 211 | 37,807 |
| 165 gal | 211 | 37,807 |
| 275 gal | 211 | 37,807 |
| 550 gal | 211 | 37,807 |
| 1,000 gal | 211 | 37,807 |
| 1,500 gal | 211 | 37,807 |
| 2,500 gal | 211 | 37,807 |
| 5,000 gal | 211 | 37,807 |
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 Indiana?
No statewide rainwater harvesting regulations; check county for local incentives
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