Greenwood, IN rainwater: 37,133 gallons off a roof
Rainwater from a roof in Greenwood, IN
37,133gallons a year
That is a 1,500 sq ft asphalt roof under Greenwood, IN's normal 46.7 inches of rain, about 795 gallons for every inch that falls.
In Greenwood, 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 Greenwood 4.6 Sw station (4.4 mi away). Greenwood, IN ranks 16th wettest of the 88 cities covered in Indiana.
Month by month in Greenwood
| Month | Rain (in) | Off the roof (gal) | Garden shortfall (gal) |
|---|---|---|---|
| Jan | 3.25 | 2,583 | |
| Feb | 2.55 | 2,027 | |
| Mar | 3.74 | 2,973 | |
| Apr | 4.97 | 3,950 | |
| May | 4.95 | 3,934 | |
| Jun | 5.18 | 4,117 | |
| Jul | 4.59 | 3,648 | |
| Aug | 3.87 | 3,076 | 60 |
| Sep | 3.33 | 2,647 | 127 |
| Oct | 3.36 | 2,671 | 123 |
| Nov | 3.55 | 2,822 | |
| Dec | 3.38 | 2,686 |
Jun is the wettest month (5.18 in, 4,117 gal off the roof); Feb the driest (2.55 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 Greenwood?
Best fit: one 55-gallon barrel, which delivers about 256 gallons to the garden in a normal year (82.5% of its need).
If you buy one, a 55-gallon barrel with a downspout diverter is the whole job. Check that the overflow points away from your foundation, because most of Greenwood's roof water will pass straight through it.
| Tank | Water used (gal/yr) | Spills over (gal/yr) |
|---|---|---|
| 55 gal | 256 | 35,693 |
| 110 gal | 256 | 35,693 |
| 165 gal | 256 | 35,693 |
| 275 gal | 256 | 35,693 |
| 550 gal | 256 | 35,693 |
| 1,000 gal | 256 | 35,693 |
| 1,500 gal | 256 | 35,693 |
| 2,500 gal | 256 | 35,693 |
| 5,000 gal | 256 | 35,693 |
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