RoofRainYield

Auburn, IN rainwater: 29,448 gallons off a roof

Auburn, IN: gallons off the roof each year

29,448gallons a year

That is a 1,500 sq ft asphalt roof under Auburn, IN's normal 37.1 inches of rain, about 795 gallons for every inch that falls.

In Auburn, 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 Auburn 0.8 Ne station (0.6 mi away). Auburn, IN ranks 88th wettest of the 88 cities covered in Indiana.

Month by month in Auburn

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan2.361,876
Feb2.081,653
Mar2.522,003
Apr3.642,89389
May4.453,537
Jun3.933,12452
Jul3.462,750111
Aug3.622,87791
Sep3.102,464156
Oct2.702,146206
Nov2.782,210
Dec2.411,915

May is the wettest month (4.45 in, 3,537 gal off the roof); Feb the driest (2.08 in). Garden shortfall is what a 200 sq ft vegetable bed needs beyond the rain that lands on it, April to October.

Which tank size is worth it in Auburn

Best fit: one 55-gallon barrel, which delivers about 547 gallons to the garden in a normal year (77.7% 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 Auburn's roof water will pass straight through it.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal54727,655
110 gal54727,655
165 gal54727,655
275 gal54727,655
550 gal54727,655
1,000 gal54727,655
1,500 gal54727,655
2,500 gal54727,655
5,000 gal54727,655

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