RoofRainYield

Hastings, MN rainwater: 26,491 gallons off a roof

Hastings, MN: gallons off the roof each year

26,491gallons a year

That is a 1,500 sq ft asphalt roof under Hastings, MN's normal 33.3 inches of rain, about 795 gallons for every inch that falls.

In Hastings, MN 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 Hastings Dam 2 station (2.1 mi away). Hastings, MN ranks 34th wettest of the 103 cities covered in Minnesota.

Month by month in Hastings

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan0.90715
Feb0.91723
Mar1.781,415
Apr3.102,464156
May4.333,4422
Jun4.943,926
Jul4.373,473
Aug4.233,36215
Sep3.212,551142
Oct2.612,074217
Nov1.721,367
Dec1.23978

Jun is the wettest month (4.94 in, 3,926 gal off the roof); Jan the driest (0.90 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 Hastings

Best fit: one 55-gallon barrel, which delivers about 422 gallons to the garden in a normal year (79.3% 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 Hastings's roof water will pass straight through it.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal42225,064
110 gal42225,064
165 gal42225,064
275 gal42225,064
550 gal42225,064
1,000 gal42225,064
1,500 gal42225,064
2,500 gal42225,064
5,000 gal42225,064

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 Minnesota?

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