RoofRainYield

Victoria, MN rainwater: 26,348 gallons off a roof

How much rain a roof in Victoria, MN collects

26,348gallons a year

That is a 1,500 sq ft asphalt roof under Victoria, MN's normal 33.2 inches of rain, about 795 gallons for every inch that falls.

In Victoria, 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 Victoria 1.6 Wsw station (1.3 mi away). Victoria, MN ranks 39th wettest of the 103 cities covered in Minnesota.

Month by month in Victoria

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan0.89707
Feb0.92731
Mar1.611,280
Apr3.052,424162
May4.293,4107
Jun4.603,656
Jul4.633,680
Aug4.233,36215
Sep3.312,631130
Oct2.782,210196
Nov1.631,296
Dec1.21962

Jul is the wettest month (4.63 in, 3,680 gal off the roof); Jan the driest (0.89 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 Victoria

Best fit: one 55-gallon barrel, which delivers about 410 gallons to the garden in a normal year (80.4% 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 Victoria's roof water will pass straight through it.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal41024,993
110 gal41024,993
165 gal41024,993
275 gal41024,993
550 gal41024,993
1,000 gal41024,993
1,500 gal41024,993
2,500 gal41024,993
5,000 gal41024,993

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