St. Cloud, MN rainwater: 24,075 gallons off a roof
Rainwater from a roof in St. Cloud, MN
24,075gallons a year
That is a 1,500 sq ft asphalt roof under St. Cloud, MN's normal 30.3 inches of rain, about 795 gallons for every inch that falls.
In St. Cloud, 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 Sartell 1.4 Sse station (5.4 mi away). St. Cloud, MN ranks 82nd wettest of the 103 cities covered in Minnesota.
Month by month in St. Cloud
| Month | Rain (in) | Off the roof (gal) | Garden shortfall (gal) |
|---|---|---|---|
| Jan | 0.70 | 556 | |
| Feb | 0.79 | 628 | |
| Mar | 1.50 | 1,192 | |
| Apr | 2.67 | 2,122 | 209 |
| May | 3.73 | 2,965 | 77 |
| Jun | 4.47 | 3,553 | |
| Jul | 4.41 | 3,505 | |
| Aug | 3.87 | 3,076 | 60 |
| Sep | 3.05 | 2,424 | 162 |
| Oct | 2.67 | 2,122 | 209 |
| Nov | 1.51 | 1,200 | |
| Dec | 0.92 | 731 |
Jun is the wettest month (4.47 in, 3,553 gal off the roof); Jan the driest (0.70 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 St. Cloud
Best fit: one 55-gallon barrel, which delivers about 586 gallons to the garden in a normal year (81.6% 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 St. Cloud's roof water will pass straight through it.
| Tank | Water used (gal/yr) | Spills over (gal/yr) |
|---|---|---|
| 55 gal | 586 | 22,618 |
| 110 gal | 586 | 22,618 |
| 165 gal | 586 | 22,618 |
| 275 gal | 586 | 22,618 |
| 550 gal | 586 | 22,618 |
| 1,000 gal | 586 | 22,618 |
| 1,500 gal | 586 | 22,618 |
| 2,500 gal | 586 | 22,618 |
| 5,000 gal | 586 | 22,618 |
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