RoofRainYield

Dickinson, ND rainwater: 14,839 gallons off a roof

Rainwater from a roof in Dickinson, ND

14,839gallons a year

That is a 1,500 sq ft asphalt roof under Dickinson, ND's normal 18.7 inches of rain, about 795 gallons for every inch that falls.

In Dickinson, ND 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 Dickinson 1.3 Wnw station (0.6 mi away). Dickinson, ND ranks 6th wettest of the 9 cities covered in North Dakota.

Month by month in Dickinson

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan0.48382
Feb0.51405
Mar0.78620
Apr1.461,160360
May2.822,241191
Jun3.172,520147
Jul2.682,130208
Aug1.741,383325
Sep1.891,502307
Oct1.481,176358
Nov0.97771
Dec0.69548

Jun is the wettest month (3.17 in, 2,520 gal off the roof); Jan the driest (0.48 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 Dickinson

Best fit: 2 linked 55-gallon barrels, which delivers about 1,630 gallons to the garden in a normal year (86.0% 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 Dickinson's roof water will pass straight through it.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal1,26312,946
110 gal1,63012,579
165 gal1,63012,579
275 gal1,63012,579
550 gal1,63012,579
1,000 gal1,63012,579
1,500 gal1,63012,579
2,500 gal1,63012,579
5,000 gal1,63012,579

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 North Dakota?

No rainwater harvesting regulations

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