Fountain, CO rainwater: 14,394 gallons off a roof
Fountain, CO: gallons off the roof each year
14,394gallons a year
That is a 1,500 sq ft asphalt roof under Fountain, CO's normal 18.1 inches of rain, about 795 gallons for every inch that falls.
In Fountain, CO 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 Colorado Springs 8.2 Se station (4.4 mi away). Fountain, CO ranks 15th wettest of the 53 cities covered in Colorado.
Month by month in Fountain
| Month | Rain (in) | Off the roof (gal) | Garden shortfall (gal) |
|---|---|---|---|
| Jan | 0.44 | 350 | |
| Feb | 0.40 | 318 | |
| Mar | 0.84 | 668 | |
| Apr | 1.92 | 1,526 | 303 |
| May | 1.96 | 1,558 | 298 |
| Jun | 2.09 | 1,661 | 282 |
| Jul | 3.99 | 3,171 | 45 |
| Aug | 3.35 | 2,663 | 125 |
| Sep | 1.37 | 1,089 | 372 |
| Oct | 0.88 | 699 | 433 |
| Nov | 0.52 | 413 | |
| Dec | 0.35 | 278 |
Jul is the wettest month (3.99 in, 3,171 gal off the roof); Dec the driest (0.35 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 Fountain
Best fit: 2 linked 55-gallon barrels, which delivers about 1,493 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 Fountain's roof water will pass straight through it.
| Tank | Water used (gal/yr) | Spills over (gal/yr) |
|---|---|---|
| 55 gal | 1,149 | 12,705 |
| 110 gal | 1,493 | 12,361 |
| 165 gal (over cap) | 1,588 | 12,266 |
| 275 gal (over cap) | 1,633 | 12,221 |
| 550 gal (over cap) | 1,633 | 12,221 |
| 1,000 gal (over cap) | 1,633 | 12,221 |
| 1,500 gal (over cap) | 1,633 | 12,221 |
| 2,500 gal (over cap) | 1,633 | 12,221 |
| 5,000 gal (over cap) | 1,633 | 12,221 |
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 Colorado?
Most households may use rain barrels: a maximum of two rain barrels with a combined storage of 110 gallons or less per household, rooftop runoff only, used outdoors on the same property (HB16-1005). Larger rooftop collection only for qualifying well-permit holders (SB09-080) or pilot projects (HB09-1129).
Checked against the current source on 2026-11-06. Source