Englewood, CO rainwater: 14,100 gallons off a roof
Englewood, CO: gallons off the roof each year
14,100gallons a year
That is a 1,500 sq ft asphalt roof under Englewood, CO's normal 17.7 inches of rain, about 795 gallons for every inch that falls.
In Englewood, 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 Denver 5.2 S station (2.0 mi away). Englewood, CO ranks 20th wettest of the 53 cities covered in Colorado.
Month by month in Englewood
| Month | Rain (in) | Off the roof (gal) | Garden shortfall (gal) |
|---|---|---|---|
| Jan | 0.60 | 477 | |
| Feb | 0.76 | 604 | |
| Mar | 1.41 | 1,121 | |
| Apr | 2.09 | 1,661 | 282 |
| May | 2.55 | 2,027 | 224 |
| Jun | 2.02 | 1,606 | 290 |
| Jul | 2.19 | 1,741 | 269 |
| Aug | 1.93 | 1,534 | 302 |
| Sep | 1.43 | 1,137 | 364 |
| Oct | 1.26 | 1,001 | 385 |
| Nov | 0.82 | 652 | |
| Dec | 0.68 | 540 |
May is the wettest month (2.55 in, 2,027 gal off the roof); Jan the driest (0.60 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 Englewood
Best fit: 2 linked 55-gallon barrels, which delivers about 1,827 gallons to the garden in a normal year (86.3% of its need).
If you buy one, a 55-gallon barrel with a downspout diverter is the whole job. Check that the overflow points away from your foundation, because most of Englewood's roof water will pass straight through it.
| Tank | Water used (gal/yr) | Spills over (gal/yr) |
|---|---|---|
| 55 gal | 1,488 | 11,982 |
| 110 gal | 1,827 | 11,643 |
| 165 gal (over cap) | 1,827 | 11,643 |
| 275 gal (over cap) | 1,827 | 11,643 |
| 550 gal (over cap) | 1,827 | 11,643 |
| 1,000 gal (over cap) | 1,827 | 11,643 |
| 1,500 gal (over cap) | 1,827 | 11,643 |
| 2,500 gal (over cap) | 1,827 | 11,643 |
| 5,000 gal (over cap) | 1,827 | 11,643 |
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