Berthoud, CO rainwater: 11,477 gallons off a roof
How much rain a roof in Berthoud, CO collects
11,477gallons a year
That is a 1,500 sq ft asphalt roof under Berthoud, CO's normal 14.4 inches of rain, about 795 gallons for every inch that falls.
In Berthoud, 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 Milliken 1.3 Wsw station (5.1 mi away). Berthoud, CO ranks 40th wettest of the 53 cities covered in Colorado.
Month by month in Berthoud
| Month | Rain (in) | Off the roof (gal) | Garden shortfall (gal) |
|---|---|---|---|
| Jan | 0.39 | 310 | |
| Feb | 0.39 | 310 | |
| Mar | 0.92 | 731 | |
| Apr | 1.74 | 1,383 | 325 |
| May | 2.63 | 2,090 | 214 |
| Jun | 1.79 | 1,423 | 319 |
| Jul | 1.54 | 1,224 | 350 |
| Aug | 1.44 | 1,145 | 363 |
| Sep | 1.36 | 1,081 | 373 |
| Oct | 1.08 | 858 | 408 |
| Nov | 0.65 | 517 | |
| Dec | 0.51 | 405 |
May is the wettest month (2.63 in, 2,090 gal off the roof); Jan the driest (0.39 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 Berthoud
Best fit: 2 linked 55-gallon barrels, which delivers about 2,035 gallons to the garden in a normal year (86.5% 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 Berthoud's roof water will pass straight through it.
| Tank | Water used (gal/yr) | Spills over (gal/yr) |
|---|---|---|
| 55 gal | 1,317 | 9,590 |
| 110 gal | 2,035 | 8,872 |
| 165 gal (over cap) | 2,072 | 8,835 |
| 275 gal (over cap) | 2,072 | 8,835 |
| 550 gal (over cap) | 2,072 | 8,835 |
| 1,000 gal (over cap) | 2,072 | 8,835 |
| 1,500 gal (over cap) | 2,072 | 8,835 |
| 2,500 gal (over cap) | 2,072 | 8,835 |
| 5,000 gal (over cap) | 2,072 | 8,835 |
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