Las Vegas, NM rainwater: 13,289 gallons off a roof
How much rain a roof in Las Vegas, NM collects
13,289gallons a year
That is a 1,500 sq ft asphalt roof under Las Vegas, NM's normal 16.7 inches of rain, about 795 gallons for every inch that falls.
In Las Vegas, NM 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 Las Vegas Wwtp station (2.6 mi away). Las Vegas, NM ranks 2nd wettest of the 19 cities covered in New Mexico.
Month by month in Las Vegas
| Month | Rain (in) | Off the roof (gal) | Garden shortfall (gal) |
|---|---|---|---|
| Jan | 0.42 | 334 | |
| Feb | 0.45 | 358 | |
| Mar | 0.56 | 445 | |
| Apr | 0.70 | 556 | 455 |
| May | 1.49 | 1,184 | 357 |
| Jun | 1.36 | 1,081 | 373 |
| Jul | 3.19 | 2,535 | 145 |
| Aug | 3.12 | 2,480 | 153 |
| Sep | 2.43 | 1,931 | 239 |
| Oct | 1.69 | 1,343 | 332 |
| Nov | 0.57 | 453 | |
| Dec | 0.74 | 588 |
Jul is the wettest month (3.19 in, 2,535 gal off the roof); Jan the driest (0.42 in). Garden shortfall is what a 200 sq ft vegetable bed needs beyond the rain that lands on it, April to October.
Barrel or cistern in Las Vegas?
Best fit: 2 linked 55-gallon barrels, which delivers about 1,651 gallons to the garden in a normal year (80.4% 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 Las Vegas's roof water will pass straight through it.
| Tank | Water used (gal/yr) | Spills over (gal/yr) |
|---|---|---|
| 55 gal | 1,117 | 11,617 |
| 110 gal | 1,651 | 11,084 |
| 165 gal | 1,773 | 10,962 |
| 275 gal | 1,820 | 10,914 |
| 550 gal | 1,820 | 10,914 |
| 1,000 gal | 1,820 | 10,914 |
| 1,500 gal | 1,820 | 10,914 |
| 2,500 gal | 1,820 | 10,914 |
| 5,000 gal | 1,820 | 10,914 |
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 New Mexico?
Regulated through the State Engineer Office; no specific requirements exist for outdoor uses; indoor uses must meet quality standards; 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