RoofRainYield

Española, NM rainwater: 8,592 gallons off a roof

How much rain a roof in Española, NM collects

8,592gallons a year

That is a 1,500 sq ft asphalt roof under Española, NM's normal 10.8 inches of rain, about 795 gallons for every inch that falls.

Española, NM has gaps between storms long enough to drain a single barrel. Around 275 gallons of storage catches most of what is worth catching.

Rainfall: NOAA 1991-2020 climate normals, the Espanola 1.1 Se station (1.1 mi away). Española, NM ranks 13th wettest of the 19 cities covered in New Mexico.

Month by month in Española

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan0.54429
Feb0.53421
Mar0.47374
Apr0.60477468
May0.79628444
Jun0.55437474
Jul1.641,303338
Aug1.621,288340
Sep1.15914399
Oct1.411,121367
Nov0.84668
Dec0.67533

Jul is the wettest month (1.64 in, 1,303 gal off the roof); Mar the driest (0.47 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 Española

Best fit: a 275-gallon tote or tank, which delivers about 2,528 gallons to the garden in a normal year (89.4% of its need).

If you set one up, link barrels with a short hose at the base so they fill and drain together, and check the overflow points away from the house.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal1,1007,087
110 gal1,8866,301
165 gal2,1826,005
275 gal2,5285,659
550 gal2,5905,596
1,000 gal2,5905,596
1,500 gal2,5905,596
2,500 gal2,5905,596
5,000 gal2,5905,596

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