Alpine, UT rainwater: 16,786 gallons off a roof

How much rain a roof in Alpine, UT collects

16,786gallons a year

That is a 1,500 sq ft asphalt roof under Alpine, UT's normal 21.1 inches of rain, about 795 gallons for every inch that falls.

Alpine, UT has gaps between storms long enough to drain a single barrel. Around 165 gallons of storage catches most of what is worth catching.

Rainfall: NOAA 1991-2020 climate normals, the Alpine station (0.1 mi away). Alpine, UT ranks 17th wettest of the 67 cities covered in Utah.

Month by month in Alpine

Month	Rain (in)	Off the roof (gal)	Garden shortfall (gal)
Jan	2.50	1,987
Feb	2.03	1,613
Mar	2.03	1,613
Apr	2.49	1,979	232
May	2.42	1,923	241
Jun	1.00	795	418
Jul	0.64	509	463
Aug	0.95	755	424
Sep	1.33	1,057	377
Oct	1.84	1,462	313
Nov	1.63	1,296
Dec	2.26	1,796

Jan is the wettest month (2.50 in, 1,987 gal off the roof); Jul the driest (0.64 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 Alpine

Best fit: 3 linked 55-gallon barrels, which delivers about 2,055 gallons to the garden in a normal year (83.3% of its need).

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

Tank	Water used (gal/yr)	Spills over (gal/yr)
55 gal	1,157	14,775
110 gal	1,779	14,152
165 gal	2,055	13,876
275 gal	2,189	13,743
550 gal	2,189	13,743
1,000 gal	2,189	13,743
1,500 gal	2,189	13,743
2,500 gal	2,189	13,743
5,000 gal (over cap)	2,189	13,743

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 Utah?

Up to 2 covered containers of max 100 gal each with no registration; with free registration at the Utah Division of Water Rights, total storage up to 2,500 gal. Use limited to the same parcel where captured.

Checked against the current source on 2026-11-06. Source