Kearns, UT rainwater: 16,079 gallons off a roof

Kearns, UT: gallons off the roof each year

16,079gallons a year

That is a 1,500 sq ft asphalt roof under Kearns, UT's normal 20.2 inches of rain, about 795 gallons for every inch that falls.

Kearns, 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 Taylorsville-Bennion 2.0 Wsw station (1.5 mi away). Kearns, UT ranks 25th wettest of the 67 cities covered in Utah.

Month by month in Kearns

Month	Rain (in)	Off the roof (gal)	Garden shortfall (gal)
Jan	1.79	1,423
Feb	1.73	1,375
Mar	2.18	1,733
Apr	2.67	2,122	209
May	2.63	2,090	214
Jun	1.19	946	394
Jul	0.83	660	439
Aug	0.85	676	436
Sep	1.22	970	390
Oct	1.76	1,399	323
Nov	1.63	1,296
Dec	1.75	1,391

Apr is the wettest month (2.67 in, 2,122 gal off the roof); Jul the driest (0.83 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 Kearns

Best fit: 3 linked 55-gallon barrels, which delivers about 2,027 gallons to the garden in a normal year (84.2% 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	1,128	14,231
110 gal	1,736	13,623
165 gal	2,027	13,332
275 gal	2,153	13,206
550 gal	2,153	13,206
1,000 gal	2,153	13,206
1,500 gal	2,153	13,206
2,500 gal	2,153	13,206
5,000 gal (over cap)	2,153	13,206

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