RoofRainYield

Salt Lake City, UT rainwater: 14,084 gallons off a roof

Rainwater from a roof in Salt Lake City, UT

14,084gallons a year

That is a 1,500 sq ft asphalt roof under Salt Lake City, UT's normal 17.7 inches of rain, about 795 gallons for every inch that falls.

Salt Lake City, 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 Salt Lake Triad Ctr station (1.9 mi away). Salt Lake City, UT ranks 42nd wettest of the 67 cities covered in Utah.

Month by month in Salt Lake City

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan1.541,224
Feb1.451,152
Mar2.041,621
Apr2.542,019226
May2.091,661282
Jun1.06842410
Jul0.55437474
Aug0.61485466
Sep1.301,033380
Oct1.391,105369
Nov1.601,272
Dec1.551,232

Apr is the wettest month (2.54 in, 2,019 gal off the roof); Jul the driest (0.55 in). Garden shortfall is what a 200 sq ft vegetable bed needs beyond the rain that lands on it, April to October.

What size rain barrel for Salt Lake City

Best fit: 3 linked 55-gallon barrels, which delivers about 2,153 gallons to the garden in a normal year (82.6% of its need).

If you buy one, 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 gal1,19512,154
110 gal1,84711,502
165 gal2,15311,196
275 gal2,32911,020
550 gal2,32911,020
1,000 gal2,32911,020
1,500 gal2,32911,020
2,500 gal2,32911,020
5,000 gal (over cap)2,32911,020

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