RoofRainYield

Sparks, NV rainwater: 6,660 gallons off a roof

How much rain a roof in Sparks, NV collects

6,660gallons a year

That is a 1,500 sq ft asphalt roof under Sparks, NV's normal 8.4 inches of rain, about 795 gallons for every inch that falls.

Sparks, NV's rain arrives in a wet season and stops, so storage is what matters. It takes a cistern of 1,000 gallons to carry spring rain into the dry months.

Rainfall: NOAA 1991-2020 climate normals, the Sparks station (1.6 mi away). Sparks, NV ranks 4th wettest of the 10 cities covered in Nevada.

Month by month in Sparks

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan1.281,017
Feb1.00795
Mar0.85676
Apr0.51405479
May0.69548456
Jun0.39310494
Jul0.42334490
Aug0.28223507
Sep0.24191512
Oct0.91723429
Nov0.70556
Dec1.11882

Jan is the wettest month (1.28 in, 1,017 gal off the roof); Sep the driest (0.24 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 Sparks?

Best fit: a 1,000-gallon cistern, which delivers about 3,072 gallons to the garden in a normal year (91.2% of its need).

If you buy one, ask about a rebate first: cistern-sized storage costs real money, and a buried or tall tank may need a permit. Place it where a full tank (about 8.3 lb a gallon) sits on firm, level ground.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal6055,695
110 gal1,1975,104
165 gal1,6944,607
275 gal2,2834,017
550 gal2,6223,678
1,000 gal3,0723,228
1,500 gal3,2133,088
2,500 gal3,2133,088
5,000 gal3,2131,175

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 Nevada?

Nevada law changed after 2015 (AB138, 2017 session). The current rule has not been verified here yet; check with the Nevada Division of Water Resources before installing.

From the stale; not yet re-checked against current law, so check with your state water agency before building anything large. Source