RoofRainYield

Cudahy, CA rainwater: 11,326 gallons off a roof

Cudahy, CA: gallons off the roof each year

11,326gallons a year

That is a 1,500 sq ft asphalt roof under Cudahy, CA's normal 14.3 inches of rain, about 795 gallons for every inch that falls.

Cudahy, CA's rain arrives in a wet season and stops, so storage is what matters. It takes a cistern of 2,500 gallons to carry spring rain into the dry months.

Rainfall: NOAA 1991-2020 climate normals, the Los Angeles Dwtn Usc Campus station (6.7 mi away). Cudahy, CA ranks 203rd wettest of the 376 cities covered in California.

Month by month in Cudahy

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan3.292,615
Feb3.642,893
Mar2.231,772
Apr0.69548456
May0.32254502
Jun0.0972531
Jul0.0216540
Aug0.000542
Sep0.13103526
Oct0.58461470
Nov0.78620
Dec2.481,971

Feb is the wettest month (3.64 in, 2,893 gal off the roof); Aug the driest (0.00 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 Cudahy

Best fit: a 2,500-gallon cistern, which delivers about 3,195 gallons to the garden in a normal year (89.5% of its need).

If you set one up, 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 gal22010,600
110 gal44010,380
165 gal66010,160
275 gal9709,850
550 gal1,2459,575
1,000 gal1,6959,125
1,500 gal2,1958,625
2,500 gal3,1957,625
5,000 gal3,5227,299

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 California?

Legal. Use of rainwater collected from rooftops does not require a water right permit (Rainwater Capture Act of 2012, Water Code 10570 et seq.). The Act does not change existing water rights; local building/plumbing codes still apply to installed systems.

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