RoofRainYield

New Iberia, LA rainwater: 47,442 gallons off a roof

Rainwater from a roof in New Iberia, LA

47,442gallons a year

That is a 1,500 sq ft asphalt roof under New Iberia, LA's normal 59.7 inches of rain, about 795 gallons for every inch that falls.

New Iberia, LA gets enough rain in the growing season that a 200 sq ft garden rarely needs topping up, so a tank here is about saving the occasional dry spell, not a summer of watering.

Rainfall: NOAA 1991-2020 climate normals, the New Iberia Acadiana Rgnl Ap station (4.4 mi away). New Iberia, LA ranks 27th wettest of the 35 cities covered in Louisiana.

Month by month in New Iberia

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan5.364,260
Feb3.542,814
Mar2.912,313
Apr4.823,831
May4.393,489
Jun6.465,134
Jul6.715,333
Aug6.375,063
Sep5.054,014
Oct5.094,046
Nov4.503,577
Dec4.493,569

Jul is the wettest month (6.71 in, 5,333 gal off the roof); Mar the driest (2.91 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 New Iberia

Best fit: a 5,000-gallon cistern, which delivers about 0 gallons to the garden in a normal year.

Before you buy, a single 55-gallon barrel is plenty here; spend the money on a first-flush diverter and a screen rather than more storage.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal046,302
110 gal046,302
165 gal046,302
275 gal046,302
550 gal046,302
1,000 gal046,302
1,500 gal046,302
2,500 gal046,302
5,000 gal046,302

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 Louisiana?

No rainwater harvesting regulations

From the 2015 (Pacific Northwest National Laboratory report 24347); not yet re-checked against current law, so check with your state water agency before building anything large. Source