RoofRainYield

Pascagoula, MS rainwater: 55,978 gallons off a roof

Pascagoula, MS: gallons off the roof each year

55,978gallons a year

That is a 1,500 sq ft asphalt roof under Pascagoula, MS's normal 70.4 inches of rain, about 795 gallons for every inch that falls.

Pascagoula, MS 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 Pascagoula 3 Ne station (5.3 mi away). Pascagoula, MS ranks 2nd wettest of the 41 cities covered in Mississippi.

Month by month in Pascagoula

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan5.494,363
Feb4.363,465
Mar5.084,038
Apr5.234,157
May5.914,697
Jun7.185,707
Jul8.106,438
Aug8.616,843
Sep6.825,421
Oct4.483,561
Nov4.073,235
Dec5.104,054

Aug is the wettest month (8.61 in, 6,843 gal off the roof); Nov the driest (4.07 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 Pascagoula

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 gal054,868
110 gal054,868
165 gal054,868
275 gal054,868
550 gal054,868
1,000 gal054,868
1,500 gal054,868
2,500 gal054,868
5,000 gal054,868

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 Mississippi?

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