RoofRainYield

Brandon, MS rainwater: 47,521 gallons off a roof

Rainwater from a roof in Brandon, MS

47,521gallons a year

That is a 1,500 sq ft asphalt roof under Brandon, MS's normal 59.8 inches of rain, about 795 gallons for every inch that falls.

In Brandon, MS a single barrel does most of the work. Storms come often enough that a small tank refills before it runs dry, and a bigger one would mostly sit full.

Rainfall: NOAA 1991-2020 climate normals, the Brandon 1.9 Ne station (1.6 mi away). Brandon, MS ranks 20th wettest of the 41 cities covered in Mississippi.

Month by month in Brandon

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan5.704,530
Feb5.494,363
Mar5.644,483
Apr5.964,737
May4.573,632
Jun4.473,553
Jul4.933,918
Aug4.923,910
Sep4.023,19541
Oct3.903,10056
Nov5.003,974
Dec5.194,125

Apr is the wettest month (5.96 in, 4,737 gal off the roof); Oct the driest (3.90 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 Brandon

Best fit: one 55-gallon barrel, which delivers about 81 gallons to the garden in a normal year (83.3% of its need).

If you set one up, a 55-gallon barrel with a downspout diverter is the whole job. Check that the overflow points away from your foundation, because most of Brandon's roof water will pass straight through it.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal8146,285
110 gal8146,285
165 gal8146,285
275 gal8146,285
550 gal8146,285
1,000 gal8146,285
1,500 gal8146,285
2,500 gal8146,285
5,000 gal8146,285

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