RoofRainYield

Natchez, MS rainwater: 46,647 gallons off a roof

Natchez, MS: gallons off the roof each year

46,647gallons a year

That is a 1,500 sq ft asphalt roof under Natchez, MS's normal 58.7 inches of rain, about 795 gallons for every inch that falls.

In Natchez, 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 Vidalia #2 station (3.2 mi away). Natchez, MS ranks 29th wettest of the 41 cities covered in Mississippi.

Month by month in Natchez

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan5.674,507
Feb5.444,324
Mar5.003,974
Apr5.064,022
May4.053,21937
Jun5.023,990
Jul4.653,696
Aug5.434,316
Sep3.943,13251
Oct4.313,4265
Nov5.054,014
Dec5.074,030

Jan is the wettest month (5.67 in, 4,507 gal off the roof); Sep the driest (3.94 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 Natchez

Best fit: one 55-gallon barrel, which delivers about 80 gallons to the garden in a normal year (85.6% of its need).

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

TankWater used (gal/yr)Spills over (gal/yr)
55 gal8045,682
110 gal8045,682
165 gal8045,682
275 gal8045,682
550 gal8045,682
1,000 gal8045,682
1,500 gal8045,682
2,500 gal8045,682
5,000 gal8045,682

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