RoofRainYield

Minden, LA rainwater: 45,773 gallons off a roof

How much rain a roof in Minden, LA collects

45,773gallons a year

That is a 1,500 sq ft asphalt roof under Minden, LA's normal 57.6 inches of rain, about 795 gallons for every inch that falls.

In Minden, LA 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 Minden station (1.6 mi away). Minden, LA ranks 30th wettest of the 35 cities covered in Louisiana.

Month by month in Minden

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan5.274,189
Feb5.013,982
Mar5.664,499
Apr6.455,126
May4.893,887
Jun4.933,918
Jul3.682,92584
Aug3.242,575138
Sep3.692,93382
Oct4.683,720
Nov4.363,465
Dec5.734,554

Apr is the wettest month (6.45 in, 5,126 gal off the roof); Aug the driest (3.24 in). Garden shortfall is what a 200 sq ft vegetable bed needs beyond the rain that lands on it, April to October.

Barrel or cistern in Minden?

Best fit: one 55-gallon barrel, which delivers about 252 gallons to the garden in a normal year (82.8% 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 Minden's roof water will pass straight through it.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal25244,426
110 gal25244,426
165 gal25244,426
275 gal25244,426
550 gal25244,426
1,000 gal25244,426
1,500 gal25244,426
2,500 gal25244,426
5,000 gal25244,426

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