RoofRainYield

Lebanon, MO rainwater: 37,054 gallons off a roof

Lebanon, MO: gallons off the roof each year

37,054gallons a year

That is a 1,500 sq ft asphalt roof under Lebanon, MO's normal 46.6 inches of rain, about 795 gallons for every inch that falls.

In Lebanon, MO 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 Lebanon 1.3 E station (1.3 mi away). Lebanon, MO ranks 11th wettest of the 80 cities covered in Missouri.

Month by month in Lebanon

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan2.702,146
Feb2.632,090
Mar3.532,806
Apr4.993,966
May5.964,737
Jun4.223,35416
Jul4.073,23535
Aug3.893,09257
Sep4.643,688
Oct3.572,83797
Nov3.542,814
Dec2.882,289

May is the wettest month (5.96 in, 4,737 gal off the roof); Feb the driest (2.63 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 Lebanon

Best fit: one 55-gallon barrel, which delivers about 166 gallons to the garden in a normal year (80.7% 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 Lebanon's roof water will pass straight through it.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal16635,867
110 gal16635,867
165 gal16635,867
275 gal16635,867
550 gal16635,867
1,000 gal16635,867
1,500 gal16635,867
2,500 gal16635,867
5,000 gal16635,867

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 Missouri?

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