RoofRainYield

Liberal, KS rainwater: 16,778 gallons off a roof

Rainwater from a roof in Liberal, KS

16,778gallons a year

That is a 1,500 sq ft asphalt roof under Liberal, KS's normal 21.1 inches of rain, about 795 gallons for every inch that falls.

In Liberal, KS 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 Liberal station (1.6 mi away). Liberal, KS ranks 37th wettest of the 38 cities covered in Kansas.

Month by month in Liberal

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan0.47374
Feb0.40318
Mar1.20954
Apr1.801,431318
May2.662,114211
Jun3.312,631130
Jul3.202,543143
Aug2.722,162203
Sep1.531,216352
Oct2.291,820257
Nov0.73580
Dec0.80636

Jun is the wettest month (3.31 in, 2,631 gal off the roof); Feb the driest (0.40 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 Liberal?

Best fit: 2 linked 55-gallon barrels, which delivers about 1,408 gallons to the garden in a normal year (87.3% of its need).

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

TankWater used (gal/yr)Spills over (gal/yr)
55 gal1,16515,044
110 gal1,40814,800
165 gal1,40814,800
275 gal1,40814,800
550 gal1,40814,800
1,000 gal1,40814,800
1,500 gal1,40814,800
2,500 gal1,40814,800
5,000 gal1,40814,800

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 Kansas?

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