RoofRainYield

Frankfort, KY rainwater: 40,154 gallons off a roof

Rainwater from a roof in Frankfort, KY

40,154gallons a year

That is a 1,500 sq ft asphalt roof under Frankfort, KY's normal 50.5 inches of rain, about 795 gallons for every inch that falls.

In Frankfort, KY 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 Frankfort 1.9 N station (1.6 mi away). Frankfort, KY ranks 17th wettest of the 42 cities covered in Kentucky.

Month by month in Frankfort

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan3.592,853
Feb3.582,845
Mar4.623,672
Apr4.773,791
May5.194,125
Jun4.833,839
Jul5.444,324
Aug3.652,90187
Sep3.472,758110
Oct3.632,88590
Nov3.632,885
Dec4.123,275

Jul is the wettest month (5.44 in, 4,324 gal off the roof); Sep the driest (3.47 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 Frankfort

Best fit: one 55-gallon barrel, which delivers about 240 gallons to the garden in a normal year (83.7% 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 Frankfort's roof water will pass straight through it.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal24038,699
110 gal24038,699
165 gal24038,699
275 gal24038,699
550 gal24038,699
1,000 gal24038,699
1,500 gal24038,699
2,500 gal24038,699
5,000 gal24038,699

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 Kentucky?

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