RoofRainYield

Lexington-Fayette urban county, KY rainwater: 39,613 gallons off a roof

Lexington-Fayette urban county, KY: gallons off the roof each year

39,613gallons a year

That is a 1,500 sq ft asphalt roof under Lexington-Fayette urban county, KY's normal 49.8 inches of rain, about 795 gallons for every inch that falls.

In Lexington-Fayette urban county, 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 Lexington Bluegrass Ap station (8.0 mi away). Lexington-Fayette urban county, KY ranks 21st wettest of the 42 cities covered in Kentucky.

Month by month in Lexington-Fayette urban county

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan3.422,718
Feb3.642,893
Mar4.483,561
Apr4.423,513
May5.444,324
Jun4.963,942
Jul5.124,069
Aug3.712,94980
Sep3.422,718116
Oct3.662,90986
Nov3.372,678
Dec4.203,338

May is the wettest month (5.44 in, 4,324 gal off the roof); Nov the driest (3.37 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 Lexington-Fayette urban county

Best fit: one 55-gallon barrel, which delivers about 228 gallons to the garden in a normal year (80.9% of its need).

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

TankWater used (gal/yr)Spills over (gal/yr)
55 gal22838,080
110 gal22838,080
165 gal22838,080
275 gal22838,080
550 gal22838,080
1,000 gal22838,080
1,500 gal22838,080
2,500 gal22838,080
5,000 gal22838,080

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