RoofRainYield

Ashland, KY rainwater: 37,102 gallons off a roof

Rainwater from a roof in Ashland, KY

37,102gallons a year

That is a 1,500 sq ft asphalt roof under Ashland, KY's normal 46.7 inches of rain, about 795 gallons for every inch that falls.

In Ashland, 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 Ashland station (1.8 mi away). Ashland, KY ranks 35th wettest of the 42 cities covered in Kentucky.

Month by month in Ashland

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan3.512,790
Feb3.692,933
Mar4.363,465
Apr3.853,06062
May4.853,855
Jun4.463,545
Jul4.583,640
Aug3.913,10855
Sep3.322,639128
Oct2.972,361172
Nov2.982,369
Dec4.203,338

May is the wettest month (4.85 in, 3,855 gal off the roof); Oct the driest (2.97 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 Ashland

Best fit: one 55-gallon barrel, which delivers about 331 gallons to the garden in a normal year (79.3% 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 Ashland's roof water will pass straight through it.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal33135,405
110 gal33135,405
165 gal33135,405
275 gal33135,405
550 gal33135,405
1,000 gal33135,405
1,500 gal33135,405
2,500 gal33135,405
5,000 gal33135,405

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