RoofRainYield

Sevierville, TN rainwater: 38,771 gallons off a roof

How much rain a roof in Sevierville, TN collects

38,771gallons a year

That is a 1,500 sq ft asphalt roof under Sevierville, TN's normal 48.8 inches of rain, about 795 gallons for every inch that falls.

In Sevierville, TN 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 Sevierville station (3.0 mi away). Sevierville, TN ranks 58th wettest of the 65 cities covered in Tennessee.

Month by month in Sevierville

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan4.413,505
Feb4.263,386
Mar4.693,728
Apr4.323,4344
May3.873,07660
Jun4.263,38611
Jul4.653,696
Aug3.402,702118
Sep3.562,83098
Oct2.902,305181
Nov3.562,830
Dec4.903,895

Dec is the wettest month (4.90 in, 3,895 gal off the roof); Oct the driest (2.90 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 Sevierville?

Best fit: one 55-gallon barrel, which delivers about 379 gallons to the garden in a normal year (80.2% 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 Sevierville's roof water will pass straight through it.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal37937,116
110 gal37937,116
165 gal37937,116
275 gal37937,116
550 gal37937,116
1,000 gal37937,116
1,500 gal37937,116
2,500 gal37937,116
5,000 gal37937,116

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 Tennessee?

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