RoofRainYield

Mountain Home, AR rainwater: 40,424 gallons off a roof

Mountain Home, AR: gallons off the roof each year

40,424gallons a year

That is a 1,500 sq ft asphalt roof under Mountain Home, AR's normal 50.9 inches of rain, about 795 gallons for every inch that falls.

In Mountain Home, AR 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 Mtn Home 1 Nnw station (0.9 mi away). Mountain Home, AR ranks 23rd wettest of the 39 cities covered in Arkansas.

Month by month in Mountain Home

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan3.302,623
Feb3.262,591
Mar5.033,998
Apr5.604,451
May5.684,514
Jun3.883,08459
Jul4.153,29825
Aug3.742,97376
Sep3.662,90986
Oct3.993,17145
Nov4.803,815
Dec3.772,996

May is the wettest month (5.68 in, 4,514 gal off the roof); Feb the driest (3.26 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 Mountain Home

Best fit: one 55-gallon barrel, which delivers about 239 gallons to the garden in a normal year (82.3% 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 Mountain Home's roof water will pass straight through it.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal23939,060
110 gal23939,060
165 gal23939,060
275 gal23939,060
550 gal23939,060
1,000 gal23939,060
1,500 gal23939,060
2,500 gal23939,060
5,000 gal23939,060

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 Arkansas?

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