RoofRainYield

Plano, TX rainwater: 32,317 gallons off a roof

Plano, TX: gallons off the roof each year

32,317gallons a year

That is a 1,500 sq ft asphalt roof under Plano, TX's normal 40.7 inches of rain, about 795 gallons for every inch that falls.

In Plano, TX 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 Plano 2.4 Wsw station (2.6 mi away). Plano, TX ranks 101st wettest of the 252 cities covered in Texas.

Month by month in Plano

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan2.692,138
Feb2.862,273
Mar3.682,925
Apr3.532,806102
May5.044,006
Jun4.173,31422
Jul2.161,717273
Aug2.121,685278
Sep3.062,432161
Oct4.873,871
Nov3.132,488
Dec3.352,663

May is the wettest month (5.04 in, 4,006 gal off the roof); Aug the driest (2.12 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 Plano

Best fit: one 55-gallon barrel, which delivers about 680 gallons to the garden in a normal year (81.3% 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 Plano's roof water will pass straight through it.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal68030,752
110 gal72330,709
165 gal72330,709
275 gal72330,709
550 gal72330,709
1,000 gal72330,709
1,500 gal72330,709
2,500 gal72330,709
5,000 gal72330,709

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 Texas?

Rainwater harvesting is legal and encouraged; no state storage cap. HOAs may not adopt new covenants banning rainwater harvesting installations but may require screening. Local taxing units may exempt property with water conservation initiatives from property tax (Tax Code 11.32).

Checked against the current source on 2026-11-06. Source