Ardmore, OK rainwater: 30,226 gallons off a roof
How much rain a roof in Ardmore, OK collects
30,226gallons a year
That is a 1,500 sq ft asphalt roof under Ardmore, OK's normal 38.0 inches of rain, about 795 gallons for every inch that falls.
In Ardmore, OK 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 Ardmore station (2.2 mi away). Ardmore, OK ranks 20th wettest of the 45 cities covered in Oklahoma.
Month by month in Ardmore
| Month | Rain (in) | Off the roof (gal) | Garden shortfall (gal) |
|---|---|---|---|
| Jan | 1.84 | 1,462 | |
| Feb | 2.21 | 1,757 | |
| Mar | 2.81 | 2,233 | |
| Apr | 3.28 | 2,607 | 133 |
| May | 5.72 | 4,546 | |
| Jun | 4.58 | 3,640 | |
| Jul | 2.49 | 1,979 | 232 |
| Aug | 2.67 | 2,122 | 209 |
| Sep | 3.60 | 2,861 | 94 |
| Oct | 3.86 | 3,068 | 61 |
| Nov | 2.37 | 1,884 | |
| Dec | 2.60 | 2,066 |
May is the wettest month (5.72 in, 4,546 gal off the roof); Jan the driest (1.84 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 Ardmore
Best fit: one 55-gallon barrel, which delivers about 628 gallons to the garden in a normal year (86.1% 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 Ardmore's roof water will pass straight through it.
| Tank | Water used (gal/yr) | Spills over (gal/yr) |
|---|---|---|
| 55 gal | 628 | 28,774 |
| 110 gal | 628 | 28,774 |
| 165 gal | 628 | 28,774 |
| 275 gal | 628 | 28,774 |
| 550 gal | 628 | 28,774 |
| 1,000 gal | 628 | 28,774 |
| 1,500 gal | 628 | 28,774 |
| 2,500 gal | 628 | 28,774 |
| 5,000 gal | 628 | 28,774 |
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 Oklahoma?
Encouraged through state legislation: Water for 2060 Act
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