Westbury, NY rainwater: 36,029 gallons off a roof
How much rain a roof in Westbury, NY collects
36,029gallons a year
That is a 1,500 sq ft asphalt roof under Westbury, NY's normal 45.3 inches of rain, about 795 gallons for every inch that falls.
In Westbury, NY 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 Mineola station (2.4 mi away). Westbury, NY ranks 54th wettest of the 90 cities covered in New York.
Month by month in Westbury
| Month | Rain (in) | Off the roof (gal) | Garden shortfall (gal) |
|---|---|---|---|
| Jan | 3.65 | 2,901 | |
| Feb | 3.00 | 2,384 | |
| Mar | 4.41 | 3,505 | |
| Apr | 3.75 | 2,981 | 75 |
| May | 3.13 | 2,488 | 152 |
| Jun | 3.80 | 3,020 | 69 |
| Jul | 4.04 | 3,211 | 39 |
| Aug | 3.92 | 3,116 | 54 |
| Sep | 4.08 | 3,243 | 34 |
| Oct | 4.02 | 3,195 | 41 |
| Nov | 3.35 | 2,663 | |
| Dec | 4.18 | 3,322 |
Mar is the wettest month (4.41 in, 3,505 gal off the roof); Feb the driest (3.00 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 Westbury
Best fit: one 55-gallon barrel, which delivers about 364 gallons to the garden in a normal year (78.7% 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 Westbury's roof water will pass straight through it.
| Tank | Water used (gal/yr) | Spills over (gal/yr) |
|---|---|---|
| 55 gal | 364 | 34,509 |
| 110 gal | 364 | 34,509 |
| 165 gal | 364 | 34,509 |
| 275 gal | 364 | 34,509 |
| 550 gal | 364 | 34,509 |
| 1,000 gal | 364 | 34,509 |
| 1,500 gal | 364 | 34,509 |
| 2,500 gal | 364 | 34,509 |
| 5,000 gal | 364 | 34,509 |
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 New York?
No statewide rainwater harvesting regulations; check county for local incentives
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