New York, NY rainwater: 37,459 gallons off a roof
New York, NY: gallons off the roof each year
37,459gallons a year
That is a 1,500 sq ft asphalt roof under New York, NY's normal 47.1 inches of rain, about 795 gallons for every inch that falls.
In New York, 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 Ny Ave V Brooklyn station (5.2 mi away). New York, NY ranks 45th wettest of the 90 cities covered in New York.
Month by month in New York
| Month | Rain (in) | Off the roof (gal) | Garden shortfall (gal) |
|---|---|---|---|
| Jan | 3.53 | 2,806 | |
| Feb | 2.97 | 2,361 | |
| Mar | 4.37 | 3,473 | |
| Apr | 3.85 | 3,060 | 62 |
| May | 4.03 | 3,203 | 40 |
| Jun | 4.44 | 3,529 | |
| Jul | 4.85 | 3,855 | |
| Aug | 3.92 | 3,116 | 54 |
| Sep | 3.92 | 3,116 | 54 |
| Oct | 4.02 | 3,195 | 41 |
| Nov | 3.23 | 2,567 | |
| Dec | 4.00 | 3,179 |
Jul is the wettest month (4.85 in, 3,855 gal off the roof); Feb the driest (2.97 in). Garden shortfall is what a 200 sq ft vegetable bed needs beyond the rain that lands on it, April to October.
What size rain barrel for New York
Best fit: one 55-gallon barrel, which delivers about 200 gallons to the garden in a normal year (79.8% 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 New York's roof water will pass straight through it.
| Tank | Water used (gal/yr) | Spills over (gal/yr) |
|---|---|---|
| 55 gal | 200 | 36,089 |
| 110 gal | 200 | 36,089 |
| 165 gal | 200 | 36,089 |
| 275 gal | 200 | 36,089 |
| 550 gal | 200 | 36,089 |
| 1,000 gal | 200 | 36,089 |
| 1,500 gal | 200 | 36,089 |
| 2,500 gal | 200 | 36,089 |
| 5,000 gal | 200 | 36,089 |
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