RoofRainYield

Yonkers, NY rainwater: 40,726 gallons off a roof

Yonkers, NY: gallons off the roof each year

40,726gallons a year

That is a 1,500 sq ft asphalt roof under Yonkers, NY's normal 51.2 inches of rain, about 795 gallons for every inch that falls.

In Yonkers, 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 Dobbs Ferry-Ardsley station (4.6 mi away). Yonkers, NY ranks 4th wettest of the 90 cities covered in New York.

Month by month in Yonkers

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan3.873,076
Feb3.302,623
Mar4.373,473
Apr4.263,38611
May4.273,39410
Jun4.583,640
Jul4.533,600
Aug4.443,529
Sep4.613,664
Oct4.433,521
Nov3.883,084
Dec4.703,736

Dec is the wettest month (4.70 in, 3,736 gal off the roof); Feb the driest (3.30 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 Yonkers

Best fit: one 55-gallon barrel, which delivers about 16 gallons to the garden in a normal year (75.5% of its need).

If you buy one, a 55-gallon barrel with a downspout diverter is the whole job. Check that the overflow points away from your foundation, because most of Yonkers's roof water will pass straight through it.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal1639,525
110 gal1639,525
165 gal1639,525
275 gal1639,525
550 gal1639,525
1,000 gal1639,525
1,500 gal1639,525
2,500 gal1639,525
5,000 gal1639,525

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