Harrison, NY rainwater: 37,952 gallons off a roof
Harrison, NY: gallons off the roof each year
37,952gallons a year
That is a 1,500 sq ft asphalt roof under Harrison, NY's normal 47.8 inches of rain, about 795 gallons for every inch that falls.
In Harrison, 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 Westchester Co Ap station (3.1 mi away). Harrison, NY ranks 36th wettest of the 90 cities covered in New York.
Month by month in Harrison
| Month | Rain (in) | Off the roof (gal) | Garden shortfall (gal) |
|---|---|---|---|
| Jan | 3.20 | 2,543 | |
| Feb | 2.53 | 2,011 | |
| Mar | 4.11 | 3,267 | |
| Apr | 4.20 | 3,338 | 19 |
| May | 3.94 | 3,132 | 51 |
| Jun | 4.25 | 3,378 | 12 |
| Jul | 4.07 | 3,235 | 35 |
| Aug | 4.36 | 3,465 | |
| Sep | 4.94 | 3,926 | |
| Oct | 4.33 | 3,442 | 2 |
| Nov | 3.64 | 2,893 | |
| Dec | 4.18 | 3,322 |
Sep is the wettest month (4.94 in, 3,926 gal off the roof); Feb the driest (2.53 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 Harrison
Best fit: one 55-gallon barrel, which delivers about 93 gallons to the garden in a normal year (77.7% 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 Harrison's roof water will pass straight through it.
| Tank | Water used (gal/yr) | Spills over (gal/yr) |
|---|---|---|
| 55 gal | 93 | 36,689 |
| 110 gal | 93 | 36,689 |
| 165 gal | 93 | 36,689 |
| 275 gal | 93 | 36,689 |
| 550 gal | 93 | 36,689 |
| 1,000 gal | 93 | 36,689 |
| 1,500 gal | 93 | 36,689 |
| 2,500 gal | 93 | 36,689 |
| 5,000 gal | 93 | 36,689 |
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