RoofRainYield

Hopewell, VA rainwater: 39,796 gallons off a roof

Rainwater from a roof in Hopewell, VA

39,796gallons a year

That is a 1,500 sq ft asphalt roof under Hopewell, VA's normal 50.1 inches of rain, about 795 gallons for every inch that falls.

In Hopewell, VA 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 Hopewell station (1.3 mi away). Hopewell, VA ranks 6th wettest of the 39 cities covered in Virginia.

Month by month in Hopewell

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan3.532,806
Feb3.012,392
Mar4.023,195
Apr3.843,05264
May4.253,37812
Jun4.563,624
Jul5.184,117
Aug5.594,443
Sep5.154,093
Oct3.672,91785
Nov3.432,726
Dec3.843,052

Aug is the wettest month (5.59 in, 4,443 gal off the roof); Feb the driest (3.01 in). Garden shortfall is what a 200 sq ft vegetable bed needs beyond the rain that lands on it, April to October.

Barrel or cistern in Hopewell?

Best fit: one 55-gallon barrel, which delivers about 130 gallons to the garden in a normal year (80.8% 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 Hopewell's roof water will pass straight through it.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal13038,481
110 gal13038,481
165 gal13038,481
275 gal13038,481
550 gal13038,481
1,000 gal13038,481
1,500 gal13038,481
2,500 gal13038,481
5,000 gal13038,481

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 Virginia?

Legal and promoted by the state. Va. Code 32.1-248.2 directs the Board of Health to set standards for rainwater harvesting systems, and the Department of Health with DEQ to promote rainwater use. No state storage cap; indoor/potable use must meet health regulations.

Checked against the current source on 2026-11-06. Source