10/14/2026
A 1,500 sq. ft. roof sheds roughly 935 gallons of water for every inch of rain. Split evenly across four downspouts, that’s about 230 gallons through each one over the course of that rainfall.
That’s why one sagging or clogged gutter run can matter more than it looks. The gutter has to carry the flow, and the downspouts need to keep up, especially during heavy rain and snowmelt here in Upstate NY.