I have a gutter downspout about halfway through the lower section of a flat roof that currently connects to a rain barrel. The barrel is poor quality and sprung a leak that I have tried patching multiple times, and it's a bit of an eyesore. I'd like to cap the downspout and remove the rain barrel, but I'm not sure if this would put unnecessary load on the remaining gutter on that side of the house.
Is this something I can do without risking the water overflowing? I don't want to install a downspout there because of its inconvenient location that isn't on a corner.
Also, if I can cap it, how do you go about doing that? Would I just put a shingle over the downspout hole in the roof and seal it, or is there a more proper way?
See photos for more info.
I can't get up on the roof at the moment, but it looks something like the following photo with a round drain, but then a square cutout instead of a round cutout: