3 in. Corrugated Drainage Pipe
3 in. corrugated pipe is very easy to install so it’s a favorite of the DIYer. It can also provide higher velocity for downspouts. You’ll have a higher water pressure which prevents clogging.
Note: You can run up to two downspouts on a 3 in. line. Once you get to the third downspout, you want to tie it into a 4 in. main.