Most municipalities outlaw the emptying of surface water into the sewer system. The reason being then that water has to be processed through the complicated and costly treatment plant. Also the huge volume involved with a downpour rainstorm or a long protracted rain, simply overwhelms the system, sometimes directly causing the total overflow of the treatment plants holding/processing tanks. Here is the real trouble starts, untreated human waste goes into the river or lake that normally only has treated water placed into it.
The roof leader, the pipe moving the storm/rain water should be contained in a pipe and let to drain onto your lawn or into a buried dry well or if your town has a separate municipal storm water system with street manhole, slope the ground so the water can flow to that manhole/storm catch basin.
The roof leader, the pipe moving the storm/rain water should be contained in a pipe and let to drain onto your lawn or into a buried dry well or if your town has a separate municipal storm water system with street manhole, slope the ground so the water can flow to that manhole/storm catch basin.