The back of my garage roof does not have a gutter and rain, snow, etc. ponds on the paver walkway below AND when cold enough...freezes. I want to install a gutter but I have no where to route the downspout. No matter where I bring it down, it will be on a surface that is walked on and could freeze. I'm thinking about routing it underground. Has anybody done this? If I dig a hole and fill it with stone, etc., should this work to remove the water? Let it perc into the ground? Thanks in advance.