I built a roof over part of my deck. The roof has the solar water heater panels on it. Because of the location and wanting it to pick up the sun for longer in the day it is pitched towards the pool. The roof material is solid surface - not shingles, so I won't get any gravel washing off the roof. I am wondering if I need to bother with a gutter. Is there going to be that much crud washing off the roof? If I don't have a gutter, water would be draining into the pool. If it matters, the roof is 20' long x 5' wide.