my garage sits on a downhill slope. water would flood into the garage whenever there is a heavy rainstorm. the flooding does not occur often as i live in ca. i want to create a small drain channel about 1 1/2" wide and 3/4" in depth in the concrete driveway to divert the water away by sawing and chipping the concrete. my worry is creating a drain channel will create unwanted cracks in my concrete driveway. my driveway is in a very good condition. will i create unwanted cracks if i create a drain channel? what are your thoughts?
i do not want to create 4" wide drain channel with metal grate.