Can drinking milk when lactose intolerance cause any damage?

Water is fine: Lactose intolerance is a deficiency in the intestines of lactase the enzyme that digests milk's sugar (lactose). Water does not contain lactose therefore not a problem.

Perspectives differ: From my perspective the problem creates bloating, cramping, loose acidic stools & peri-anal irritation. I consider that an inconvenience. It does not cause your gut to bleed or worrisome damage to the intestines.