I have a 9 year old male cat (indoors) that seems to be drinking a lot more water than usual. Tonight I was watching him and he went to the water bowl about 4 times within an hour. Of couse all this water is making him visit the litter box more often as well. I noticed his increased water consumption a few weeks ago about the same time that I noticed a lot more lumps in the litter box. He seems to be fine otherwise. Is this cause for concern?