Increased water and urination

After Bofurs bout with stasis we changed up his diet- fresh salads twice a day, no pellets or treats (unless we're rewarding him for letting us pick him up) and we switched up his hay in hopes to get him to eat some and now that he's got orchard grass he eats it like a mad man (yay!)
However we've noticed that he has been drinking more water and there has been a marked increase in urine output-it was puddling on his newspaper and left his feet soaked so a litter switch to piddle pads happened. Urine doesn't look sludgy and is his average color, and poos are normal also.
Could it just be from his diet change? Because he's eating hay (I assume that might make them thirsty?)
Or because of the weather change perhaps?
Any thoughts/opinions would be much appreciated!

Same thing happened to Butter last week when I decreased the pellets in her diet and she started eating more hay and veggies. She was noticeably peeing and drinking at least twice the amount she normally does. I was worried so we called our vet and they told us that it is probably because of feeding her more hay. More hay = more fiber which requires more water. Veggies also have a lot of water content. As long as she's not peeing in different places, the vet said it's not a UTI. Just monitor your bunny carefully for any change in behavior that may indicate pain. But most likely your bunny is fine.