M.G.
Lots of people go the water route. My nephew however then demanded to have bottles with water in them, so it kind of backfired. He also wet his diapers and kept my sister up all night.
I got rid of bottles after my first was one, much sooner with my others. I did the crying it out method with my first. I did the exact time increments they suggested. I did it word for word. It didn't take me many nights. I think maybe even 2. I hated it though.
With my others, I modified it. I went in when I could tell they were upset, and just acted like it was nothing, soothed them and when they had calmed I left again. But because I wasn't watching the clock and just doing what I was comfortable was, I was way calmer and less stressed, and my babies sensed that. I think my poor first born must have known I was a wreck. It was a pretty horrible experience.
If you find it easier to offer him a sippy cup with water just in case he's thirsty, you could try that. But ultimately if he's waking 3 times at night at his age, you are just going to have to carve out some nights and get through it. Good luck