I started smelling sewage in my basement bathroom, and when I looked in the toilet, it had no water in it(none on the floor) It was used the previous day. When I flushed it, it seemed to be normal and stay at the correct level. I came back and checked about a half hour later and still seemed fine.
What happened to my water??

Hey Brewski, Unless there's a crack in the bowl, in which case the bowl would be empty every morning, the only thing that would pull water from the trap and bowl is suction. Every time you flush or drain a fixture suction is set up in your drainage system. This suction is relieved by vent pipes through thr roof. If a vent's blocked the suction relieves itself by attempting to pull air through the nearest trapped fixture. In this case your toilet. I have found birds nests, dead critters and all kind of trash that blocks vents. Shine a light down the pipe that vents the basement group. If you can see nothing then you'll have to snake out the vent to clear it. Good luck, Tom