yes there are 2 ways to do this
on the play testing screen when testing your level, you press tab and a large hud full of options happen one is water level you raise it to the level you want on for that level and save it and when building game it should be automatic to what was set. and the same for each level, you set each level individually.
the other option is through trigger zones and scripting which is simple once you grasped the basics of soundzones triggerzones etc. there are specific scripts for raising and lowering water levels this can change the water levels in that level when walking on a trigger zone.
hope this helps
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