Based on the title of this stage, it was exactly what I expected to see here, a watery and rainy themed stage with a tint of Toad Man which is present by the music choice.
The rain and rock dropper gimmicks fits well together for the construction site theme that this stage has gone for, the stage has a damp feel to it as plenty of it is during the rain where the player is forced to perform jumps that are normally impossible, and these feel super satisfying to pull off.
The rain also has similar effects in reverse by pushing the player back in some areas and being an obstacle, personally I prefer the sections which the rain favors the player and makes you be able to jump much farther than normally possible.
The structure and design is coherent as the stage flows well together, although the stage doesn't do anything groundbreaking or bad with its design, its passable but may not be specifically memorable for the concept it has chosen here.
The boss choice is thematically fitting, and I appreciate the thought of trying to spice up a vanilla boss battle, however it doesn't really work here since Toad Man is beatable without jumping which completely defeats the purpose of the rain present in his battle.
Overall, this is a fine stage which flows well together, using already tried gimmicks and puts them to good use, however the stage doesn't do anything groundbreaking which would be novel, so the stage is certainly passable and playable, but its not one that's going to be extremely memorable among so many other submissions.