[2022] Water Spikes @Dams

Using the landscaping smooth tool try smoothing out the terrain under where you see all the spikes (can do this while paused), then use the water tool from Extra Landscaping Tools to reset the water level a few times while the simulation runs to avoid too much flooding.

Once the water is all settled down, save the game (I recommend saving as a new file), restart it and load the new save. Hopefully the terrain deformations causing the water spikes is gone now.