Originally posted by OneJasonBradly: Not requiring help just adding info. I have a workshop city with the same issue, sort of. I have 3 single spikes in my river. I too have Quay walls and these spikes all are in the area where the walls were used. I removed the walls, dug the river deeper, slightly and removed the ferry stops along this river and no change to these spiky things. The river bottom when I found it was smooth and well made, no obstructions were seen on the river floor or in any part of the river.
Edit; I did try to dredge the river with MoveIt to see if there were hidden objects but nothing was found.
I'm not entirely sure what causes it. I've had one in one of my cities, which was right where a canal opened up into a river. Moving the end of the canal around a bit and smoothing the terrain, then letting the spike drop down and the water get calm fixed it for me. So my best advice is just to keep trying to change it up a bit, smooth terrain, let the water calm, save, restart the game and see if it fixed it. I wish I had a better trick, but it seems like something fairly rare, so it's really hard to pinpoint what causes the glitch.
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