Working on the old Port of Tacoma pier pilings last month

We were doing a standard inspection dive, about 25 feet down, and I noticed the concrete on the pilings was way more eaten away than the last survey from 2018 showed. It wasn't just general wear, it looked like something was actively boring into it in specific spots. We're talking holes the size of a fist in areas that were solid five years ago. My dive partner thought it might be a new type of gribble or shipworm moving into the area. Has anyone else run into accelerated piling damage in the Puget Sound recently, and what did you log it as?

2 comments

2 Comments

the_joel12d ago

You said it looked like something was actively boring into it, but that's a huge jump. Concrete decay is a normal chemical process, especially in salt water. A survey from five years ago is a long time, and you were probably just looking at different spots. Calling it a new pest is a stretch without lab tests to prove it.

tara_williams112d ago

Remember my friend who works on the old docks up north? He showed me a piling last year that was smooth as a dinner plate in 2018. By last summer it was covered in these perfect little holes, like someone went at it with a drill. The salt water decay he sees looks totally different, more like crumbling. He said it felt like watching something eat. That's what made me worry.