Any time one disturbs the clay liner there is a risk of creating a leak. Mike Otto runs into this often during rehab projects - if too much material is excavated from a silted in pond there exists a risk of exposing suspect material which exists below the liner. I agree it's safer to opt for a floating dock, and they are easier to install.

Corey ran into this issue when he installed his dock and had to apply polymer in that area to treat the leaking areas around his pilings. I wouldn't personally risk it.

Many men go fishing all of their lives without knowing that it is not fish they are after. ~ Henry David Thoreau

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