$15M is quite a lot of money to be spending on construction. Let's look at the cost of moving the ship to a dry dock on the river every 5 years for the bottom to be washed and painted. I doubt that it would cost more than $1M each time. $15M would cover 75 years of maintenance, and that's not even counting interest costs on the $15M that would need to be borrowed for the cofferdam. Sounds like someone with a financial interest in marine construction is behind this push.
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