FF,
This happened in the summer of 2016, the marina was in SC and has since (fortunately) changed ownership. The Coast Guard & EPA slapped them very hard with fines. 34 boats (all diesels) were affected including mine, with varying levels of damage ranging from simply changing the Racors and polishing the fuel, to the complete loss of a 60ft Viking offshore. No one lost their lives thanks greatly to the CG SAR and to the use of an EPIRB and PLB's (If you don't have them, get 'em! They're the cheapest life insurance you'll ever get.).
I'm out $8k-$9k so far in repairs, and I haven't fixed/replaced the risers yet (2 sets of injectors, 2 fuel pumps, 3 alternators, batteries, 2 cracked risers, exhaust hoses, the list goes on.) and I'm still not back in the water. Hopefully this summer.
When the water/fuel hit the rubber exhaust hoses, the steam melted them enough to burn 2"-3" holes in them, which pumped ~12" of water in the bilge in less than 10 minutes. We actually "settled" on the mud before we could stop the leak. (Electrical tape over the holes!) The Genset allowed me to use the emergency sump to pump us out. With a a 2" hose it still took 2 hours to get us refloated. The port engine got us into Anchor Marina (good folx), which was about 30 miles from where we had gotten 180G of fuel of which 26G was water. (There's a clue)
The cause was that the fuel was gravity fed from the tank to the dock pump. The fuel lines drooped into the river. When the dock pump was turned on, it would suck water into the fuel line through some bad (plastic) pipe joints. If the pump wasn't running, the fuel wasn't going into the river, so no fuel spill. We never smelled a fuel leak.
The lawsuits are still pending so I can't name names.
Most folx have told me that She's not worth repairing. Monetarily that's true, but I don't plan on retiring for another 10 years so I can take my time in fixing her. Pretty much everything will need to be fixed, the plywood flooring delaminated, the plumbing and wiring are original, and have gotten soaked by saltwater (Corrosion in going to be a huge problem) so those will need to be replaced, I want to add propane, Stainless tanks (4 Fuel, 2 water, 2 waste), new swim platform, railings, hard Bimini, hoist, radar arch, dive compressor, Bow thruster, etc, etc, etc.
I found an (reasonably) inexpensive DIY yard that is close to work & knows that I'm gonna be there for quite a while. I'll have them do all the fiberglass work because I do well & truely suck at it. I can do the electrical, carpentry, plumbing & gas (Master, Master & Journeyman levels). My son is a Journeymen welder, so he gets tapped to do the welding (all SS) that I can't do.