Mussel trouble for Shields ferry ( BBC )

Gavin Gait
19th February 2008, 21:24

19th February 2008, 22:16
Sounds familar LOL

J Boyde
20th February 2008, 09:17
Mussels, a real curse in the port of Mt Maunganui. Best way to clear them in those day any way, take the pipe out the fill it up with hot water. The engineroom will of course smell of cooked mussels. They start as spat, then grow.
Jim B

20th February 2008, 10:52
Mussel trouble for the Shields Ferry (BBC)

This news is reminiscent of a similar incident 50 years ago.

Our little ship “Navua” was on the Auckland to Pacific Islands’ bananas run and as she was a small vessel we were able to shut down the generators in port when not working cargo by plugging into the shore power supply. It became the habit to leave the small salt water sanitary supply pump running on shore power and overflowing the small header tank up near the funnel so that there was never a shortage of flushing water overnight and as a consequence of this practice the sea water suction valve was never closed. This same pump was capable of supplying water to the generator cooling water heat exchangers so it saw a lot of continuous service.

Came the time to sail one afternoon, the generator cooling had been on the main engine jackets for some time and when I switched back to the normal system there was a rapid rise in the generator jacket temperatures and alarms started to sound. No matter what we did we could not cool the generators so advice to the bridge about 30 minutes before cast off that we had trouble and we started to inspect the cooling system. It took five minutes to reveal the problem; there in the end of the heat exchanger sea water side was thousands of tiny dead mussel spat. Searching further we found small developed mussels in the immediate pipe work and within the hour the sailing was canceled. It got worse by the minute and eventually fully grown mussels were found in a large salt water cooling over-board discharge pipe.
Down came the Engineering Super, in came a specialist shore gang to carry out an acid clean/kill and red faced ship’s engineers all round.

It took a couple of days to clean up, working all hours but eventually we were away and not too late in picking up that next load of bananas. I can’t recall the disciplinary outcome, someone would have got a bollocking, but I do remember that the Department of fisheries sent a Marine Biologist on board to view the “breeding” ground and his main concern was to determine whether they were Auckland or Pacific Island mussels and to question us re water temperatures. His suggestion was that the young spat had relished the warmer tropical water and had migrated up into the larger pipe work as they grew but Auckland’s winter water temperature in July was too cold for the younger spat to adjust to and they died, lost adhesion and blocked the heat exchanger.
A good theory and maybe his research aided the eventual mussel farming industry that sprang up in NZ!

Gavin Gait
20th February 2008, 10:59
We used to suffer from mussels in the heat exchangers every summer in Aberdeen. The main engine on the David John was a 500hp Mirlees Blackstone ERS6MGR which was fresh water cooled through a heat exchanger and the salt water side of the system was always bad in July/August for clogging up when the mussels had grown large enough to restrict water flow. I've seen us with the deck hose supply ( donkey pump ) run through the heat exchanger to help cool the main engine ( we had piping in there permanently just for that ) and always ended up having to go up on the Pontoon dock to have the pipes cleared out.

20th February 2008, 11:58
I've had sea water piping so clogged with mussels, we had to dock the ship and take sw pipes and valves out. Turns you right off of farmed mussels for supper.
But the absolutely best story I ever heard was one the old steam engineer told me when I fisrt started. They had run through a fish spawning area-herring maybe, and the circ pump picked up fish. The first sign was the condesor ejector belching steam and the vacuum dropping rapidly, then the engine coming to a shuddering halt. The engineroom is rapidly filling with steam, so they opened the atmospheric valve, which now means boiler water is going to atmosphere.
They popped the end cover off the condensors and tons of cooked fish slid out into the bilge.
They got the plant up and running, but the smell of cooked then rotting fish was with them for days. (Whaaa)

21st February 2008, 12:17
Looks like muscle power doesn't work the way it used to(Jester)

Steve Woodward
21st February 2008, 12:29
You can always get your own back - Moules mariniere for lunch!

28th February 2008, 14:53
Best to kill them off early in the season while still just spawn before they mature,there by avoiding the problems later.Kenny.