Fish farms want to be in the ocean to use them as a free, open sewer, that is all.
It will take you fifteen minutes to read this article and I suggest you do so, as it is a good one-stop take on PRV, HSMI, IHN, ISA, SLV, sea lice and so on.
The disease that I want to feature here - though it is not more serious than the others, far from it - is IHN, that has caused three epidemics in farmed fish over the last two decades. We have paid many millions of dollars to fish farms for their diseased, dead fish, so they can grow more and kill wild salmon. We don't want to pay. (See the indexes in the Feb 1, 2017 post on the most popular posts in Jan 2017, for the links).
Please note that one of these epidemics killed more than 12 million farmed salmon.
Here is some text from the article:
"IHNV is a rhabdovirus. Endemic to the Pacific Northwest, it has spread to Asia and Europe through movement of infected salmon eggs (OIE, 2009). IHNV is an internationally notifiable disease as per the World Organisation for Animal Health .
The IHN virus was first reported in BC Sockeye Salmon over 50 years ago, but was considered a freshwater disease . Detection of IHNV in seawater-phase Sockeye Salmon is uncommon . The virus is known to have a devastating impact on Sockeye Salmon , with greatest susceptibility occurring in juvenile salmon , OIE, 2009) where 50 – 95% mortality can occur  and .
Atlantic Salmon are acutely vulnerable to IHN and once infected, will carry higher IHN virus titres than Sockeye Salmon , which suggests Atlantic Salmon shed higher concentrations of IHNV than wild salmon. There have been three IHN outbreaks reported in the BC salmon farming industry  and  in 1992-6, 2001-3, and 2012."
"The 1992–1996 epizootic occurred in the Discovery Islands where it spread to 14 farms within an 11 km radius. The genetic homogeneity of the virus was specific to the farmed, but not the adjacent wild fish, and the outbreak ended abruptly with the onset of an area management plan suggesting that farm-to-farm transmission, not repeat infection from wild fish, sustained this outbreak ."
"The 2001–2003 epizootic also began with a single farm in the Discovery Islands. Genetic sequencing was used to trace the virus's spread to 32 salmon farms across the southern half of the BC coastline, including 81% of the farms in the Discovery Islands . In addition to farm-to-farm transmission, juvenile Atlantic Salmon became infected as they were transported through the Discovery Islands aboard a vessel pumping raw seawater through the fish holding tanks. Farms along the route of this vessel, off Port Hardy (Fig. 2), became infected, as did the receiving farms on the Central Coast and in the Broughton Archipelago, where the virus resumed its farm-to-farm spread."
And this stunner:
" reported that vaccinating farm salmon for IHN reduces downstream farm infection by only 31%, and that a vaccinated site will contaminate the entire width of Discovery Island waterways for over 30 km."
The article does not go on to list the same kind of information from the 2012 infection, but both Cermaq, in Clayoquot Sound and Grieg Seafood in the Powell River area had IHN in this infection, both of which were compensated for their diseased dead fish by us, the taxpayers of Canada, through the CFIA. Look at the Feb 1, 2017 Most Popular Posts of Jan 2017, for the indexes that will take you to the half dozen posts I have done, and their links for your follow-up, on the total payments for ISA we have made across Canada.
The total paid, just for ISA, is $177 Million that we taxpayers paid to foreign multi-national multi-billion dollar corporations, as well as some Canadian ones in Atlantic Canada.
We don't want to pay, so let's put fish farms on land or they can go back to Norway, where their own government is so fed up with their lice, diseases and sewage, it is giving out free licences to set up on land, a $9 to $12 million subsidy, based on the auction price for a saltwater licence. Note that the saltwater licences are so expensive because they are goldmines for an industry with a 23- to 25% profit margin.