Land-based aquaculture would stress resources
Courier-IslanderNovember 12, 2010
After reading Ray Griggs recent opinion column, 'Land Based, Closed-Containment Salmon Farms', I wondered how this approach would look in the context of the salmon farming industry's current production. If, as Ray so boldly stated, this should be the future of salmon farming in BC, then we need to look at the whole picture.
Each Coho unit produces 100T of fish per year, using 400L of fresh water per minute, and the waste from each 200 kg produced could grow 3,000 heads of lettuce. All produced in 10 tanks, for the low cost of $1.2 million and the use of 210 million litres of water per year.
This equates to 168.192 billion litres of fresh water per year, and 22.5 million heads of lettuce to produce 80,000 tons of salmon in BC, using 8,000 tanks at a cost of $960 million.
Ray's proposal makes some very broad assumptions. He assumes that we will want to divert fresh water from our already overtaxed watersheds and that the public will want to see large tank installations placed close to our cities and rivers. It also assumes that the industry can stay competitive, given that the production costs will clearly increase.
Closed containment is not a new concept to the industry. Industry smolts are currently produced in land-based, closed systems. The need for fossil fuels to pump, circulate, heat and clean water, the land required to house installations - these would contribute to higher cost both environmentally, economically and socially to grow the same amount of food.
It's easy to throw out numbers and make bold claims, if you are willing to ignore that fact that BC salmon farmers grow high quality, low cost protein for a very low carbon footprint.
Tim Lelliott
