The following letter is my response a letter Brian Hayden posted on the Tideline on May 19th. It is an excerpt from an interview I did with the Cortes Currents and that article also includes interviews with Brian Hayden and a Mosaic rep. https://cortescurrents.ca/the-environmental-impact-of-an-active-log-dump-in-gorge-harbour/
I have been diving to checking moorings and dock lines in the Gorge for 30 years, diving both the east and west ends and under the Bee Islets shellfish farm.
My direct observations is that the bottom is clean rock or sand to a depth of 15-20m and then the bottom is mud and sand. Under shellfish rafts, the bottom is a matrix of sediments mixed with oyster shell and lost plastics. The shellfish rafts themselves provide a substrate in the water column for fish and invertebrates to find habitat in. It is a diverse vibrant community, to my eyes quite beautiful and you can see it for yourself from this video I took. The Gorge Harbour Oyster Farm Dive Https://www.youtube.com/watch?v=ZLumyWyG3nA&t=28s
At Mosaicís Cortes Island ZOOM meeting, last January, I commented that about 15 years ago I had observed a thick layer of wood debris and sediments, covered by Ďbacterial matsí directly under the log dump. I suggested that any disturbance of the sediments could pollute nearby shellfish operations.†
The response from Mosaicís Colin Koszman was that their marine biologists had checked it out and said, itís all fine. I donít know if that meant actually taking samples from the bottom and seeing what contaminants and toxins are in those sediments though. Bark and wood debris leach toxins that have been studied and are known to be toxic to salmonoids.
The study from 1977 that Brian Hayden refers to in his letter, was done during the hey-day of industrial logging on the island and although I have not gone out to source archival history, I can well imagine the protected waters of the Gorge was an ideal booming area where logs would be tied up on both the east end and the west end, waiting weather and awaiting enough volume so that they could be towed out in the entrance and down south to the sawmills and pulp mills. I can also imagine that there was a lot more impact on the up shore areas of the Gorge due to logging. And there would very likely have been quite a bit of sedimentation coming down from† those logging areas surrounding the Gorge.
I would also like to add that the Gorge is not the only area where that heavy muck and aerobic muck with the bacterial mats occurs. That is what the bottom of Cortes Bay is. Thatís also what a lot of Squirrel Cove looks like and (decades ago) there were big booming operations in Squirrel Cove. I have to untangle anchors from sunken logs in Squirrel Cove quite regularly, and that is a really low viscosity stinky muck thatís covered in bacterial mats. I suspect that any enclosed bay with low flushing action in the Discovery Islands where there were logging and booming operations will have a similar situation.
The Gorge has a strong tidal flushing action though. Life flourishes there; in the shellfish rafts and beach leases. Down deep, anywhere a boulder or object protrudes above the mud, it will have anemones, sea stars and shrimp living on it. Earlier this spring, I dove to the bottom, to check some moorings by the big barge thatís anchored just off the log dump.† I was happily surprised to see that the bottom was very alive and it was a bouldery bottom with lots of growth on it.
I have also dove around some docks and their moorings in the immediate neighbourhood and found that the bottom is clean. Shortly after the log dumping operations by Klahoose and the Community Forest Partnership happened, I asked both Island Sea Farms and some of the local residents if they had noticed turbidity in the water, and they said they hadnít really noticed any difference at all.
But this spring, there was not a lot of volume of logs that went down the log dump. Mosaicís proposed logging activities would see much more log dumping with the associated risk of disturbing the sediments that remain under the log dump.
I think instead of sitting on the beach and wondering and worrying about whatís happening below the water, it would be very good if an actual dive study was commissioned with divers mapping and identifying the anaerobic zone underneath the log dump†as a baseline and then studying the effects of log dumping later on. There just hasnít been enough logs entering the water to stir that mucky stuff up yet.
Thanks for keeping your eye on this Brian!