Devastation on Fell ChannelAbout 3:30PM on Wednesday I received a report that the Fell Channel had dried up. I was on site within 30 minutes to check things out. Once on site it was evident that the Channel had been running dry for quite sometime. Perhaps a day or two. There was almost no standing water at all downstream of the Fell Hill trailhead. I was able to move about 6 Coho fry from the channel to the mainstem of Mosquito Creek. The fish were very lethargic and made no effort to evade my hands as I moved them into a water filled container. As I walked up the channel bed, I could see rat and bird footprints. Likely these were the first scavengers on site to clean up the fish that had fallen victim to no water. The ReasonThere were two factors that played into the drying of the channel. 1) The first was unusually low flows from all the extremely hot and dry weather we have been having this year. 2) The second was due to issues with the weir at the channels intake. The Lock Blocks used to help funnel water into the two intakes had sprung 3 leaks. At each Lock Block joint water was escaping through somewhat small holes, but the volume of water going through was too great to back up water behind the weir and steer the water over the two intake areas. The water needed to be raised about 8-12". The SolutionThe solution was to plugged/patch up those 3 leaks. On site all I had was a water bottle, I was able to scoop small rocks, gravel, and sand into the bottle and dump it into the holes. It was a slow process that took about an hour to start having an effect. Once that was completed I viewed the channel, and it was evident we now had water flowing down the channel once again. As I walked down the channel I noticed there was still no water downstream of the Fell Hill trailhead. Likely do to the small volume of newly fed water slowly filling in pools and being soaked up by the ground and the trees. After about an hour of trying to assess the damage and salvage more fry I noticed the water had finally made it down to the lowest reaches. My work had paid off. Further improvementsMy phone had died and I was exhausted. I decided to go home to hydrate and charge my phone. I went back to the creek better prepared with a shovel and pail, and continued to work on the weir. The job went much faster this time and after about 40 minutes of work and telling trailwakers what it was that I was doing I felt confident that the patch-job would hold. Further to this work, I have heard that Al will be on site tomorrow with a fabric that will be placed infront of the weir on the creekbed to hold rock, sand and gravel in place to prevent these holes from occuring in the future. The CostAlthough the fix was relatively quick, the cost to the creek is substantial. Largely due to the fact the channel habitat had been dried up for quite sometime.
I estimate that over 1,000 fish were lost and we only retained approximately 10-15% of the number that usually occupies this wonderful piece of habitat. It is quite devastating considering there were so many Coho fry utilizing this habitat after the spawning pair last fall.
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AuthorKeegan Casidy Archives
January 2020
CategoriesMosquito Creek,
North Vancouver, British Columbia |