A few miles North of the Octopus Islands are the Okisollo Rapids where the northern shore of Quadra Island pushes up against Sonora Island, and the channel makes a sharp west turn before merging with the Johnstone Strait. My guidebook did not mince words about this treacherous stretch of water, and I felt the author was wagging his finger at me, lest I should underestimate what lay ahead. “Exercise extreme caution when crossing the rapids. You may run into violent rips, foaming overfalls, and gigantic whirlpools. Be aware of the tides and the winds and be especially careful with the Hole in the Wall gap between Maurealle and Sonora Island.”
He put the fear of Poseidon in me, and if I had a horse to sacrifice to the Earthshaker in exchange for a safe passage I would have done it.
I unfolded the Marla’s tide tables and looked up the table for the Okisollo Channel. The tide would start ebbing in the morning, reaching peak flow at 11:00am. The Hole in the Wall had a similar timetable, but she had added a note that drew my attention. It said, “The tide floods to the Northeast, and ebbs to the Southwest.” This was good, as there would be no risk of being sucked into the maelstrom with the ebbing tide.
When my engineer brain read the note and I was reminded of the Hardy-Cross problem from hydraulics class in university. My professor loved using the Hardy-Cross to assess who paid attention in class and who was asleep, and the midterm exam was one single Hardy-Cross evaluation. The problem set up is a a pipe network where the nodes have certain flow inputs or outputs, and the pipe segments have different lengths, diameters, and friction factors. The goal of the problem is to solve the flow magnitude and direction through all the pipe segments in the network. It is extremely difficult to solve by hand. The problem requires an initial guess for the flows through the network, which then must be iteratively adjusted with several calculation cycles to eventually converge on the answer. You know you are solving the problem correctly when the formula requires smaller adjustments with every cycle, but it is very common to make a mistake like a typo on your calculator, and the numbers never converge. “Think of it as a magic trick you do at the bar to impress the girls,” my professor would joke in class. “When you do the magic trick flawlessly you get laid. If you solve a Hardy-Cross on your job interview, you’ll get the job.”
Anyways, the reason why the note reminded me of the Hardy-Cross, was because I looked at the map of the channels around Quadra Island, and the maze of interconnecting channels looked to me like a pipe network; every channel has a different length and unique cross section, and every point where two or more channels meet is like a node in the network. When the tide moves the water through the labyrinth, the same family of hydraulic formulas can be used to solve the flow through the system. Of course, however, you would need to be a hydraulic savant to work it all by hand, but a sufficiently powerful computational fluid dynamics model would certainly do it.
I checked the time while I lay inside my warm sleeping bag. It was 5:30 am. “I better get moving or I’ll be crossing the rapids in the peak of the current,” I thought.
After a quick breakfast of canned tuna and a few spoon scoops of Nutella (not on the same scoop), I packed up camp and pushed off into the water to continue northward. There was no goodbye from my Toronto island mates ; judging from the loud snoring in one of their tents, they were all sleeping like rocks.
The ebbing tide quickly carried me, and I soon reached the head of the Okisollo Rapids. At first everything seemed calm, the water was flat, and there was no sound from the churning rapids. Even so I glanced at my GPS, and it indicated that I was moving at seven miles per hour, without paddling.
“No way, this thing has to be malfunctioning,” I thought.
I decided to run a test. I turned around and began paddling against the current. Soon enough the speed began dropping the harder I paddled, but never below three three miles per hour.
The rapids did not disappoint. Beyond the entrance to the Hole in the Wall the channel formed the largest whirlpool I have ever seen. The width was at least twice the length of my kayak, the eye dropped more than two feet, and it made ominous gurgling sounds like a drunkard at a bar chugging down a pint of beer. Fortunately, I saw it far enough ahead to avoid it. Like the drunkard in a bar, it’s best to observe this curiosity from a safe distance, and not provoke it into a fight with you.
Beyond the whirlpool the conditions were not so treacherous. The current hadn’t yet sped up enough to steepen the standing waves to the point of breaking, and I rolled over them like a water slide. In another half hour, however, things could be very different, and I would not want to be testing my surfing skills in a boat laden with gear.
The Okisollo Channel emptied into the Discovery Passage which as it flows north of the Seymour Narrows becomes the Johnstone Strait. The wider width of the channel in this area meant the current lessened considerably, and I had an easy paddle to a lighthouse called Chatham Point when the channel makes a sharp bend west.
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I stopped to look around, walked up a steep boardwalk from the mooring pier and eventually arrived in a grassy field with three white houses with bright red roofs and a helicopter pad. Someone was living here full time. One of the houses had a manicured flower bed of lupins in full bloom which must be the pride of the gardener who tended to it. Beyond the houses the grass field gave way to a gravel road where a red dodge ram pickup truck was parked. The truck engine was humming, but mysteriously I never saw anyone. I wanted to continue walking up the road to see if it led to some viewpoint of the channel, but I hesitated. The current on a concrete piling just off the cliff showed that the tide had turned, and I had not pulled my boat very far off the water to afford the time to explore.
I began walking my way back, and only made a stop at the lighthouse foghorn which had a sign that caught my eye. It said, “Stay at least 50 feet away. Risk of hearing loss.” Ironically, the sign wasn’t very big, and you might need to be closer than 50 feet to read it. Fortunately, visibility today was as far as the mountains would let you see, and I doubt the foghorn would be going off anytime soon.
Once the tide starts rising, it can really sneak up on you quickly. I was only gone for maybe 20 minutes, but when I had returned to the kayak, the water had already fishtailed. Another five minutes, and I would have been swimming after it.
As I continued paddling west against the now flooding tide the headwind picked up. I began to notice that although I was putting considerable effort, I seemed to be stuck on a treadmill. I edged closer to the north shore where there was a chain of islands and the eddies allowed me to hop along in a slow but steady progress. Once I reached the last island on the chain, however, there was nowhere else to go. I pulled out my phone and looked to see where the closest place to camp might be.
Sea kayak Vancouver Island Circumnavigation
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