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Home arrow Archives   The American Surveyor     

The Final Voyage—Part 2 Print E-mail
Written by Eric Stahlke, PS   
Saturday, 15 August 2015

A 3.760Mb PDF of this article as it appeared in the magazine—complete with images—is available by clicking HERE

The first day on the river in the Seloohge never fails to be memorable. This is because one of the worst stretches for navigation we expect to see all summer is located on the Tanana River only miles below Fairbanks. It's a 2500 mile marathon with Heartbreak Hill at the beginning.

Unlike a runner's marathon there is no possibility for practice. With the Seloohge everything had better work the first time. A dozen laps around our little mooring pond are all we get. By then the crew is beat up from a week of shopping, packing, loading and fixing.

But at least we're ready. The plan is an ever hopeful one: arrive at the dock early, load up, leave before noon with plenty of time available to deal with situations, all on a warm sunny day. The reality is always the opposite: lots of situations, late afternoon departure, usually in the rain. When most people are heading home from work, anticipating cold beer, dinner and TV, we're just entering the river.

Entering the Tanana River at spring flood with a 20 ton barge is no stroll in the park. It's a given that something bad will happen. On our most recent voyage, a 1500 mile trip to Fort Yukon and back, the nightmare of the first day was so dreadful that we promised to never speak of it again...and we haven't. May that memory rest in peace.

But it won't, our destiny is déjà vu all over again.

This time out our crew consisted of the usual mix of grizzled old-school surveyors blended with an equal number of innocent and hopeful newbies. Myself, as survey manager, our chief of parties Albert Macica, party chief Todd Jantzi and survey tech Alvin Dayton filled the former roll. We had been together since the mid nineties and shouldered the burden of experience.

Party chief Frank McGuire, survey techs Elisabeth (Bethi) Folger and Peter Flynn, as well as our new cook, Jeff, filled out the roster. The helicopter pilot would join us later. Bethi had traveled with us to Fort Yukon in 2009 as an apprentice, so she had an inkling of what the evening would bring.

The first 10 miles, in typical calm before the storm fashion, was along the lazy Chena River as it meandered its way out of Fairbanks. We followed behind Capt. Jim Jr. who was piloting the giant sternwheeler Discovery with 300 tourists on board. To keep his business afloat on an increasingly shallow and silt filled river, the Corps of Engineers had dredged out a new channel about ten years earlier. Since the channel was only wide enough for the Discovery we tagged along behind and patiently listened to their onboard PA system describing the wonders of Fairbanks. The tourists in the stern of the boat pointed and looked at us with puzzlement. Since the Seloohge wasn't included in the well rehearsed script the MC improvised: "If you fix your gaze to the rear of the Discovery you will see a fully loaded camp barge traveling behind us. This is a group of local scientists from the University of Alaska, setting off to explore the Arctic for the summer." Everybody waved, we waved back.

Back in the day the Discovery used to venture out of the Chena and enter the Tanana River to give the tourists a taste of a big glacial river for a minute or two. Then it would spin around and head safely back to port. Unfortunately, another Corps of Engineers undertaking, the Chena Flood Control Project, confined the Tanana in such a way that it may have been a factor in a recent avulsion. In 2011 the Tanana River retreated from its historical confluence with the Chena. The abandoned channel soon silted in, flushed only by the weak flow of the diminutive Chena. The new confluence with the Tanana is now located 5 miles farther downriver.

Needless to say the Discovery does not venture into the vast mud flat resulting from the avulsion. No such luck for us. I nosed the Seloohge into a bank and we waited while Albert and Todd in the pilot boat probed the flats with a stick for some sign of a channel. They eventually were able to mark out a sinuous route with buoys, barely wide enough for the Seloohge. "Don't veer off course," radioed Albert, "it's only foot deep mud at the edges..."

Unlike an automobile, a boat needs a certain amount of speed to maneuver. Rudders don't work unless there is a flow of water. The faster the flow the easier it is to turn. I was contemplating this fact as we rounded the corner and caught site of the slalom of buoys laid out by the pilots. No problem for a canoe or motorboat, not so great for a barge. We gingerly entered the course at idle speed, too slow for steering, and let the current float us along, using alternating forward and reverse thrust on the two engines to keep our alignment and nudge the boat into place. Thankfully the wind had died down and didn't push us into the mud.

The Chena's snail's pace through the mudflats was frustratingly slow but the doldrums ended in dramatic fashion at the site of the new confluence. Here the Tanana, a large and swift glacial river, pushed full force against a rock cliff at the exact spot where the little Chena feebly entered the channel, not allowing us any room to escape the current and run the inside curve. I turned the Seloohge upriver and gunned the engines the moment we entered but the current spun us around like a top and the boat just missed scraping the rocks. Besides the adrenaline rush, this was also the first little hint that all was not right with our steering system.

The second hint came an hour later as we were holding for the pilot boat to scout a bad crossing up ahead. We hold position by simply turning the boat upriver into the current and adjusting the engine thrust to match the speed of the river. Sounds easy, but with the trimaran configuration of the hulls the Seloohge becomes vulnerable to spinning with any slight misalignment. If the oncoming current catches an outboard hull at an angle there is a lot of rotational force generated and the boat wants to flip around. This is corrected by continually responding at the helm to offset the lateral forces; generally a half turn with the wheel is all it takes to straighten out.

The channel here was narrow and we were positioned near the outside of a cut bank curve, sitting in the only deep water available, when a developing whirlpool spun us hard to the right. I compensated with a turn to the left but nothing happened; instead we continued to spin into the bank. Not a problem had there been more room to maneuver, but here erosion was undermining the bank creating a long row of giant spruce sweepers that leaned far out into the current. There was no room available to ride out the spin. It took a desperation maneuver using full engine power with the wheel at the stops before the engines pushed us around to the left and corrected the spin. We just missed getting speared by a spruce pole.

In hindsight we should have pulled up then and there and performed a full inspection of the steering system before continuing down river. But we didn't.

A short time later the Seloohge was in a long holding pattern once again, at the top of Whiskey Island, waiting for Albert and crew to scout the next channel in the pilot boat. My ninety minute shift at the helm was up so Todd and I swapped out. No doubt Todd wasn't too pleased with the timing because Whiskey Island is near the top of our list of bad places. The island, shaped like a profile of T Rex, is several miles long and surrounded by a tangled mess of braided channels that snake through a minefield of spruce snags. The water current passing through the obstacle is also terrifyingly swift. Whiskey Island is the main reason that commercial barges don't even try to make it to Fairbanks.

By the time Albert, Bethi and Alvin returned with the scouting report the sky had darkened considerably and the rain was getting worse. Albert sounded weary on the radio, "Hate to say it, but Hot Slough is closed, there is no choice except to take the long way around. Good news is that it's not too serious except for that spot where the slough diverges. Bad news is that for a short ways it's gonna be really tricky... but there is no other option. Follow me closely and head straight for the three big spruce snags, maybe a little to the right because the channel is narrow above there...keep going straight until you're about 100 feet above the snags, then angle left to get around, staying as close as you can without hitting them...then, the second you're past them, hard right till you're on line below the snags, then straighten out...whatever you do, don't get too far to port...there is gigantic underwater stump on that side that you won't be able to see." We didn't say anything, so Albert continued, "You should be able to squeeze through..."

I headed upstairs to spot for Todd while he navigated closely behind Albert and crew in the pilot boat. When the three spruce snags came into view everybody on board gulped. Visualize 24 inch diameter logs, vigorously bobbing up and down in the rapids, about 40 feet of their length exposed above water, stripped bare of their limbs and bark by the Tanana current, and pointed straight at us at a sharp angle. They looked like gnashing teeth ready to chew us into toothpicks. Todd headed straight for them as Albert had directed, then he cranked the wheel to the left for the turn. Nothing happened. Unbelievably the Seloohge continued directly towards the hazard ahead. Todd spun the wheel farther to the left, all the way to the stops...and still nothing. We watched in disbelief. Though an empty gesture, and not likely to change the laws of physics, everyone on board was now screaming "TURN!!!" at the top of their lungs. Like a barrel approaching the lip of Niagara Falls, the Seloohge forged straight ahead. With a second or two remaining we braced for the collision.

Eric Stahlke, PS, was survey manager of Tanana Chiefs Conference Cadastral Survey Program from 1993 to 2014. He is now retired and living in eastern Oregon.

A 3.760Mb PDF of this article as it appeared in the magazine—complete with images—is available by clicking HERE

 
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