Outdoors/Adventure

Winds and tides can concoct a deadly brew in Alaska's Turnagain Arm

The wind was blowing hard the day Capt. Joseph Hugh Eros made his last, fatal trip to Fire Island off the coast of Anchorage. Twenty miles back down Turnagain Arm to the southeast, an automated anemometer at McHugh Creek recorded gusts in excess of 40 mph. Little did Eros know that it might mean the difference between life and death.

A 42-year-old judge advocate general (JAG) with the U.S. Army, Eros was no stranger to the forested, 5-mile-long island that juts out of the mudflats about 3.5 miles off the end of the busy airstrip at Ted Stevens International Airport in Alaska's largest city.

Low tides put the island within easy walking distance and friends says Eros had safely hiked there and back at least five times before his June 23 death. Tim Kelley, an Alaska adventurer who sometimes commercial fishes off the island, has a photograph of Eros standing next to a massive, gray rock on the island's northern shore.

The rock is a landmark for those hiking across the mudflats from Kincaid Park on the mainland almost due east. The photo was taken on Independence Day 2012.

It shows a fit, middle-age man in a "NIKE" T-shirt, some jeans shorts and soiled running shoes. A baseball cap is perched on his head. A pair of binoculars on a strap are across his chest. His legs are muddy up past his knees. But he appears not to care. He is smiling for the camera.

Behind him the bluffs of Anchorage rise to meet a sky capped by big, puffy clouds. Eros was one of a number of people crossing to the island that July 4 when tides just happened to be ideal for the adventure. Kelley remembers hiking a good part of the way with Eros.

"...He seemed like a nice and smart guy," Kelley said. "He was a person anyone would easily like.''

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'Follows tides meticulously'

Friend Lindsey Fees remembers Eros as both likable and cautious. She journeyed toward the island with him less than a month before his death.

"He followed the tides meticulously," she said. "He carried rope in case someone got stuck. He wouldn't let us separate. I was pokey and we didn't make it all the way to the island.

"He checked his watch constantly and had us head back before getting to the island, so we could safely return before the tide did. When we went, on May 27, low tide was around 4:30 p.m. and we returned to Kincaid two hours later -- right about 6:30 p.m. There wasn't enough water to swim in if we'd wanted to. The most water we encountered was in the middle of the mud flats and it was calf height."

Things were much different a month later.

Ivy League swimmers

It was about two hours after low tide on June 23 when a 911 call was placed reporting two men swimming for their lives in a tidal river off Kincaid. Anchorage attorney Michal Stryszak, a former member of the Yale swim team, would safely reach the beach. Eros, a graduate of rival Ivy League school Harvard would not. His body would later be found offshore.

"(A) witness said the men were heading to Kincaid and were a third to half of the way from Fire Island when the men had to cross a channel of incoming water," reported Megan Peters, a spokeswoman for Alaska State Troopers. "The water was deep and required them to swim across it. During the swim across this channel is when things went bad.

"One needs to keep in mind the channels in the Arm change day to day."

Only the channels don't really change day to day. The channel -- more of a gut actually -- in which formed a tidal river blocking Eros and Stryszak from the Kincaid beach on June 23 has been there for years. It has not moved much. It shows up on maps dating back to at least 1985.

Other channels in Turnagain Arm do regularly shift and move, but only by force of nature and after the shifting of vast quantities of sand and silt.

Water is different. Water is always moving.

Tidal predictions difficult

The U.S. National Oceanic and Atmospheric Administration (NOAA), which compiles tide charts for U.S. waters, warns that tides are sometimes hard to predict with complete accuracy. There are a variety of factors that can affect both the timing and the height of tides.

Among them: the shape of the coast, the depth of the water, seafloor topography, weather, air pressure and the wind. How much these will alter the predicted tides from their predicted heights and times depends to some degree on how far one is from a tide-tracking station.

"Because of the numerous uncertain and, in some cases, completely unknown factors of local control mentioned above," NOAA notes on its website, "it is not feasible to predict tides purely from a knowledge of the positions and movements of the moon and sun obtained from astronomical tables. A partially empirical approach based upon actual observations of tides in many areas over an extended period of time is necessary. To achieve maximum accuracy in prediction, a series of tidal observations at one location ranging over at least a full 18.6-year tidal cycle is required. Within this period, all significant astronomical modifications of tides will occur."

Matt Forney, the NOAA tide monitor for the Port of Anchorage, said the tides for the port near downtown are very accurate. The government, he said, has been monitoring them for 18 years, and the tidal predictions are built around that monitoring.

Move away from the port, however, and things begin to change. Generally, the tides in the Cook Inlet shipping channel west of the port and north of Fire Island are about 20 minutes off from those in Anchorage, and they are pretty predictable, said Peter Stewart, who managed the installation of the Fire Island wind farm for the Anchorage-based Native regional corporation CIRI.

Part of that project involved laying a submarine cable between the island and Anchorage. Stewart spent a lot of time on the water off Fire Island when the tide was in and a lot of time on the mud when the tide was out.

Fickle tides

Over that time, he discovered just how fickle tides can be. Regular though they might be north of the island, things can change to the south where there are huge, shallow shoals.

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"What is deceptive, and I've seen it so many times," Stewart said, "is that it's like a bath tub filling up. When you fill up the Inlet, you don't see a lot happening until you hit the rim, and then everything spills over."

Once this water gets out of the Cook Inlet-Knik Arm channel, he said, "it moves across the (Turnagain) flats at walking pace," and gravitates toward low spots where tidal rivers begin to form.

"It's incredibly deceptive," he said. "One of the most awkward drainages is the first one from the mainland."

It would be this drainage that cost Eros his life. It is not "a third to half of the way" between Fire Island and the mainland, as Peters relayed, but more like a quarter mile off the Anchorage coast -- deceptively close to the safety of the Kincaid beach.

Unfortunately, Stewart said, if someone arrives at this point with the tide starting to flood the gut from the north, "you have a river to cross. I don't think people realize how strong that current can be along that thing."

'Worst experience of my life'

Stryszak knows, however.

"The water was moving fast," he said in a series of email exchanges. "I can't tell you for sure that the current was running from north to south in that last channel. But two facts I do know support that conclusion. The woman who waded in to try to help us did say that we were swimming at an angle to the south:

Because we were attempting to swim directly across, a strong current north to south would explain why we were swimming at an angle to the south. In addition, before we hit that last channel there was a relative flat large area where a mini bore tide was moving from north to south. It was moving at about the speed of a person walking. The water was only about an inch deep before the tide and about 2 inches deep after the tide moved through.

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This has been the worst experience of my life. But I should consider myself very lucky that I didn't get pushed farther south on the beach, where it makes the 90-degree bend and opens toward Potter (Marsh).

Getting pushed south, however, might not have been so bad. Smith noted that "if you were farther south toward the (Campbell) point, it definitely shallows out."

Beyond Campbell Point, there is a vast flat of firm, compacted sand that stretches for miles and miles offshore. Had Eros and Stryszak washed up there, they would likely have been able to wade to shore.

Fighting the current and the 57-degree water to get across the gut farther to the north, on the other hand, consumed precious energy. Lindsey said she believed Eros to be a descent swimmer, but the conditions apparently overpowered him as he tried to make the Kincaid beach.

Lindsey has a photograph of that same beach 2 hours after low tide on May 27. There is no sign of a tidal river.

Why the difference?

After Eros's death, some blamed the extreme tidal range of June 23, but there was an even greater range between the tides on May 27. Why then the difference in the flow of water two hours after low tide -- or even earlier?

"You say the time of the (911) report was 4:37 p.m. . . ." Stryszak said via email. "The call was some minutes after Joe went missing. The person trying to call couldn't get reception from the beach and ran around on the beach trying to get it. The person eventually called another person, who called 911. I estimate that we began crossing that channel close to 4 p.m."

That would be only about an hour and a half after low tide, a time that should have been safe but wasn't. Stewart, Kelley and others who know the area well have an idea as to why things were different this day.

"It was definitely windy as we were walking back," Stryszak said. "I know this for sure, because Joe commented that the wind would keep the bugs away once we reached Kincaid."

A strong, southeast wind could, Stewart said, retard tidal flow into Turnagain Arm west of Fire Island, forcing more water up Cook Inlet to flood around the north end of the island into the gut off Kincaid.

"It is plausible," agreed Steve Gill, a Maryland-based scientist with NOAA who studies tides. "If there was a strong sustained wind, it could hold (the tide) up coming across the flats itself. It could locally affect the area."

Tides may be off in strong winds

Kelly said he'd avoid a trek to Fire Island on days with strong winds.

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"We see the strong winds as southeast winds coming out of Turnagain Arm," he said, "but these are channeled local winds. At the same time strong north winds will be screaming out of the Susitna River basin and straight down the main reach of Cook Inlet. And these north winds would be the ones that build the big seas that push south against the incoming tide and cause anomalies in the tidal flow. Such anomalies could result ... in unexpected surges in tidal flow.

"(My wife) and her father have done a lot of subsistence setnet fishing at Tyonek. They have to pay attention to the tides doing that, and she says that tides are often off when the wind is blowing hard."

Tyonek is an Alaska Native village on the north shore of Cook Inlet almost due west of Fire Island.

Near the island itself, Stewart said, "that water does stack up when the wind is blowing, and that rivulet close to the mainland never goes dry. It's down in a gully."

'A risky adventure'

Given the obstacles and dangers of getting to the island, he was surprised to discover how many people were trekking there when he worked on the submarine cable last summer.

"It's amazing to me people want to do it," he said. "It's a risky adventure. I had people arrive on the island last summer who said, 'We had to swim for it or we wouldn't have got here.'"

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On one occasion, he had to arrange for a flight off the island for a couple of tourists and their daughter who ended up stuck there. They'd left the mainland too late on the low tide and were trapped by the high tide.

"People have to realize there's a lot of risk in this," Smith said. More risk, possibly than many had realized.

"I'm wondering how the tides were so different from the month before," Eros's friend Lindsey emailed. "I could see a need to wade, but not the swimming.

"I mean, to some extent, I guess it doesn't much matter, right? That's what I keep telling myself. And yet, it does matter to me. It matters to me most, I think, because the tide charts show a nearly identical pattern to our trip a month earlier. And, while these things sometimes defy explanation, it seems natural to ask -- why now? Why were we safe and he wasn't? There's just some haunting desire to understand what happened."

Contact Craig Medred at craig(at)alaskadispatch.com

Craig Medred

Craig Medred is a former writer for the Anchorage Daily News, Alaska Dispatch and Alaska Dispatch News. He left the ADN in 2015.

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