Environment

Hundreds of people in Juneau’s Mendenhall Valley are living on the front line of a climate change disaster they didn’t see coming. This is Outburst, the story of how glacial outburst flooding has escalated faster than human imagination – and public policies to protect people.

KTOO takes you from the floodwaters to the glacier’s edge to uncover why the annual floods happen, how they got out of control and what can be done to keep Juneau safe.

On a drive through the suburban streets of Mendenhall Valley, “FOR SALE” signs have multiplied along the streets that flood year after year.

In the fourth and final episode of Outburst, KTOO’s Alix Soliman asks residents what they plan to do. Some feel they have no choice but to cut their losses and leave. Others hope to stay, pointing to investments they’ve made into their homes and the tight-knit Juneau community. 

Either way, many Mendenhall Valley residents feel constrained by another major problem facing Juneau: the housing crunch.

The U.S. House Natural Resources Committee is touring Alaska this week to take a closer look at the land they spend so much time talking about in Congress. 

Rep. Celeste Maloy, R-Utah, was in Juneau with 10 other members of Congress on Monday.

“We set natural resources policy, and obviously, Alaska is a big natural resources state, so we’re here seeing things on the ground so that when we’re talking about it in Washington, D.C., it’s not just an academic exercise for us,” she said.

They toured the Hecla Greens Creek Mine on Admiralty Island and flew over parts of the Tongass National Forest.

The visit comes after the Trump administration’s tax and spending bill, known as the One Big Beautiful Bill, was signed into law July 4. It boosted oil and gas leasing in Alaska, mandated the expansion of timber harvest on public lands, and allocated more than $7 billion dollars to grow the U.S. military’s mineral stockpile. 

Rep. Bruce Westerman, R-Arkansas, is chairman of the committee. At a press briefing at Ward Air in Juneau, he said there is a growing demand for metals like silver that are used in AI data centers and military weapons.  

“It’s imperative that Congress work with everyone who’s in the business to help figure out how to get more mining done here in the U.S., and not just mining, but also the refining of the metals, which is a huge issue,” he said.

Westerman says the committee could help Hecla further extend the lifetime of Greens Creek Mine, the most productive silver mine in the nation. Its mine life was recently extended by more than a decade. 

Alaska’s Rep. Nick Begich said forestry is another big focus for the committee.

“In the One, Big, Beautiful Bill Act, there are provisions to unlock additional forestry resources for timber, particularly in the Tongass, but across the nation as well,” he said. “This is something I hear from folks from Ketchikan all the way up to Yakutat on a regular basis. How do we bring timber back?”

The U.S. Forest Service is currently revising the Tongass Management Plan, which is set to take effect in 2028 and will determine how logging is done. 

The committee heads to the Kenai Peninsula tomorrow and will attend the Alaska Oil and Gas Association conference in Anchorage on Wednesday.

In Skagway, at the height of summer, hundreds of tourists wait in line – some patiently, some less so – to return to their cruise ships. But they can’t get there on foot. Instead, they wait for shuttles or small, orange boats.

Jeff Jarvie, of Riverside, California, experienced the rigmarole this week.

“It’s disappointing, because it’s a ship with so many people,” he said. “The water taxi takes a whole, like, process.”

But that process is in place for good reason. Skagway’s largest cruise ship dock, known as the Railroad Dock, has been off-limits to pedestrians since the summer of 2022. That’s when multiple rock slides tumbled toward the dock from a ridge to the east.

No one was injured. But the slides damaged infrastructure and resulted in dock closures that took a major toll on the local economy. An assessment by an engineering firm later concluded the entire slide area would eventually collapse, which it said would be “catastrophic in nature.”

That fueled widespread concern in the community.

“We know that we have this one spot that’s active,” said Reuben Cash, the environmental program coordinator for the Skagway Traditional Council, a local tribe. “Where else? Where else can we expect to see these geohazards show up?”

That question is the driving force behind an ongoing research project that aims to study rockslide risk along the rest of that ridge and elsewhere in Skagway. The initiative is part of a regional effort that aims to help seven tribal governments understand and respond to local geohazards.

In Skagway specifically, the issue is rooted in the fact that the area for thousands of years was under miles of ice. Those glaciers retreated long ago. When that happened, they exposed the now slide-prone ridgeline.

“There’s no longer that support,” said Cash. “These valley faces, these slope faces, are beginning to topple because they don’t have anything holding them up.”

A landscape of wiggly rocks and leaning columns

That toppling effect is what brought Josh Roering, a University of Oregon geologist, to Southeast earlier this summer. He’s been visiting the area for research since 2022.

While out on a day-long hike along the town’s most prominent ridgeline in June, he said the project has a few main components.

First, mapping when and where rockfalls have happened before, modeling where they could happen later, and simulating where rocks would end up if they did fall. That work included analyzing hundreds of rockfall events in Skagway between 2005 and 2022.

“We identify that there are parts of this valley that are much more susceptible to rockfall runout than others,” Roering said.

That means some slopes are both rockslide-prone and oriented in a way that could put people and infrastructure in harm’s way.

Another key component is gauging the ridge’s stability – and the extent to which rocks along it respond to everything from wind, frost and rain to trucks, trains and cruise ships. The researchers did that by placing 38 seismometers, which measure movement, in the area for about a month, two years ago. They’re now analyzing that data.

“The more wiggly these rocks are, the more sort of decoupled they are from the underlying mountain,” Roering said. “And so that is a relative measure of how potentially unstable they may be.”

Roering spent several days this summer going back to those sites and gathering more information. Along the way, he and another team member used photos and GPS data to pinpoint exactly where the sensors were placed. Then they mapped the geology around those sites and measured the angle of various rock faces.

During that hike in June, Roering stopped periodically to point out deep, vertical gashes in earth – some of which could fit a human. The ridgeline is covered in them.

Roering explained that the mountain – like others in Skagway – is largely made up of upstanding sheets of granite that are peeling apart, absent support from glaciers. That process speeds up when rocks, trees and other debris fall into the fractures, wedging them open. Then they start bending toward Skagway down below.

“Once you sort of got a big column of rock leaning this far over, it starts to become difficult for it not to flip over,” he said.

For Skagway, no “time bomb just waiting to happen”

The research has generated some good news so far. The ridge above town does not seem to be prone to a deep-seated landslide, like the one that killed two people in Haines in 2020.

“We know that we don’t have a time bomb just waiting to happen,” said Cash, of the Skagway Traditional Council.

That doesn’t mean there’s no risk at all. Right now, rockslide activity that could threaten life or property is concentrated in a handful of areas in the valley, including two main spots along the ridge that towers above the cruise ship dock.

But Roering said it’s clear the instability isn’t limited to those specific areas. It’s also present along the rest of the ridge and elsewhere in Skagway. As a result, he said, it’s likely the toppling effect will continue to ripple across the region far into the future.

A major remaining question is what actually triggers that instability and sparks rockslides. So far, Roering said, it’s not totally clear. But there seems to be more activity during spring, as temperatures warm.

“This was a surprising finding for us because it shows that the timing of thaw is way more important than rainfall for triggering these rockfalls,” Roering wrote in an email this week.

The ongoing research is set to wind down by 2027. It won’t remedy the gargantuan slide in the harbor that has already damaged infrastructure, threatened public safety, and inconvenienced visitors like Jarvie, the cruise ship passenger from California.

But the effort ideally will provide the community the information it needs to better understand the risks it faces – and to prepare accordingly.

“It’s not going to tell you exactly where rocks will fall,” said Cash. “But it tells us the higher risk areas where it’s more likely to happen.”

Correction: This story previously misspelled Luka Silva’s name in a photo caption.

Engineers from the City and Borough of Juneau are taking a close look at damage the temporary levee sustained during the record-breaking glacial outburst flood on the Mendenhall River last week. 

Some sections of the levee leaked, flooding a couple dozen homes. But it protected hundreds of others. 

Nick Druyvestein, an engineering associate at the city, has spent the week inspecting each HESCO block that makes up the levee built along 2.5 miles of the river. 

“I’m looking for tears in the fabric, any damage to the wire mesh, popped welds — really just looking to see if they’re they’re still standing up straight and if there is any damage,” he said. 

Some parts of the levee seeped, sank into the soil or lost sand through the bottom.

A tree punched a hole through one section near Dimond Park Field House, but the water didn’t rise high enough to flood through there. 

City staff are reaching out to homeowners to find out how they saw the levee perform during and immediately after the flood. Once they gather all of that information, they’ll create a damage assessment report. The report will help the city plan repairs and improvements to the levee before the next flood. 

“Our basis of design last year was to try and put everything four feet above what we saw the year before, but obviously, this year we saw higher levels in some areas,” Druyvestein said.

Water surged just inches from the levee’s top in some spots. 

Nate Rumsey, the city’s deputy director of engineering and public works, said he didn’t expect it to get that close since the peak flood height was less than 17 feet.

“There was water higher on the face of the barriers in certain sections than we anticipated based on the modeling that we did,” Rumsey said.  

So, city engineers say they’ll account for a potentially bigger flood as they prepare for the next major flood. They don’t have a timeline yet for when repairs will begin.  

In some years, Suicide Basin has released floodwaters more than once. But subsequent releases have historically been minor. Last year that happened in October.

A temporary levee in Juneau’s Mendenhall Valley mostly held back record-breaking floodwaters during the glacial outburst last Wednesday. But water lapped just inches from the top and there was some leakage, which led to flooding in some homes. 

Some Valley residents are worried the city’s temporary levee won’t hold up next year. City officials said they will stabilize the riverbank, repair the levee and build it higher for a flood that could break the record again. 

At a Juneau Assembly meeting Monday, Debbie Penrose Fischer, who leads a flood advocacy group, called it a near miss.

“What if it had still been high tide and the rain had continued?” she said. “If those conditions had prevailed, many believe this would have been another flood disaster.”

Last year, her home on Gee Street flooded and she was rescued on a raft. Her home didn’t flood this year, but she said she still doesn’t feel safe. 

The levee was controversial, and it is considered a stop-gap solution. The city doesn’t know how it would perform in floods larger than 18 feet. Experts still don’t know how big the flood could get, but it has grown over the past three years. It hit 15 feet in 2023, then 16 feet last year. Now, the record is 16.65 feet. 

Twenty-five homes along the river flooded because the barriers leaked. Part of the levee on Riverside Drive slumped towards the rushing river because the water eroded the land beneath it.

City Manager Katie Koester said the HESCO barriers that make up the city’s levee sustained about $1 million dollars worth of damage during the flood. She said she doesn’t know yet how the city will pay for repairs.

“It really demonstrated how temporary those HESCO barriers are in nature,” Koester said. “There’s a lot of vulnerabilities, there’s seepage, there’s undermining of the armament, right, that we have to care for.”

The city has not yet finalized the price of building the levee with materials donated by the U.S. Army Corps of Engineers. Koester said she expects it to be less than the $7.83 million budgeted for construction, but a pending lawsuit from homeowners could affect the final cost. 

Researchers and officials are still evaluating data from the flood, including how fast the water flowed and how high it reached on the barriers. The city will use that information to plan for future floods.

Alyson Cooper lives in the flood zone and testified at the meeting to thank the city for building the temporary levee.

“I feel for my neighbors that got water in their house, but there weren’t very many of them,” she said. “Mostly, there were hundreds of homes that were spared, and there were hundreds of people like me whose lives were not turned upside down this year, and I just want to thank you.”

A long-term solution for annual flooding is expected to take years, though residents are urging Alaska’s congressional delegation to speed up the process. 

Communities in Southeast Alaska are ramping up calls on the federal government to better manage the region’s booming sea otter population and its impacts on key fisheries.

The City and Borough of Wrangell approved a resolution in July urging federal agencies to work together with Alaska Native tribes and the state to address the proliferation of sea otters across Southeast.

Around the same time, the borough called on more than a dozen other governments and organizations to follow suit. So far, at least two communities have: Petersburg is considering a similar resolution, and Haines approved one last month.

The concern largely revolves around sea otters’ impact on species that are crucial for commercial and subsistence fishermen in Southeast Alaska. Critics say the otters’ eating habits are leading to the decline of species ranging from crab and oysters to sea cucumbers and abalone.

“In the 60s and 70s, you could drop a crab pot anywhere in Glacier Bay and catch all kinds of crab,” Haines Borough Assembly Member Craig Loomis, who supported the resolution, said in an interview earlier this week. “Now, it’s almost impossible to catch a crab.”

There is some scientific research that backs up the general concern. That includes a study from 2013, which found sea otters were escalating the decline of sea cucumbers.

But there’s still a long list of questions around the animals’ ultimate impact on the marine ecosystem and fisheries more specifically.

A paper published in 2024, for instance, concluded that while “the initial reintroduction of sea otters to Sitka Sound coincided with a notable decrease in abalone numbers,” the ongoing implications of otters on abalone are “much less clear and direct.”

What is certain is that the region’s sea otter population has increased dramatically since the 1960s, when the state reintroduced them. That happened after the species nearly disappeared amid the Russian fur trade.

The most recent population survey by the U.S. Fish and Wildlife Service estimated that there were around 22,000 otters in the region in 2022 – more than double the estimate back in 2008.

According to the survey, the population is still far below the number of otters the region should be able to support: 48,000.

Still, commercial and subsistence fishermen have reported major consequences from the repopulation for years. In Wrangell’s regionwide call to action, for instance, the city and borough manager wrote that the issue is at a “breaking point” in the community, and has led to the “near-collapse” of once-abundant crab fisheries and dive harvest areas.

Robert Venables, the executive director of Southeast Conference, said the population has also hit mariculture farmers.

“There was one that told me they felt like they were setting a cafeteria because they were being raided on a regular basis,” he said.

Notably, surveys and local observations indicate otters so far have not established a major presence in the Upper Lynn Canal, near Haines. But Loomis, the borough assembly member, says he’s concerned that will change.

“Now, are the sea otters coming this way? Absolutely,” Loomis said.

Similar efforts go back years

The resolutions coincide with a proposal last month from Alaska U.S. Rep. Nick Begich to roll back parts of the federal Marine Mammal Protection Act.

That law covers mammals, including sea otters. That means they are managed by the federal government and can only be hunted by coastal Alaska Native people for subsistence or traditional crafts.

The recent Southeast resolutions call on federal agencies to develop new management plans, provide disaster assistance to impacted fisheries and loosen restrictions that limit how Alaska Native hunters can use sea otters.

“The federal management mandate does not really allow an aggressive approach to managing that species,” Venables said. “So Wrangell’s taken the lead on that, and Southeast conference and others have spoken out in support. ”

It’s far from the first time the issue has come up. Communities, crabbers and dive fishermen have raised concerns about the issue and sought relief for more than a decade.

As recently as 2023, officials in Ketchikan pressed the Alaska Board of Game to devise a management plan for otter populations. The board dismissed the proposal given that the sea otters are protected under federal law.

And in 2019, federal and state officials gathered with scientists, fishermen and tribal groups to pinpoint potential solutions. That meeting resulted in a document that indicated next steps could entail more research, developing local harvest plans, and seeking funding to launch a sea otter skin sewing program.

When asked for comment, staff at the U.S. Fish and Wildlife Service passed along several resources related to sea otter management in Southeast but did not respond to questions about the resolutions or the issue more broadly. Staff at the Alaska Department of Fish and Game declined to comment and directed KHNS to the federal agency.