Thousands of Seattle Homes to End Up Literally Underwater

If you followed the news this week, you probably read that the Antarctic ice sheet is has entered an irreversible melting phase, that will eventually lead to its collapse into the ocean and an over ten feet increase in the sea level.

Here’s an excerpt from the Seattle Times article about the melting Antarctic ice sheet:

“A large sector of the West Antarctic ice sheet has gone into a state of irreversible retreat — it has passed the state of no return,” said Eric Rignot, with NASA’s Jet Propulsion Laboratory in Pasadena, Calif.

That move by itself could increase sea levels by about 4 feet, Rignot said. But it also will help set in motion other changes that could cause the ice sheet’s contribution to sea-level rise to triple to 12 feet or more.

I was curious how a 12-foot increase in sea level might affect homes around Seattle, so I pulled up the handy Surging Seas simulator by Climate Central. Their simulator only goes up to 10 feet but even at that level you can see that the increasing sea levels will have a dramatic effect on Seattle.

Here are a few highlights:

  • 8,257 homes in King, Snohomish, and Pierce Counties will be literally underwater
  • Most of the Snohomish River Valley and the Duwamish River Valley will become ocean.
  • Lake Union and Lake Washington would both become saltwater bays.
  • I-5 through Fife would be submerged (along with 30% of the city of Fife)

Although thousands of homes would end up in the Puget Sound in this scenario, that only represents about one percent of all homes in the Seattle area. Still, the overall effects on our area would most likely be quite large.

Thankfully, we’ve got a while to figure out how to handle it (the article estimates 200-1,000 years), but unfortunately, if the scientists are correct, there’s absolutely nothing we can do to stop it.

Bottom line: Buy a waterfront home in the Seattle area for yourself and your kids to enjoy, but don’t count on passing it down to your great-great grandkids.

Apparently the visualization tool at Climate Central fails to properly account for the 20-22 foot differential between the Puget Sound and Lake Union / Lake Washington that is maintained by the Ballard Locks. Thanks to commenter Brad for pointing that out below!

0.00 avg. rating (0% score) - 0 votes

About The Tim

Tim Ellis is the founder of Seattle Bubble. His background in engineering and computer / internet technology, a fondness of data-based analysis of problems, and an addiction to spreadsheets all influence his perspective on the Seattle-area real estate market. Tim also hosts the weekly improv comedy sci-fi podcast Dispatches from the Multiverse.


  1. 1
    pfft says:

    As I’ve said before, real estate prices and buyers are going to have to incorporate climate into the equation.

    what is a house worth if it will be nearly underwater in 25 years?

  2. 2

    Actually Predicting Ocean Rising is Inexact per National Geographic

    It may be that bad in your childrens’ lifetime, maybe much worse.

    “…Most predictions say the warming of the planet will continue and likely will accelerate. Oceans will likely continue to rise as well, but predicting the amount is an inexact science. A recent study says we can expect the oceans to rise between 2.5 and 6.5 feet (0.8 and 2 meters) by 2100, enough to swamp many of the cities along the U.S. East Coast. More dire estimates, including a complete meltdown of the Greenland ice sheet, push sea level rise to 23 feet (7 meters), enough to submerge London and Los Angeles….”

  3. 3
    Brad says:

    The Ballard locks maintain a 22 foot differential between sea level and the levels of Lakes Union and Washington, so I don’t see how even 12 feet of sea level rise will cause them to become “saltwater bays”?

  4. 4
    The Tim says:

    RE: Brad @ 3 – Hmm, apparently the visualization tool at Climate Central fails to take that into account. Thanks for the heads up.

  5. 5

    RE: Brad @ 3 – Wouldn’t that depend on how close to the top of the locks the current high tide gets? Also, I would assume the current locks might need some redesign to deal with an extra 10′ of water. It’s even possible surrounding areas might need to be built up.

    The history of the lowering of Lake Washington is rather interesting, but factually and legally. A lot of the land was platted before the lake was lowered.

  6. 6
    mike says:

    At least it will get rid of those coal trains running through my neighborhood.

  7. 7
    Dave says:

    Having friends at the University who warned me years ago of the “imminent rise in water level” I checked my properties elevation before I bought it.

    Forewarned is forearmed.

  8. 8
    boater says:

    RE: Kary L. Krismer @ 5
    If anything the workload on the locks would go down. The greater the height differential the more potential energy the locks have to hold back. The lake is the high side so raising the sound side reduces the load on the locks.

    Glad I live 50′ above lake Washington.

    Given the damage that would do I’d be willing to bet they try to lock the whole Puget sound inlet. Not sure it could be done given the depth but it would become worth exploring.

  9. 9
    Blurtman says:

    This is great news! Less housing stock means higher surviving home prices. As Napa becomes a desert, Walla Walla becomes the New Napa. And folks with a lake view are now lakefront.

    Win! Win! Win!

  10. 10
    whatsmyname says:

    Two words, and one of them is “the”: The Netherlands. Some 20% of the land is below sea level, and they’ve been reclaiming land from the sea since the 16th century.

    I do like your simulation, though.

  11. 11

    By Blurtman @ 9:

    This is great news! Less housing stock means higher surviving home prices. As Napa becomes a desert, Walla Walla becomes the New Napa. And folks with a lake view are now lakefront.

    Win! Win! Win!

    Skyway is the new Kirkland.

  12. 12
    Eastsider says:

    Washington becomes the next California! Seattle -> San Francisco and Vancouver -> Los Angeles.

    I will be moving to Alaska ;)

  13. 13
    Scotsman says:

    This assumes the entire area isn’t first wiped out by earthquake or volcanic eruption. So many disasters, so little time.

  14. 14

    By boater @ 8:

    RE: Kary L. Krismer @ 5
    If anything the workload on the locks would go down. The greater the height differential the more potential energy the locks have to hold back. The lake is the high side so raising the sound side reduces the load on the locks.

    Could be. I haven’t been to the locks for years and was assuming that the current extreme high tide is close to or above what the current extreme low level is for the lake. That assumption was based in part on the data above suggesting that the lake would rise from a 10′ increase in sea level. Per Wikipedia the lake is about 16′ above the mean tide, but I wasn’t able to find data on the height from extreme high tides. (The record high tide was over 15′, but I don’t know if that’s 15 feet above the mean tide. I’ve not spent a lot of time around salt water.)

    One thing I did find though that I didn’t know is that Lake Washington prior to being lowered drained through the south end, into a now disappeared river called the Black River which drained into the Duwamish River. That raises at least some possibility that salt water could enter from that end again with a sufficient rise in sea level.

  15. 15

    FWIW, I played with the sea level simulator above and they show Lake Washington being affected at 9 feet, but not at all at 8 feet. So it’s possible they are dealing with extreme high tides overwhelming the locks. (Although if it’s only high tides the entire lake would not rise to that level in such a short time.)

  16. 16
    Lo Ball Jones says:

    You have to ask…at what point do the brainiacs at Goldman-Sachs start believing this stuff and making their bets accordingly.

    If true, that coastal properties will be under 3m of sea rise within 80 years, then those properties are essentially worthless. So, someone would have a bet somewhere. Alternatively, prices would certainly not be rising and perhaps falling as the gradual awareness of the inevitable takes hold.

    All kinds of long term infrastructure planning would change focus. You would not be building tunnels of any sort for example.

    Are these things happening? I am not seeing it.

  17. 17
    drshort says:

    By Lo Ball Jones @ 16:

    You have to ask…at what point do the brainiacs at Goldman-Sachs start believing this stuff and making their bets accordingly.

    They’re already placing bets on natural disasters via catastrophe bonds. Generally, the time horizon of one of these is too short for something as long term as sea level change, but it’s in the ballpark.

  18. 18
    Blurtman says:

    RE: Lo Ball Jones @ 16 – Say, didn’t those “Braniacs” have their errand boy arrange a bailout for GS? I seem to remember something like that…

  19. 19
    Erik says:

    I have heard so much crap about the ozone layer, the techtonic plates, the y2k bug, the Mayan Calendar and now the polar ice caps. This is not my problem and it will not affect me. I don’t think it really will happen. The “experts” have been wrong every other time. I don’t see them suddenly being right.

    Give me a discount on some waterfront property then. I will take it because I know this will never happen.

  20. 20

    RE: Lo Ball Jones @ 16 – Eighty years is a long time for real estate. An 80 year lease of real property would probably cost you pretty close to the FMV of that property.

    Also, the idea that climate change is irreversible is pretty much nonsense. One or two historic volcanic eruptions and we’ll probably all be thankful that we spewed so much carbon into the air so that temperatures only dropped 5 degrees. ;-)

    BTW, I recently learned from the folks over at the Puget Sound Seismic Network that Wired is a good source for geological news. The author of this piece is highly respected in the scientific community.

  21. 21
    SaffyThePook says:

    Seriously, Kary? The last time we were at 400ppm atmospheric CO2 was about 4 million years ago. I’d rather not wait that long for the ecosystem to reset.

    And Erik, the ozone hole was (is) real and its anthropogenic increase was stopped by banning CFCs. The Y2K bug was also real but was dealt with in time via a massive re-programming effort. The tectonic plates drive the very serious earthquakes we have in the region but if you choose not to keep emergency supplies on-hand because you “don’t believe in them”, that’s up to you. As for the Mayan calendar, you got me there. I traded everything I owned for gold coins and ammo in anticipation, but I’m sure they’ll come in handy some day.

  22. 22

    RE: SaffyThePook @ 21 – I didn’t say global warming wasn’t real, only that it wasn’t irreversible. I’m in the camp that believes it’s at least partially caused by the activities of man (as opposed to just being part of a natural cycle), but I still think things could happen that reverse it, such as a huge volcanic event or even a huge asteroid.

    Also, I don’t know how old you are, but the Y2K bug was greatly over-hyped. Yes a lot of programming was required to fix prior lazy programming, but despite all that the news media and software companies were still warning of dire results. Part of that is because that’s what the news media does (scares people) and part of that is because it helped sell software. So I can see why he would mention that. I would agree with you on the ozone hole and tectonic plates.

  23. 23
    SaffyThePook says:

    Kary, I didn’t say you didn’t say it wasn’t real ;o) I understand your take but what I’m saying is that it took 4 million years of volcanoes erupting and asteroids hitting to get the prior 400ppm level down to where it was at the beginning of industrial revolution. Could it happen more quickly with a humdinger of an event going forward? Sure, but we’ve got 4 million years of history showing that it’s pretty unlikely within our lifetimes or those of our kids. In fact, it didn’t happen previously over the history of our entire species. That said, if you lengthen the time scale 100X, the climate has changed quickly and radically at least five times. Unfortunately, each of those instances have also involved global mass extinction, so it’s a baby-with-the-bathwater kind of situation. I’d say we’re better off just trying to put the brakes on it now.

    As for Y2K, I’m old enough to have written some of that lazy code ;o). There’s no doubt that it was massively over-hyped by the media long after industry and government had ameliorated the issue. That said, if nothing had been done to fix it, it would’ve been a very serious problem.

    My point is that the media is the media and they’re going to do their fear-mongering thing no matter what the issue. It’s up to us to think critically and sift the crazy hype (Mayan calendar) from the justified hype (climate change).

    Anyway, to get this back on topic, I do think climate change will have repercussions for property values in our lifetimes, probably even within the next decade. It’s not that the sea level will rise enough to drown the current waterfront, it’s the increase in statistical variability of weather intensity. What used to be a 100 year storm will soon be a 20 year storm, if it’s not already. If you live on the shore, in a flood plain, near a slide zone, etc, expect stricter building codes, higher insurance premiums, and more frequent property damage.

  24. 24
    pfft says:

    Climate change is already here. My brother sent me a picture from California of a fire that was only about a mile from his house.

    Studies: Wildfires worse due to global warming

    The economic effects are real. my brother had to come home early and pack. His wife needed to be at work just in case. All of that costs time and money. They were packed up and almost had to evacuate. Which costs money of course. Imagine those poor people who lost their homes or that person who lost his life.

  25. 25
    Blurtman says:

    RE: Erik @ 19 – Erik, I drove by the Juanita Pub last night on my way to the nearby Cafe Juanita. It looked like a nice place, likely populated by locals medicating away their despair over living in condo hell.

  26. 26
    Justin says:

    RE: Lo Ball Jones @ 16 – Like the tunnel currently being dug beneath Seattle……

  27. 27
    wreckingbull says:

    I’m not so sure I agree with Brad. The 22-foot figure applies to a low tide. At high tide, you might be at about a 10-foot differential, and thus have saltwater intrusion.

    The reason this came to mind is that I have transited many times at high tide, and there is no way it is a 22 foot rise into the ship canal. I think your original post was correct. It might not be enough to make much of a difference, but technically, there would be times when saltwater would breach the locks into the ship canal.

  28. 28
    Erik says:

    RE: Blurtman @ 25
    Not a bad place at all. I lived up on 100th for those 2 years I owned that condo. I would walk to Juanita Pub occasionally and get blasted and walk home. It was generally a good time. Now I have 9 million unmarked bills and Norm’s only steps away from my doorstep. The barrel thief is a great place too. You can get a flight of whiskey, rum, vodka or whatever you want and the bartender tells you about the history of the booze and the differences. Great place. I like to go to Norms cause it is cheap and I like the people in there. I think I need either another remodel to keep me occupied.

    Also Blurtman, I learned that I can borrow a lot more money than I thought I could. I was told I could borrow 417k with no problem and more than that could get tricky. Maybe it’s because I got all that casheroo from my last remodel, so they let me borrow more? The point of me saying this is that if you find another good deal in your neck of the woods for me to remodel, let me know. I may be able to get the money to borrow it. I did miss that last one you showed me. If I could of pulled the trigger on that, I totally would have. I think I could have made atleast $150k on that one.

  29. 29
    Erik says:

    From the map, it appears north Everett will be cleansed naturally with salt water. Maybe that’s why Everett always say they are going to fix up the waterfront or fix up Broadway and never do? Maybe they know Everett will be underwater anyway, so they aren’t ever going to fix it up?

    The last big thing I remember that was going to happen to Everett was that the University of Washington was going to put a campus in Everett. Yet again, another lie. Again, could be because they know it will be underwater soon anyway.

    Does anyone know what is going on with the Kimberly-Clark mill? I vote they turn it into a drug rehabilitation center or a prison and get some of those meth heads that walk up and down Broadway off the streets.

    Just looked it up… they are turning it into a shipyard and provide a whopping 250 jobs.

  30. 30

    RE: Erik @ 28
    Norm’s is a great place. Very good happy hour prices, and dog friendly. What more could you want?

  31. 31
    Jason says:

    RE: Brad @ 3 – I work at the locks and we routinely have high tides of 12 and occasionally 14.5 feet. The top of the gates are only slightly higher than 22 feet above mean low water also called sea level. Once more than 6 feet of sea level rise occurs salt water will intrude into the ship canal. Of course if the Seattle fault has its overdue 7.0, the locks will drop one or two feet along with everything else north of the fault line and accelerate the process.

  32. 32
    Erik says:

    RE: Ira Sacharoff @ 30
    I am only moving because my rent is doubling. Love living next to norms. I wouldn’t say I am a huge pet lover, but I like the relaxed atmosphere the pets bring.

  33. 33
    Erik says:

    RE: Ira Sacharoff @ 30
    I am only moving because my rent is doubling. Love living next to norms. I wouldn’t say I am a huge pet lover, but I like the relaxed atmosphere the pets bring.

  34. 34
    wreckingbull says:

    RE: Jason @ 31 – Sounds like a cool job. I love telling visitors that the locks don’t need any power source to raise the water for boats coming entering the ship canal. They think about it, then have a light bulb go off in their head.

  35. 35
    justaguy says:

    When this story ran in the Times and on last week, the author of the study also include the projection that a 12 foot rise would flood PIke Place Market and much of downtown.

    Have to taken a look at the Elliott Bay views from the market and Steinbruck Park? The market sits easily 100″ above the waterfront, as does most of the downtown core and Belltown. Oops……

  36. 36
    Smith says:

    RE: Blurtman @ 9 – what have you been smoking? Walla Walla is a shit hole next to napa.

Leave a Reply

Use your email address to sign up with Gravatar for a custom avatar.
Your email address will not be published.

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>

Please read the rules before posting a comment.