The Vanport Flood: This Weekend In Weather History

63 years ago this weekend, Oregon’s 2nd largest city was erased from the map in hours.  If you’ve never heard of the Vanport Flood, read on…it only happened 5 miles from downtown Portland.

I love weather AND history, so I find this flood fascinating, especially since it’s results echo through Portland even in 2011.

I’ll be brief, since it’s a long story.

During World War II (1940-45), huge numbers of workers were brought in to work in the shipyards here in Portland.  There was an urgent need for housing, so a city was quickly built and called VANPORT (Vancouver+Portland) on the flats north of Portland.  That’s the low area west of I-5 around Delta Park where PIR, Heron Lakes, and Delta Park West is now.  That city contained 40,000 at it’s peak, making it the 2nd largest city in the state! 

After the war, lots of folks moved away, but there were still 13,000+ residents there by the Spring of 1948, three years after the war ended.  Even a college had opened in the city for the returning GI’s…the Vanport College. 

The winter of 1947-48 brought massive snowfall to the mountains of the Pacific Northwest and Rockies, along with lots of rain.  At this time there were very few dams to hold back spring floods on the Columbia and Snake Rivers…although Grand Coulee and Bonneville Dam both were operational.  The Columbia River rose throughout May 1948 and by Memorial Day Weekend was approaching the 30′ level on the Vancouver gauge.  That’s within 4′ of the all-time high in 1894.  For comparison, that 1948 level is about 14′ higher than the river is right now!  I notice the Portland Housing Authority had put out a notice in the week before saying  “REMEMBER: DIKES ARE SAFE AT PRESENT.

That didn’t happen.  On Memorial Day, May 30th, (used to be on that date instead of the last Monday of May) the railroad dike on the west side of the city (where the railroad is now) burst around 4:20pm.  A 10 foot wall of water went surging into the city.  By sunset the city was inundated and remained so for over a month.  A few factors helped keep the death toll quite low (just 15):  it was the holiday weekend with lots of people out of town and mild temps plus bright daylight kept confusion to a minimum too I suppose.  Here’s the view two weeks later from just about the same vantage point.  Note the triangular are of trees on the edge of the slough in both pictures: 

Interesting to note that the river kept rising, and peaked about the date this picture was taken…at exactly 31′ on the Vancouver gauge.  The flood was the 2nd highest on the Columbia River since record keeping began in the 1800s. 

Here are the results:

1. About 1/2 of the residents were of African-American descent; largely settling into north and northeast Portland following the flood.  Lots of  good information about this online which is way out of the scope of a weather blog, but really interesting.

2. Vanport College was called “the college that wouldn’t die”, restarted in downtown Portland, and became Portland State University.

3. The town wasn’t rebuilt, but became a raceway, a park, golf course, and wetlands. 

4. The Flood Control Act of 1950 spurred more dam building along the Columbia and it’s tributaries, due to the 1948 flood.

Chief Meteorologist Mark Nelsen

297 Responses to The Vanport Flood: This Weekend In Weather History

  1. thejory (Sandy) says:

    Went for a hike part of the way up on Larch Mountain (Oregon) today. Beautiful blue skies most of the time.
    I had not been there for a couple years. I was shocked how many clearcut areas there were. Very Ugly! 😦
    Plus the heavy logging trucks did quite a number on the road. 😦

    What I don’t understand, that this road gets quite a bit of traffic from tourists that are following sightseeing maps from the Columbia River Gorge.
    But the county / state actually allowed all that mess.
    It looks like a bomb went off in places up there. It looks terrible. Where before you could into the forest, you just see mountainside and more forest. But now you just see a strip of trees near to the road, and a nasty clearcut.

    I understand people need to make a living, and these companies may own those parcels. But they didn’t need to do huge clearcuts. They could have done selective logging. AND, are they going to repair the road, or are they going to stick the county with that one? (which of course, probably means it won’t happen, which reflex badly on both the county and the state from the point of view of all those tourists)

    OK… Off the soapbox. Apologies if I offended anyone, and for the off-topic post.

  2. Rob "Wrath" S.E. Portland says:

    3 PM update

    *Upper Air Analysis
    850Mb: +2c to +3c
    500Mb: -24c to -25c

    SBCAPE: 500-1000J/kg, 1500J/kg Cascades
    MLCAPE: 100J/kg
    MUCAPE: 500-1000J/kg
    BULK SHEAR: 20kts
    PWAT VALUES: .62″

    As my analysis earlier indicated stronger than forecast instability has developed. We cannot rule out a shower or t-storm now especially now that the flow aloft has turned southerly and perhaps slightly south-southeasterly at that.

  3. Cgavic sandy Oregon 1,100 ft says:

    My parents got married in April of 48, and lived in an upstairs apartment on Denver ave in north Portland.

    Vanport was at the north end of Denver ave.
    As soon as mom and dad got back, that’s when they heard all the noise from the flood, people yelling, sirens going off due to fires breaking out in the north area. Smoke was in the air.

    I just got off the phone with mom. She just remembers snow, then rain, then heat…a domino affect.

    Question….why haven’t the networks picked up on this??

  4. Cgavic sandy Oregon 1,100 ft says:

    That’s how Portland got part of its history. Amazing.

    My mom, (who just turned 86), well remembers the vanport flood.

    My parents got married April 3, 1948.

    We found a picture of them with their first house in oak grove Oregon. In snow.

    My mom said her and dad delayed their
    honeymoon due to the torrential rains.

    They stayed in their apartment in N E Portland at the time.

    Early memorial day morning, 1948, mom and dad, and dad’s parents, went to the beach on the Oregon coast.

    Of course then they were hearing reports of a flood in vanport (mom said it was hot that weekend) they jumped in the car and rushed
    back to NE Portland

    That night (hot) and following days they could hearing all kinds of noise, water, people yelling, sirens going off.

    Correction..their first house, in oak grove, was purchased in December of ’48. In snow.

  5. bgb41 says:

    12Z GFS for Fairbanks, Alaska

    Can we trade?

  6. pappoose in scappoose says:

    Dual Polarization Technology = Clutter Cleaner. Hahaah!

  7. It would have to hit a somewhat hellish 270 degrees tomorrow in order to bring my average high up to normal.

  8. Rob "Wrath" S.E. Portland says:

    12z SLE Sounding: Convective Temp 55. Max Temp: 56. 58 here and rising… The other parameters aren’t favorable, but that was before we got these sunbreaks and obviously warmer temps than forecast. Therefore more instability, better LI, steeper lapse rates may be the end result. Hmmmm.

  9. jbpdx says:

    Here’s the damage. For March, April, May 2011:

    83/92 days BELOW AVERAGE that’s 90%.

  10. It’s warmer now than at any point yesterday! 53.4

  11. Rob "Wrath" S.E. Portland says:

    A few sun breaks poking through the clouds here. Depending on how many we see this afternoon and if we can get towards 65F I would not rule out a shower or maybe t-storm especially south or southeast of Portland.

  12. Raining here…at least it’s a warm rain…50 degrees right now.

  13. W7ENK says:

    Wow, really?!? >_<

    Ala. town hit by tornadoes bans FEMA trailers

    I’ll just leave my political opinion out of this…

  14. bgb41 says:

    5/29/2011 Oregon (All) Temperature Summary

    High:74 at Echo( 680 ft)
    Low: 52 at Blalock(280 ft) & John Day River B(305 ft) & Rufus(185 ft)

    High:29 at CRATER LAKE RIM(7050 ft)
    Low: 21 at CRATER LAKE RIM (7050 ft )

    Largest Diurnal Change: 32 degrees
    BEND WATERSHED (55/23 ) (5330 ft )

    Heaviest Rainfall:
    0.93″ at SILVER BUTTE(3973ft)

  15. Kyle From Silverton says:

    Jeeze Jesse you don’t need to be so blind. All our artic air has happened either early or late in the winter and the November event was more impressive at your house.

    WEe had a cold november but that’s all it was. Not a cold January or even December and if it weren’t for the last week Feb being artic air I bet the numbers would’ve been higher then average….at least at night.

  16. Karl Bonner says:

    At least two channels (6 and 8) are forecasting lows of 41-42 for The Dalles but mid to upper 40s in Hood River and Cascade Locks, which makes no sense this time of year – especially with a west wind. I know the weather feels kind of like mid to late October, but the stations should know better than to expect an October-like distribution of relative temperatures.

  17. bgb41 says:

    Record late season snowfall of 5.3″ at Ely, Nevada this afternoon.

  18. bgb41 says:

    00Z GFS – Warmest run of 2011. Eleven days in a row above 70 degrees. Something tells me this is a bit optimistic.

  19. Ashley Watson says:

    don’t worry everyone we will probably return to above normal temperatures just in time for next winter. That very distinct possibilty just chaps my hide!!!

    • Jesse-Orchards says:

      Every inaccurate, alarmist post you’ve ever made (all of them) chaps mine!

    • Kyle From Silverton says:

      Spot on! It just chaps my hides. I like that phrase! 🙂 Made me nearly laugh out of my chair.

      If it weren’t for that stupid inversion we would’ve had several 60+ readings for Portland during January.

      So true so true my friend.

      We now return you to our daily scheduled program.

  20. The LOW at Fairbanks was 61 today. The HIGH today at Portland was 56.

    • W7ENK says:

      Sad. 😦

    • boydo3 500, N Albany says:

      Fairbanks. The new summer vacation hot spot!

    • boydo3 500' N Albany says:


    • boydo3 500' N Albany says:

      OK, back on the block. wifi funkie wunkie
      Fairbanks, the new “vacation hot spot”. And reduced rates during the off-season. “sure, I’ll have another IPA” whoops. Loud in hear. Gotta go..
      No sun no fun unless you’re with your hun.
      Then it don’t matter if the sun don’t shine
      cuz you’ll find a smile when you drop them blinds.

  21. Josh (Gresham) says:

    Thunderstorms much?

    • W7ENK says:

      Meh… if I can’t see the lightning or hear the thunder from my location, then they mean nothing to me. :yawn:

  22. Longview - 400 ft says:

    Still have a fire going in the wood stove two our from June. This reminds me of May/June 2008.

    • Longview - 400 ft says:

      Still have a fire in the wood stove two days out from June.
      This reminds me of May/June 2008. I kept wood in the box until the middle of June when I was not sure what the weather was going to go Summer temps or early Spring temps.

    • W7ENK says:

      That’s okay. Last year was much the same, too. I had to use the furnace on the 4th of July.

  23. W7ENK says:

    What a fine Mayvember day it was today, wasn’t it? Mid 50s across the board, just a few light sprinkles that happened only everywhere I went this afternoon and seemingly nowhere else, it’s days like today that make me look forward to the dog days of Juneuary!

    It’s just around the corner… :eyeroll:

    • Jesse-Orchards says:

      But didn’t you see the long range 18Z GFS?? Why it’s the talk of Battle Ground!

    • W7ENK says:

      Yep, I saw it: Epic cold and snow, just wait two weeks!

      Anyone wanna bet 2011 doesn’t see one single day over 90 degrees? First time since 1954!

    • W7ENK says:

      *Here at PDX officially, that is.

    • W7ENK says:

      Winter is clearly setting in early this year… or is the last one not over yet? I can’t tell anymore.

      And wouldn’t it just figure… I no sooner get home and go to take the dog for a walk, it starts pouring! FML

    • bgb41 says:

      Just trying to think positive Jesse. I am fully aware that the NWS is not believing that solution.

    • Mike near Clackamas Town Center says:

      An early look at the 00Z looks pretty decent…We only have to endure 4 more cool and wet days. Next weekend looks better for outdoor activities 🙂

  24. bgb41 says:


    HIGH 54.3 LOW 38.4

    *Today was the coldest day of the Month
    *Last time it was this cold was April 27th when I reached 53.

  25. bgb41 says:

    18Z GFS = Warmest run of 2011.

    9/10 ten days are in the 70’s and 80’s at the end of this run 🙂

    Will be crossing my fingers on the 00z to follow suit.
    This heat and sun is still in la la land and most of us know that nothing is set in stone this year till we get up to the events.

  26. Josh (Gresham) says:

    Can’t believe there was a couple of feet of water from flash flooding right next to the first house I lived in in Wheaton.. Crazy

  27. bgb41 says:

    Death Valley map as of 1pm. Stovepipe Wells is 70. Average high for this date is 104 degrees there. Big Pine Creek in Kings Canyon National Park at 11,000ft is currently 9 degrees above zero. See photo.

  28. bgb41 says:

    Las Vegas, Nevada. Average high for the day is 93. Noontime conditions are listed on link here. 63 degrees overcast with winds gusting NW at 35mph at North Las Vegas airport with blowing dust. Think of all the people who were gonna get a suntan lol.

  29. Josh (Gresham) says:

    So hearing reports out of my hometown (Wheaton, IL) of 1 inch of rain in 15 minutes, another person I know said the windows on her house shook it was raining so hard, and the major flood report was literally on the corner where I lived for 4 years. Crazy stuff

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