Loop Group Goes Underground

Update: 10/16/06

Randy Gragg weighs in on this issue in his Sunday O column.

Original Post: 10/9/06

According to the Portland Tribune, the next phase of the downtown Portland freeway loop study (known affectionately as the “loop group”) will include consideration of a tunnel to replace the Eastbank Freeway.

32 responses to “Loop Group Goes Underground”

  1. Oh fuck no.

    I lived through about 15 years of the Big Dig in Boston. Its still going on. I sure as hell didn’t come all this way to put up with another fiasco.

    Yes, I’m sure its very different than Boston, but I want no part of it.

  2. The first thing that comes to mind every time talk of covering I-5 comes up is the Big Dig on the East Coast. How expensive it was. How the roof over the highway leaked and eventually fell apart falling on the roadway. How it was riddled with controversy and contractor corruption. How it basically has not yet done what it was supposed to do.

    Safety also comes to mind. First of all, covering I-5 on the Eastbank would place the freeway below the level of the Willamette River. During the big flood in the 90’s, part of the interchange to the Banfield was under water. The flood waters also lapped at the doorsteps and found their way to the basements of many lower Eastside businesses. Lowering the level of the I-5 would create a greater risk of the freeway becoming flooded.

    Covering I-5 would also require hazardous materials be rerouted onto surface streets. The question also arises what would happen if there was an accident that causes vehicles to catch fire? Or just a bad accident where combustibles and/or fumes leaked from trucks or other vehicles? Or even just a bad accident that trapped people in the tunnel?

    Then there is the big question, the cost and who would pay for it? I doubt park users would pay for a share because access to the riverfront is currently free. Likewise, I doubt bicyclist would be willing to directly contribute because they don’t want to pay for anything including bicycle infrastructure. It is even highly unlikely any private enterprise that might use the land a top the freeway would even be willing to pay for construction. I also doubt all those including advisory committee members, or those in the Westside high rises that look down on the freeway, or just about anybody else calling out to put I-5 underground would be willing to shell any really, really big dollars for the costs of the project. Furthermore, any increased taxes on freight carriers or transportation businesses like those located on Swan Island and use I-5 would probably be met with full-blown skepticism. As for motorists, they are already financially overburdened, not only to pay for roads, but also because motorists subsidize bicycle infrastructure, sidewalks, nature trails etc.

    When there is a greater need to add road infrastructure and capacity, it makes no sense at all to talk of aesthetically redesigning a freeway already in place. Functionality, the Portland transportation system is fast becoming a crisis situation. The cracks are showing and failing in part because there are too many subsidies to alternative modes and too few people being charged (just motorists) the true costs of providing transportation system needs. Furthermore, there is too much attention being paid and too much money spent for developing alternative modes and aesthetics rather than meeting the functional needs of taxpaying motor vehicle users.

    If the people of Portland are intent on burying something, bury Max through downtown Portland, and pay for it with a surcharge on transit fares. Instead of slow creepy crawly snake like travel on the transit mall, make Max a reasonably expedient system for cross town commuters, not just a “to and from” downtown system as currently being designed and developed. From a functionality standpoint, it would make far better sense to bury Max underground than cover freeways.

  3. I laugh whenever this comes up, which seems to be about every 5-10 years. Occasionally, they throw ripping out the Marquam Bridge in there, too.

    C’mon, folks, it’s the largest north-south route on the West Coast, until you head much further East. We have the Katz Eastbank Esplanade right next door, C-TRAN express buses use that specific stretch of freeway, and north-south local public transit is close by, via. 6-MLK and 70-12th Ave.

  4. To the “who pays for it”, part of the theory is that as property values go up, the value of the land re-claimed, plus the amount that will be required for major maintenance in few years anyway, will be sufficient to fund most of the project.

    This is a hypothesis that still has a lot of variables in it of course.

  5. The east bank section of the I-5 corridor including the Marquam needs to be replaced but making it a tunnel is a joke.

    Anything, any construction activities that is part of the same ROW will disrupt the city and all stakeholders in a big way.

    This disruption factor would be part of the hidden costs that would be over an above actural costs.

    To me the only reasonable solution to rebuilding the east bank I-5 corridor is replace it by moving it to a raised structure like the Alaskan Way in Seattle and it should be located over the heavy rail tracks a couple of blocks to the east.

    A new raised east bank I-5 Freeway will match up better with a new I-84 interchange and connect back to I-5 going north at a simular elevation.

    The Marquam Bridge has to go because it has more problems them all of the other bridges in Portland with the biggest being failing critically when it comes to safety.

    The estimated cost to rebuild and replace this failing section of the I-5 east bank of the freeway from the Marquam Bridge to the Freemont Bridge with 4-lanes in each direction has been estimated to be approximately $8 to $10 Billion Dollars.

    It has been estimated that the whole I-205 corridor could be widened to 4-lanes for full circumfrance for $2 to $4 Billion Dollars.

    Widening I-205 also eliminates the Terwilliger curves from playing the role it does with through truck traffic that should be re-routed away from core Portland.

    A 4-lanes I-205 has the potential to redirect 30% of the current traffic out of the I-5 corridor.

    We must reduce congestion, emissions and improve safety in the I-5 corridor or continue to kill the people and businesses that are the stakeholders

    A 4-lane I-205 has to be part of any solution to the I-5 corridor because it is the only project that we can afford that will bring real benefits.

  6. Well let’s face it: I-5 between the marquam and fremont bridges is a joke. I believe its the busiest freeway in the region and when you consider that its only like four lanes thru most of that stretch, it makes sense that we have a discussion about how to improve traffic flow especially at the terminus of I-84.

    If were gonna spend the billions to improve and enlarge this freeway, we should definitley look at moving it.

    Moving I-5 is nothing close to the big dig. Instead we’d be building a 2 mile tunnel with a couple of on/off ramp access poings and rerouting the interchange with 84.

    I’m surprised Terry and JK aren’t on board with this because its the only legit way to increase the capacity of this flawed freeway.

    although I think most people here would agree with terry that max needs a tunnel as well…we should be mindful that freeways are a vital part of our region and this section of I-5 in particular is in dire need of higher capacity.

    In the end, we can add capacity for commuters and freight, improve the safety of motorists, reclaim our iverfront (which is invaluable) and create prime buildable land in the center of the city which is potentially worth billions. Its a no brainer in my opinion.

  7. “This is a hypothesis that still has a lot of variables in it of course”


    It’s complete bullshit.

    And amazingly similar to the Urban Renewal rehtoric.

    Rehtoric which leaves out the 4 or more decades needed to retire the mounting UR debt in Portland.

    With TIF revenues far short of projections, many projects far over budget, tax abatements handed out inside UR districts, outcomes no where near the promises made and not a single elected leader willing to raise a single red flag there won’t be any extra revenue for a Portland Big Dig.

    Hell, there won’t be enough revenue for basic services.

  8. It has been estimated that the whole I-205 corridor could be widened to 4-lanes for full circumfrance for $2 to $4 Billion Dollars.
    As a comparison, I would love to see how much additional transit service we could get for that kind of money.

  9. Nathan wrote [i]Well let’s face it: I-5 between the marquam and fremont bridges is a joke. I believe its the busiest freeway in the region and when you consider that its only like four lanes thru most of that stretch, it makes sense that we have a discussion about how to improve traffic flow especially at the terminus of I-84.[/i]

    Actually that is patently [b]false[/b]. If you take a look at ODOT’s 2005 Transportation Volume Tables, you will find a significant drop in vehicle counts on I-5 between the Marquam Bridge (139,800) to the Morrison bridge (96,200), to the Burnside Bridge (75,400), to the underpass for the southbound I-5 to eastbound I-84 transition (91,200), to Holladay Street, just north of the I-84 ramps (135,000).

    In the middle of this stretch, traffic on I-5 actually drops by nearly 50% compared to either north or south of the I-84 ramps. Even personal observation backs this up; the traffic jam usually starts at the I-84 to I-5 ramps in either direction; but in the middle is often OK.

    For the record, the busiest stretch of freeway isn’t even on I-84. It’s on I-205 north of Division (179,600); however closely followed by I-84 west of 33rd Avenue (170,300). The busiest stretch of I-5 barely exceeds 150,000, and that is between Tualatin and Highway 217 (where 1 out of every 3 vehicles is bound to/from Highway 217 or Kruse Way.)

    The rationale for moving the highway isn’t for safety, it’s to make room for developers and parks. Let them pay for the freeway, and the land to relocate the freeway to, if they want it so bad. The last thing we need is to tie up our decreasing transportation dollars on a project that clearly has no transportation need – and tunnelling presents a huge slew of problems (i.e. earthquake resistance, emergency evacuation, hazmat freight routing) – problems that we currently don’t have to worry about as much.

  10. Erik,

    I don’t understand how you can essentially say that I5 is fine as is.

    Clearly, I5 is not the busiest freeway, but let’s realize that the section between the marquam and fremont is basically standstill during drive time.

    Maybe the many access points limit traffic flow?

    I’m not sure, but there’s no doubt that this section of freeway needs *major* improvements.

    Moving the freeway does not just benefit a few developers, btw. I think the city and everyone in it benefits!

    The freeway must be moved- but hopefully we *can* recover some of the cost from that project by selling land. Certainly, the land is worth a good chunk.

  11. To address Nathan’s questions:

    What exactly are the reasons why this stretch of freeway (I-5 between mileposts 300.0 and 302.0) need to be drastically altered; given that this stretch was completely rebuilt some 10-15 years ago; that it doesn’t exactly have a major safety flaw; that it isn’t any more congested than other stretches of freeway in Portland…?

    I’m not sure what you mean by that it’s standstill – so are the wider, straighter stretches of road in any direction from it. My experience is that the stretch in question is actually better than the other stretches; and partially because access to the road is limited (particularly northbound).

    If we are going to spend hundreds of millions of dollars, I want to know why, what are the alternatives (including the “do nothing” alternative), and what is the exact benefit? So far, the biggest benefit is “to free up the waterfront”, which has nothing to do with transportation needs. Meanwhile, we would tear up the Central Eastside Industrial District for at least three to five years to relocate the freeway, disrupt businesses and most of the west-east travel routes through Portland along with the MLK/Grand couplet, and further move light industrial and commercial business away from the city’s core, to build more unneeded, unnecessary high cost urban residential areas.

  12. Erik,

    I think we’re looking at this issue from different perspectives ;)

    First off, you see urban residential development in the central city as “uneeded and uneccessary”

    I couldn’t disagree more. More than a million people will be moving to portland over the next two decades and they all have to live somewhere! We should be increasing the density of the central city in order to grow. Succesful and lively cities are dense in the center!

    The most valuable thing we have in this city is land! In fact, the eastbank land is invaluable when you consider how it could tie the East and Westsides together.

    Moving the freeway doesn’t mean getting rid of the light industrial emplyment center. Rather, we should exploit that zone and encourage technological and creative industries to call it home. Its all about the zoning!

    By moving the freeway
    We can add tens of thousands of residents along the eastbank and MLK and add thousands of jobs as we densify and infill the CEID. Also, we’ll have landmark parks and a seamless transition from eastside to westside. Then there’s the improvement in traffic and freight transportation through the center city.

    Of course this is a radical vision, but portland is famous for radical visions and we *need* plan for the intense growth that is coming.

    We should be cautious with changes of this magnitude…but the need is there.

  13. Its all about the zoning!

    No, its not. Its all about economics and money. The first time someone comes along who wants to build a multi-story condominium on vacant land in the “industrial zone” the city council will change the zoning.

    Take a look at that New Season’s store parking lot next to the Max stop on Interstate. It violates all sorts of rules about how development is supposed to occur near transit stations.

    Portland is no different than Woodburn. It is not going to stand up to the political pressure for immediate economic benefits from new development because of some theoretical urban design standards.

    The idea that you are going to fix poor transportation decisions by zoning is as false as the idea that you can engineer a road for 55 mph and limit the speed to 25 by putting up signs and writing tickets.

  14. Ross,

    I see your point. However, correct me if I’m wrong, but I believe Chris has presented info to the effect that Van has been using zoning to its advantage for years.

    Why can’t PDX use the zoning to our advantage as well? By designating special zoning we are not attempting to fix poor transportation decisions, we are rather attempting to conduct growth within the limits of a master plan. What am I missing? Why can’t zoning be used to protect the CEID?

    One way I can see to really make this happen is to grant exceptions from any type of height limits on new buildings in residential zones, especially in the eastbank area. Of course let’s protect our view of Hood from certain places but shit, u can’t even see it from waterfront park really due to the monstrosity of a freeway now anyways!

    If the city decides: hey u can build a super tall condo tower on Grans, but says everything on 6th and 7th must be light industrial or creative office space or studios…then what’s the problem? The value of the residentially zoned land on Grand becomes valuable while the relative value of the CEID land becomes less valuable…

    I don’t see what the problem is and how this relates to “poor transportation decisions”

  15. OK, I don’t see why we need to move I-5 to accomplish any of the goals – infill residential development, light industrial redevelopment, etc.

    We don’t need to move I-5 to “tie the westside and eastside” together – I-5 is not some sort of impermeable wall like the Berlin Wall. In fact much of I-5 (particularly on its southern end) is built on an overpass with plenty of underpasses; and with the Eastside Esplanade, a lot of pedestrian/bicycle friendly underpasses.

    The only reason that is given to move I-5 is to open up the riverfront to revelopment (and some greenspace, but that’s secondary to redevelopment – and there’s already public access to the river on the eastside this very second) – and everyone knows that since riverfront housing is more desirable it will be worth more money.

    Never mind the fact that there’s no reason to move the freeway (which was rebuilt about 10-15 years ago) or remove the Marquam Bridge (which has had its share of renovations and retrofits) – both of which have already cost us tens of millions of dollars; and that the freeway is generally OK. Never mind the fact that the housing shortage in the Portland area is for AFFORDABLE housing – there are plenty of $250,000 and higher condos and $350k+ homes in the Portland area. Just look in the Sunday Oregonian’s real estate listings. All of these rich people need “us poor slobs” to serve them food and wash their clothes and handle their meanial customer service requests – where do we live? In Timber, Government Camp, Hood River (oops, the last two are taken by the rich people too), Stayton, and Grande Ronde? So much for “smart, transit-oriented development” when the people who need transit the most are now the most disadvantaged by it.

    We can redevelop the eastside TODAY, with no relocation of I-5 whatsoever. If developers want to relocate I-5, then the developers can pay the hundreds of millions to buy the land further east at market price without the benefit of condemnation; build the freeway (with no construction delays to current I-5 traffic), and then buy the land underneath I-5. Otherwise, that “investment” to relocate I-5 is taking dollars away from real, current problems – like congestion, health care, education, State Police, etc. – after all, I-5 is a state highway, and therefore would require (at least some) state dollars to relocate as well.

    It’s a solution that is missing it’s problem and is an avoidable cost. Quite frankly, I don’t want to pay for it, and when I’m locked out of the housing market because of speculation and greed – I have no desire to subsidize any developer or any wealthy multiple-home owner, even if you call it “transit”. After all, the “affordable housing” project in the South Waterfront is on hold, because its builder decided that the “finances don’t pencil out”.

  16. “What am I missing? Why can’t zoning be used to protect the CEID?”

    Because if there is no longer a market for industrial uses in expensive real estate, no company is going to conduct industrial activities in that area due to economic forces.

    Please tell me why exactly we should have manufacturing and heavy industry in the central city in the first place?

    One model for for cities is to have a dense, cultural/residential inner core, with all the polluting activities such as industry on the outskirts, where the land is cheaper and there is less congestion when linking industry to distant interstate/international markets.

  17. What am I missing? Why can’t zoning be used to protect the CEID?

    It can, against political weak owners. But once a piece of property is bought by a politically well-connected developer who wants to develop the land for some other purpose, the city council will cave. That is the pattern that we saw with New Season’s on Interstate.

    Please tell me why exactly we should have manufacturing and heavy industry in the central city in the first place?

    This is precisely the argument you will hear from those who want to develop the CEID.

    The CEID is a major employment center with literally 10’s of thousands of jobs. There are reasons those employers chose to locate there. There is a combination of infrastructure that makes it a very desireable location for all kinds of light industrial applications. If the city suddenly invests in new infrastructure, designed to make it more desireable for residential, commercial and entertainment then those uses will eventually force out the light industrial users and Portland will lose the jobs. Those jobs may or may not move elsewhere.

    Right now the area is starting to attract various creative companies that need light industrial facilities. As you point out, most cities don’t have that in their core any more. Portland does, and that is an advantage for the city as a whole.

    Its one thing to remove the freeway and open up the waterfront. Its quite another to have to justify a billion dollar investment in a tunnel with high density, high profit new development that displaces the existing industrial employment.

    If developers want to relocate I-5, then the developers can pay the hundreds of millions to buy the land further east at market price without the benefit of condemnation;

    That is ridiculous. There is simply no way for developers to buy land on the scale you are talking about at “market price without the benefit of condemnation”. All condemnation does is require someone to sell at market price rather than holding a public project hostage to an inflated demand.

  18. Zoning is working so far. The EXd zoning along MLK/Grand, and the neighborhoods refusal to consider expanding it, was the major determinant of where the proposed Streetcar alignment was drawn.

    I believe that having a location in the central city for “non-office” jobs is a critical advantage for Portland and I hope we have the courage to hold the zoning line. But as others have said, that’s going to get more difficult as land values create pressure to redevelop to other uses.

  19. The character of Central Eastside is changing as we speak with software and design firms replacing box manufacturers, etc. Its only a matter of time.
    Any city worth its salt will try to do something better than a freeway along its waterfront. Duluth, Minn. put its Interstate in a tunnel, surely Portland can.
    Myself, I would remove the freeway and the Marquam Bridge (what an eyesore) and not replace it…maybe adding a lane to I-405 (and changing its name to I-5) and to I-205. By adding arterial roadway capacity to the new Caruthers lightrail bridge across the Willamette, the Central Eastside would actually have better access to the freeway network.
    Thru traffic would have to manage on MLK/Grand, or use MAX, or move to a condo in South Waterfront. I want an East Portland beach on the Willamette and the rest of this valuable lane back on the tax rolls.

  20. Actually, it was my argument that HEAVY industry has no place in the CEID – I don’t think anyone would want to see an iron smeltering plant or oil refinery to be located there. Light industry/creative industry certainly fits well, and I am all for it as an employemnt center. However, I don’t see any reason to exclude residential from it either, nor to push it into a luxury market.

    “What am I missing? Why can’t zoning be used to protect the CEID?”

    I’m not even talking about the property being developed. Look at the Pearl – it was abandoned by industry long ago, before any development occurred! The fact is that centrally located desirable land has a higher value, making it less likely that a traditional industrial company would want to spend the extra money to move there, versus cheaper land along a major transportation route. For instance, if you were a semiconduct mfgr who needs to build a 40 acre campus, where are you going to locate? Zoning be damned, there as just basic economic consderations in play that have much more influence than zoning ever will.

    Again, I’m going to say why do we want our most pedestrian-friendly land served by transit, parks and other amenities utilized for heavy/polluting industry? The city will benefit much more by using that for high-value uses such as high-end residential and commercial office space.

  21. First off, you see urban residential development in the central city as “uneeded and uneccessary.”
    I couldn’t disagree more. More than a million people will be moving to portland over the next two decades and they all have to live somewhere! We should be increasing the density of the central city in order to grow. Succesful and lively cities are dense in the center!

    Or else we could not increase that density, and have those million people not move here. I mean, why is that constantly described as both inevitable and a good thing? And for whom is Portland in its current size not “lively” or “successful” enough? Property developers? Transplanted Los Angeleans? Or the people who’ve lived here all their lives?

    Elsewhere in the world, smart communities successfully limit their growth, but here in Portland there’s a panic to throw up condos fast enough to house all the projected new citizens …

    This is the same argument that the freeway builders give: the traffic is growing, we have to grow the freeways to accomodate it, or else there will be congestion! But congestion will always happen when there’s growth; congestion is our growth-limiting tool. Likewise, if we put some hard limits on the number of new bedrooms that can be built in Portland in a year, we’ll gain control of our density destiny.

  22. Yes, there are a lot of nice things that could be done in the Beautiful Rose City to improve transportation… And lots of big federal dollars could be spent like that legendary gold from the King’s coffers…And the Willamette could turn into the River Avon…And we could raise taxes onward to eternity…

    Let’s look somewhere else besides I-5 for a way to improve traffic flow between SW Washington and NW Oregon. Like the BNSF corridor and I-205.
    Until removal of the 1-5 is well though out–and not some part of a string of endless “fixes”– it is better to leave it alone. I have already been tossing out for comment the BNSF/Western aterial/NW Front Ave/SW Barbur Blvd route as an alternative corridor–one which could have commuter rail built into it.

  23. A “OK, but freeways don’t pay property taxes into the general fund”

    B Neither do public waterfront parks, the Eastside Esplanade or bicycle lanes and trails. Property taxes don’t pay for freeways either, but property owners are assessed for parks. Motorists and motorized freight carriers pay for freeways in addition to subsidizing the infrastructure for non-self-supporting modes of transport with user assessments like fuel taxes and weight per mile taxes for trucks. Furthermore, unlike parks that have an optional use recreational impact, freeways have a direct positive impact on the economy as it relates to the movement of people and goods, and providing family wage jobs.

    Some 20 years ago I went to Chicago on Amtrak with a friend to attend a convention. After the convention, a number of people in the organization opened up their homes so participants could visit and view their collections related to the convention. Several of us from out of town rented a couple of cars and drove all over the Chicago area. One of the things I found interesting was that many of the bridges over the freeways and turnpikes had structures, services for motorists, like gas stations (I am not sure how the storage tank system worked) and fast fool restaurants located right on top of the highway.

    It seems like a portion of this concept could be applied in Portland and Oregon. Sort of putting a roof over the highway, but still having an “open air” highway. This is different than capping a freeway like I-405 that is already below street level. Capping a freeway is just another way of building a tunnel that would have safety disadvantages. It is also fairly obvious those who want to cap freeways and put them in tunnels are the anti-car activists that want to make the driving experience anything but pleasant, and probably wouldn’t be paying the costs either. However, building a roof with open sides over a ground level freeway like I-5 could make sense if that roof can be leased for commercial purposes. Widening existing bridges and overpasses where they cross other highways to form the roof would probably cost far less than tunneling. Moving the freeway and the associated cost acquisition for the property is simply too costly.

  24. One would think that $5 billion would buy some sort of high speed commuter rail connecting Salem-Woodburn-Wilsonville-Portland along the I-5 corridor. A reasonably priced train that would travel at 80-100 MPH with only four stops could alleviate traffic congestion and make both Salem and Woodburn viable bedroom communities for families that don’t wish to live in $750,000 / 600 sq. ft. condos in the city.

    Something like this could be up and running within a decade rather than some 20-30 year pipedream that involves more costly engineering and more expensive “livibility” nonsense. The new eastbank neighborhoods will just be bought by retirees, empty nesters, and wealthy singles like the South Waterfront and Pearl. This will leave families and moderate income earners no more choice than they have now: long and inefficient commutes from the more affordable suburbs.

  25. We don’t have near the density in the Eugene-Vancouver BC corridor to make high speed rail pencil out, but its coming.
    Check out http://www.riverfrontforpeople.org for more information on the potential for the “second half of Portland” in the second half of its second century. I love Phil Goff’s drawing with the Marquam Bridge approach as an elevated park.

  26. “Elsewhere in the world, smart communities successfully limit their growth …”

    i would like to know where this has occurred; where have communities limited their growth? and how did they do it? and what does the result look like?

    i am really curious. how does a community limit growth and remain dynamic, and economically successful?

  27. It is actually impossible to ‘limit growth’ and not allow people to move to a city. If they really want to come here, they will. It is against the constitution of the US to outright ban people from other states to move to Portland.

    Most of the growth does NOT come from Oregonians reproducing.

  28. i totally agree. philosophically, i believe that limiting the freedom of movement of people over earth is one of the greater tyrannies, however, politically i am a little more practical–people should be at least as free as capital.

    i think the best way to ‘limit growth’ in a region is for that region to descend into stassis, for its economic impetus to dry up. but mykle said that it has occured, and i have heard many suggest a desire for the same goal, including a prominent letter to the editor in the tribune, and an odd marriage of left-wing environmentalists, and right-wing xenophobes.

    so i’ll ask again: where?

  29. “I love Phil Goff’s drawing with the Marquam Bridge approach as an elevated park.”

    I’ve frequently suggested that the piers and massive lower crossmembers of the Marquam Bridge would easily support a streetcar track. This would be a teeny-tiny fraction of the weight that is already there. Moreover they conveniently align with both the “Harrison Connector” and OMSI, the southern terminus of Eastside Streetcar. That would give commuter rail a cheaper alternative to the Caruthers Bridge, which in turn obligates us to the $200 million plus Downtown Mall. Presto, a Loop! But we’re going to spend a cool billion, adding in the five mile long Milwaukie MAX. Is it seismically safe?

    I don’t know, but how safe would a tunnel be, with masssive ground movement? Hundred of travelers trapped underground as the water pours in. I think this is a comparison worth investigating. Perhaps the first thing a study should consider. Safer, where? Above ground or below?

  30. I like the idea of saving the money for the streetcar bridge by using the lower level (Southbound I5). Place viewpoints and private businesses on the top level.

    I would think that a tunnel would be able to handle a major earthquake better because the tunnel would move with the earth instead of being ripped apart and shaken like a bridge would be above ground.

    Hopefully, a tunnel under the river and under the Lloyd District is the only tunneling done to save costs.

    I understand that the city council voted to go forward with the recommendations and to expect a report in one year or less on the master plan. The big issue was getting some fixes in sooner (at I5/I84 and at the Marquam Bridge) without wasting the money.


  31. Tunnels can be constructed to be quite seismically sound… look at the Transbay Tube for BART under San Francisco Bay… not even a true tunnel so much as a big pipe buried in a muddy trench, so far surviving several major quakes. (Not that it wouldn’t be extremely scary to be down there during a quake, for sure…)

    Does anyone here know the seismic specifications of the westside MAX tunnels? How do those specifications compare with modern bridge, overpass, and viaduct construction?

    – Bob R.

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