Thursday, August 26th, 2010

The Physical Evolution of Infrastructure

Thinking about recent posts on the Metra bridge project and long term parking meter leases, I was reminded of a conversation I had with Professor David Solzman at UIC. He made an interesting comment that we need to find a way to create infrastructure that can physically evolve over time at reasonable cost.

Our fundamental approaches to many things haven’t changed that much, despite big changes in the world. We still create major buildings to last for the ages, even though they’ll be functionally and technically obsolete quite rapidly. We treat infrastructure as a one shot build deal, where to change, upgrade or even repair it later is a hugely invasive, costly, and difficult proposition.

Maybe instead we should operate on the consumer electronics paradigm, where we focus on low cost, innovation, and a shorter term product cycle. That might be one way. Another is to create more modular or flexible architectures that allow things to be changed or replace in a much easier and cheaper manner. With things like sewer and water pipes, this might be difficult. But it’s an area worth studying.

One of the big challenges we face is that the lifespan of our investments can exceed the realistic planning time horizon given the ever faster cycles of change. This can leave us stuck with albatrosses for decades. I think, for example, of all the cities building deep tunnels for stormwater management just as we’re on the cusp of being able to use new green techniques to do this in a better way and at lower cost.

I won’t pretend to even have the problem fully framed, much less have a solution. But this is an area that deserves significant study and consideration.

Topics: Transportation

16 Responses to “The Physical Evolution of Infrastructure”

  1. Roland S says:

    Interesting topic. Infrastructure albatrosses aren’t the dire problem that you imagine, though. We’re pretty resourceful creatures and we don’t like to leave things sitting abandoned if we can help it.

    The freight railroad tubes in Chicago were obsolete the day they were finished, but many decades later they allowed telecom companies and power utilities to very quickly and easily lay phone, fiber optic, and cable TV lines to service the entire Loop. This is, I suspect, one factor in why downtown Chicago is one of the biggest data/telecom hubs in the world.

    I’m still waiting on the streetcar tunnels, but I think that’s just a case of forgetfulness.

    Deep Tunnel projects, if they are rendered obsolete, will find some other important use in the future. I’m pretty sure of it.

  2. Aaron Brown says:


    You bring up an interesting question – any idea if the streetcar tunnels are still usable for transportation? The tunnel under Washington St. would be a way to get that E-W transitway built.

  3. Alon Levy says:

    Following privatization, the major Japanese railroads have focused on something like what you suggest. They haven’t compromised on infrastructure costs, but they focus on building technology to be low-maintenance, even at the cost of shorter depreciation cycles. For example, they design trains that need fewer repairs and damage the tracks less.

  4. Chris Barnett says:

    “Deep Tunnel projects, if they are rendered obsolete, will find some other important use in the future.”

    Mushroom farm or wine cellar? More seriously…

    Small-scale hydroelectric generation system.

    Drinking water pipeline/storage system.

    (In Chicago’s case, #1 and #2 could be combined if the tunnel were connected to Lake Michigan.)

  5. Aaron Brown says:

    Also, there is a proposal (albeit unlikely for now) to re-use the Deep Tunnel for transit:

  6. west town ed says:

    Am I missing something here? What streetcar tunnels? The only thing I can think of is what appears to have been a tunnel big enough for streetcars under the Chicago River on LaSalle Street which can be seen from the north side but does not appear to emerge on the south side of the river — a victim of the building Wacker Drive? Are there really others?

    Also, as I understand the Deep Tunnel, storm water currently flows into it but there is no place to store the water until it can be pumped out so when the tunnel is full, water has to be released into the river and then into the lake. Regardless the idea that we can dry these tunnels out at an untold and unrealistic cost so that they can be used for transit is lunacy.

  7. west town ed says:

    Correction: I think the tunnel I referred to in the first paragraph is on Clark Street not LaSalle Street. I hoped to confirm this on Google Maps/Earth but the satellite photos on both (which appear to be the same) were taken early morning and the shadows of the buildings obscure the details on both streets.

  8. Aaron Brown says:


    Quick summary of the streetcar tunnels here:

  9. Curt says:

    Aaron I think I remember you posting about a trip to Spain where you observed that city utilities were buried under sidewalk pavers in the sand/gravel and that it facilitated an ease of maintenance.

    Perhaps similar thinking could apply to other areas.

  10. Brian W says:

    I am glad that stormwater based green infrastructure is usually the less expensive alternative to building “grey infrastructure” such as expensive underground tunnels. So often it seems like doing the “green thing” like installing green roofs or solar power is intially more expensive and therefore less likely for a utility company to choose. However, I think most Cities and utilities dealing with Consent Decrees are trying to figure out the right mix of green and grey infrastructure that will result in the lowest long range costs. In fact, I think that stormwater engineers are lightyears ahead of traffic engineers in every way.

  11. Patricia Tice says:

    My son’s best friend is moving from Florida (where we are) to Toronto next week. They fully anticipate connecting at least weekly over skype. I couldn’t have even imagined that when I was his age. I moved across a county and even a telephone wasn’t good enough to maintain relationships then. His parents converse with friends in Asia regularly.

    The question I am increasingly asking has to do with how our infrastructure needs are likely to change in the next 30 years. We obviously don’t have the issue with manure in New York that was expected at the turn of the last century, but we have replaced those issues with different ones.

    Until recently, technology has changed the fringes of our lives, but we have yet to see what it does to the workplaces and social interactions we have now. We are currently in the vehicular equivalent of the 1930’s and we don’t have the slightest clue what these new types of technology will do to the way we live.

    Transportation and energy distribution may see the largest infrastructure impacts (in different directions), but the social sphere is likely to experience the biggest changes. In the end, what if the metropolis vision fails, not because the freeway are too expensive to build, but because the centralization inherent in a downtown core is no longer necessary? Bike friendly sprawl may really work well when you eliminate the work trip, especially if you can get freight and logistics worked out. Living in a village of 100 on a mountain may be no more isolated than living in downtown NYC. It may even be more conducive to real community.

    “Even the very wise cannot see all ends…”

  12. Thanks for all the comments.

  13. Roland S says:

    The surprise I get when I bring up the subject of the streetcar tunnels just proves my point about how everybody’s forgotten about them. If somebody in power were to be reminded of their existence, I’m confident that we’d see at least some conceptual plans for re-use.

    I believe all three are still intact, although the LaSalle Street tunnel had its southern approach cut off when they built the Dearborn St Subway (Blue Line) in the early 40s. The tunnels were big enough for two streetcars to pass each other, and modern buses or light-rail trains are approximately the same size.

  14. Aaron…….Those global city ratings, done by A.T. Kearney and the Chicago Council, are published in Foreign Policy magazine, indeed (as you note) without explanation of the metrics or criteria, because Foreign Policy chose not to include this. Kearney and the Council will shortly publish all this (will keep you posted when it appears). Perhaps any comments on home cooking could be postponed until you get all the facts, huh?

  15. stunoland says:

    Louisville KY is about to become the first and possibly only city to ever expand an elevated waterfront expressway. Although there is probably not a way to build short term highway infrastucture the city should at least build a design that at least allows for future alterations. If a context sensitive at-grade I-64 with multiple pedestrian overpasses is built the city can decide at any point in the future to add a few turning lanes and rename the road something other than I-64. Many people believe the current design and funding plan of the downtown Ohio River Bridges Project to be the biggest urban planning mistake of the 21st century and we could really use some help preventing this economic disaster. Aaron, i know you have written about 8664 extensively but an article highlighting the destructive economic and cultural consequences of the downtown ORBP would be very helpful to those of us fighting this impending disaster.

  16. Nathanael says:

    “Another is to create more modular or flexible architectures that allow things to be changed or replace in a much easier and cheaper manner. With things like sewer and water pipes, this might be difficult.”

    Oh no, no, it’s not difficult for sewer or water pipes.

    The key insight is that “heavy concrete” and earthmoving should only have to be done once. The civil engineering structures should be designed so that the less-long-lasting, more-subject-to-change stuff inside them can be replaced without replacing them.

    In other words, build large ducts and chases for your utility pipes and then you can replace them without ripping everything up. Don’t just bury the pipe in the ground, put it inside an accessible “outer pipe”.

    Different rules apply in the countryside and to certain types of planning, where the key consists of preserving hard-to-reproduce natural areas and installing civilization in harmony with them. This applies to stormwater management, of course, and to parkland in cities.

    In most construction in the cities and in the connections between the cities, the key is to do the civil engineering once (and do it right) and allow the various things which might run along a transportation corridor to be added and removed without further civil engineering.

    Buildings have a similar character. Build a heavy superstructure which will last, but such that the uses and partitions of interior space can be changed without great trouble — adaptive reuse should be in the mind of the initial builder.

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