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MSc in Major Programme Management

MSc in Major Programme Management


Likelihood of Mexico wall completion is 'virtually zero'
Building a wall would be one thing, says Bent Flyvbjerg, but maintaining it quite another.

Donald Trump has announced plans to fulfill his election pledge of building a wall along the United States border with Mexico. Will work start on this wall and will it ever be completed? I think the answer to these questions is probably and absolutely not.

The plan appears poorly thought out and there are no real details on how it is to be built. Like all megaprojects, it carries the inherent risk of huge cost and time overruns, and of being unfit for purpose.  Despite being built around the world for centuries, the vast majority of large infrastructure projects still suffer cost overruns and delays.  There are few modern precedents for a wall of this magnitude. If you combine a lack of available experience and knowledge with very complex political, legal, financial and environmental issues, the chances of it being built to budget and time, working according to intention are slim.

The finances of the proposed wall do not add up. Donald Trump has suggested that construction of the wall will cost in the region of $10 billion. The likely construction costs would be much more, in the region of $15-$25 billion.  On top of that will be operations and maintenance costs, which could run into the billions each year. In all likelihood, construction would take years, surpassing Trump’s presidency and taking us into a world where issues of immigration and security, which this wall is promised to solve, may be very different from what they are now.


Bent Flyvbjerg View profile

Bent Flyvbjerg is the first BT Professor and Chair of Major Programme Management at Oxford University. He works for better management of megaprojects and cities. He also writes about the philosophy and methodology of social science.