It certainly is possible for a construction project to be so intricate and so involved that only a certain number of companies would have the resources—human and otherwise—to undertake it. This is one of the reasons you have a pre-qualification stage.
But It would be possible--I understand that it didn't happen in this case--for an employee or agent of the purchaser to define the requirements so specifically and with the objective in mind that only one company would be able to do it. For instance, I have seen situations in the case of the purchase of a product—an electronic product—where the specifications were essentially word-for-word the specification sheet of the manufacturer. In situations like that it becomes quite obvious that the specifications were tailored to direct the work to that manufacturer.
In the instant case, I believe there were in fact a number of qualified bidders, and the work was awarded to the lowest responsible bidder. Again, I could be wrong on this, but this is what I get from reading the newspapers, which of course are never wrong about anything.