I have no doubt there's corruption.

There's a lot of inefficiencies too.

I think you might like this article: How to build back under budget (maybe) | The Economist

>But unfortunately the agency drawing up the contract does not have enough qualified staff to conduct a full review of construction proposals. The lowest bidder wins the job, as is typically the case in America. After winning, however, the contractor quickly tacks on additional costs, and the government is again in over its head. Unable to manage such a big project, it ends up relying on contractors and consultants who botch key segments of the Wilson line, requiring expensive do-overs. Inter-agency turf battles and co-ordination problems worsen the situation.