Update: Port of San Juan is open, 3000 containers of relief supplies have been unloaded by Crowley Marine alone, but there's too much debris on the roads to get semitrailers out of the port yet. Diesel fuel is in stock at tank farms but not getting distributed because roads are blocked.
Bulldozers and front end loaders will deal with that, but not instantly.
Update 2: Crowley has 10,000 containers stuck at the port, but only 20% of the truck drivers have been located. With cell service down, nobody can call them. Getting Diesel to fuel stations is a problem. 11 tankers are inbound, and 100 fuel trucks have been sent out from San Juan. But damaged gas stations without power can't use the fuel.
Bulldozers and front end loaders will deal with that, but not instantly.
[1] https://www.wsj.com/articles/puerto-rico-port-reopens-but-re...