Competition between utilities like ports I was reading about the frequent congestion in US ports and the resulting effect on the US economy. I feel there are unique features to this setting. When ports face congestion, they levy charges, and these are transferred on to the buyers by the shippers. On top of this, costs of delayed reception of goods are also borne by the retailers only. The only 'catch' for ports arises if the congestion is so high that firms shift to air transport or reroute through a farther port and incur road transport expenses. 

Are there papers which model the economic interactions like competition between ports, or the interactions between firms, ports and labour unions?
In America, on the West coast, unions negotiate a common contract:


  Ironically, the International Longshore and Warehouse Union is a
  beneficiary of the same forces that are killing unions everywhere
  else: Its workers are the folks who unload the stuff that comes in
  from abroad. Those workers are sitting right at the bottleneck through
  which all that foreign competition flows to the U.S., and due to some
  smart planning by the union in earlier decades -- such as insisting
  that the West Coast ports would bargain as a bloc so that they can't
  play different locals against each other -- they can cork that
  bottle anytime they want. That gives them the ability to extract a
  little tariff on all that trade. Their rake-off is a tiny fraction of
  the overall flows, but that still translates into substantial sums for
  the few thousand workers who are holding onto that cork. The more
  trade, the better the concessions the ILWU is able to extract -- and
  the worse workers in other unions do.


Where Have All Our Wages Gone? by Megan Mcardle 

There used to be a pre-anti-trust era railroad cartel in the USA:


  The [Joint Executive Committee (JEC)] was a cartel formed by the
  railroads which controlled eastbound freight shipments from Chicago to
  the Atlantic seaboard in the  I  88os. The agreement was publicly
  acknowledged, as it preceded the passage of the Sherman Act (1890) 
  and the formation of the Interstate Commerce Commission (1887). ...
  The JEC cartel agreement took the form of market share allotments
  rather than absolute amounts of quantity shipped. Firms set their
  rates individually, and the JEC office took weekly accounts so that
  each railroad could see the total amount transported. Total demand was
  quite variable, and the actual market share of any particular firm
  depended on both the prices charged by all the firms and unpredictable
  stochastic forces.


On the Incidence and Duration of Price Wars (Porter (1985))