(FAIRPLAY- The International Shipping Weekly, November 25, 1999; founded 1883, London England)

Desalination requires huge amounts of energy (far more than many transport options).  It is therefore limited to regions where energy is cheaply available.  It also produces a wide array of waste products (sludge, processed chemicals, concentrated brine), which are difficult to dispose of.  This is particularly poignant in the Caribbean and Mediterranean where pollution of the surrounding sea would deter the very tourism that the water is needed for.

Desalinated water still contains a number of salts that are considered a public health concern, and cause excessive corrosion of pipes.  The plants take up expensive coastal land, which is a concern in regions such as California and some Caribbean islands.

Furthermore, desalination technology is mature, so there is little hope of it becoming cheaper without finding cheaper energy sources.  Moreover, many projects to date have under-priced themselves intentionally to promote the technology, so in the future prices can only rise.