indeed, sotos, filtering the sea water to remove particles would be helpful, in any case. pipes are expensive because they demand a right of way, a 'foot print' if you will, on the land. starting small means trucking.
However, it is possible for the Government on the other hand to configure a process which takes into account the energy we can get from the salt water when it is heated by the sun as it travels uphill to the high points of the island, so that the energy required from other sources to desalinate it (for other uses) is managed more efficiently, while grey water can be added to the process along the way, sub stations may provide for an alternative use of the water with salt but clean.
...in any case this issue is complex because the use of fresh water is still necessary to maintain a level of 'saltiness'.