Pumping seawater would relieve a symptom of the problem without addressing the cause. It would also introduce new problems.

• The transportation of the water would require  a lot of energy, and a lot of infrastructure both to supply the energy and to house pumps and other equipment. It would require maintenance too.
• The water would have to be desalinated, which requires more energy, infrastructure and maintenance.

We don't think this kind of project is very useful because

• The resulting water would be extremely expensive for the end users, or leave them permanently dependent on outside funding.
• Water would still be scarce, compared to the amount of water that is pumped inland by forests.
• It would only solve one problem, and only for those who could afford the water. The underlying causes of desertification and other problems, such as poverty, are not addressed.

People using the system would be dependent on technology they have no control over and on a small number of technologists and the managers of the system for their livelihoods. If there was no other possible solution, this might be acceptable. With individual permaculture systems as part of a wider project encompassing the entire region they would be able to mainain their autonomy while solving many other problems than just water shortages. It would also cost vastly less in terms of initial money donated and be done without the beneficiaries incurring any debts.