Rain water is quite abundant due to regular typhoons and monsoon in South China Sea. Sea water desalination would compliment rain water collection.I love the trees, it's a really nice touch. Planting trees in that sort of number tells everyone you're here to stay.
I wonder how often you have to water the trees. My mum had a colleague who was in the PLAN (retired now) and was working in the area of water purification for SCS island bases back in the days. Of course back then the bases were tiny, some of them no more than buildings on stilts and the fresh water supply were all collected rain water purified by machines that this colleague help design, supplemented by supply ships. With bases now on this scale I wonder if they have to run reverse osmosis machines and desalinate the sea water.
I see damages to tile roof of some buildings, possibly caused by strong wind from typhoons and monsoon. They should replace those roof tiles with solid concret roof.