Dear All,
please note the effort that Brutus and others are putting into their very valuable "make the best of things stance". They are doing their best under extremely difficult, if not impossible circumstances.
Clearly establishing and maintaining the tropical garden is impossible under the circumstances. There is obviously no point in wasting money on elaborate watering systems when the water supply itself is in doubt. There has already been a huge waste of money on unsustainable plants being carted away in skips.
With the best will in the world -no soil + no water = no garden.
Perhaps some small specimen areas can be maintained at critical points and other features introduced on the land.
Possibly some of the hard exercise features that are now appearing along various seafronts can be incorporated. Perhaps even some outdoor elements of the missing sports centre too.
You have had something of a shock and a steep learning curve, no doubt and I for one wish you every success.
However I do not believe you can make any sort of garden, except perhaps a rock garden, without topsoil. It is that which will differentiate a garden from the natural scrub of the area.
Unfortunately as a non-owner I cannot personally assist with your admin, I was not even allowed to attend a meeting.
Best wishes and make the miracle come true.
Regards
Norman