I did the 30k last year, so I'll try to remember as best I can.
Shade wise there are a few sections on the Clarendon section where there is cover under the trees and and some towards the end around the back of the racecourse. I'm doing the 50k and had to go out and buy a running hat yesterday.
As for water stations I think there were about 6 or 7 on the 30k course. I can't remember 100%. I aim to walk through each one and make sure I take on extra fluid at each one.
Hop this helps.