I think you will find that the centre of the lake is in RWD's tenement as this is the lowest elevation in the area. Water usually flows to the lowest point which I imagine is the centre of the largest expanse of salts i.e. the centre of the lake. Most of the channels are draining into the lake not away from it.
You can confirm this using Google Earth's stand alone application which includes an elevation parameter in the status bar.
Cheers
DYOR
