There is land at the back of the exhibit, just out of range of the image in this photo, but the majority of the available area for the snakes is covered in water. There are two anacondas and quite often one will be entwined amongst the branches and be half-in and half-out of the water, and in the photo one of the snakes can be seen in the bottom right-hand corner of the pool.
Thank you for the information. It looks like a superb display, but the amount of land space for anaconda is questionable. Perhaps its not really crucial to their care.