Looking at the bits on Google Satellite, the Daily Mail graphic is a tad misleading, the viaducts link a tight corner in the north east of the bay, then run as a single viaduct across the whole bay. I can see why they picked the location, the northern and western edge of the bay is littered with massive paddy fields that extend miles inland and the two headlands to the south are full of development. Now I'm aware Chinese planning law doesn't favour the individual

but the development looks like ports, petro-chemical and lots of new high rise residential. It also looks like the main bay crossing links into a major route to the south west and there looks like some clearance is going off inland to the eastern end...
Although there is some tarmac on the south-west approach indicating 4 lanes in each direction, I'm always mindful of how you make improvements at later stages, in the same way as we can't realistically widen Westway or the Midland Links - they are improvement cul-de-sacs, although the Chinese would probably just drain the bay and fill it with more factories and houses.
I used to have a desire to visit China, I suspect it would be like visiting a 1950's London Docklands with a bit of 1920's Sheffield Lower Don Valley - yuk !