Creating a left bank mooring on the Thames

As we sped downstream past Bourne End, between Marlow and Maidenhead, on the left bank was a brand new riverside mansion, with de rigeur solar panel and off-line mooring. What do you call these single-boat-sized chunk-out-of-the-garden moorings? They must have a name, but it escapes me at the moment.

I read somewhere that to determine which bank is "left" and which "right", as often applied to the Seine in Paris, you visualise yourself standing upstream of where you want to describe. Then if it's on your left, that's the left bank.