Tropico 5's first expansion, Waterborne, will be available from December 17th for $19.99.
The expansion, which you can see a trailer for below, is set against the backdrop of El Presidente wanting to take his rule out to the sea. To this end you'll be experiencing water traffic and larger coastal areas for the first time in the series.
New structures include production buildings like Oyster and Kelp farms, tidal power plants and floating apartments. Military submarines will also make an appearance, alongside six new scenarios.
As for what you'll be able to do with these new off-shore buildings, a press release explains:
"Organise and coordinate transport to structures like the kelp and oyster farms, construct tidal power plants as an eco-friendly alternative to nuclear power and build gorgeous floating apartments if you’re running out of space on the island! Launch military submarines to bolster your naval forces or create an exotic bathysphere attraction to compliment your bustling tourist paradise."