Water Apocalypse

It all started not with floods...but with rains. The rains lasted for weeks, then months. Some regions of the Earth have not seen the sun for six months.
Rivers overflowed their banks, dams collapsed, cities sank, but the ocean still remained within its usual boundaries.
Scientists have noticed a strange pattern: the volume of water on the planet has been increasing faster than could be explained.
It seemed as if the ocean itself was beginning to rise from the depths of the planet.
When sea levels began rising by tens of centimetres per year, governments declared a global emergency.
To stop the disaster, the Thalassa Project was created. It was a network of huge ocean stations that monitored and stabilized the water. Humanity believed that the catastrophe had been stopped.
Three years after its launch, a malfunction occurred and overnight the system began to operate in reverse mode, accelerating the flooding.
Then most of the continents ended up under water and after some time the ocean began to cover almost the entire planet.
The surviving humanity lives on: floating cities, old oil platforms, giant colony ships and rare mountainous islands.

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