The current population of Earth is just over 7 billion people. By 2050 that is expected to rise to 9 billion people and 11 billion by 2100. Unless we find a new place to put things are going to get pretty crowded.

Some very smart people, including Mars One and SpaceX CEO Elon Musk, are working on creating colonies on Mars within the next 20 years. Getting a new planet to populate would help considerably. However, there is still lots of room on this planet as well. 70% of the Earth is covered by oceans and that is where the story turns to Japan’s Shimizu Corporation.

The company, which also has plans for solar power generating stations in space, lunar bases, man made green island cities and other things that look like they belong on the cover of science ficiton novels, has unveiled plans for a “Deep Sea Ocean Spiral” city.

The elaborate plans on the company’s website cover not only engineering but the environmental impact, the economy of an underwater city, lifestyle, food sources and other details of life under the sea.

There is no indication that they are set to begin construction anytime soon but the company’s website contains a fascination collection of ideas and food for thought. Say what you like about the present condition of humanity but we live in an era of big ideas.