The project is looking to get $200,000 in funding through Kickstarter, which would be just the first phase. That money would go to create a Lowline Lab, an interactive exhibit/experiment to grow plants underground from September to February (the harshest time of year) to test the project's feasibility.
The Lowline founders describe their inspiration as "Mannahatta — a verdant vision of the city before modern civilization," which will have edible plants "and a science fiction palette of greenery forming stalactites, stalagmites, and whimsical passageways."
Lowline would be housed inside the abandoned 107-year-old trolley station under Delancey Street in the Lower East Side, which has been untouched since 1948. Check out the Kickstarter page for renderings of the park and a video about the technology of diverting sunlight to create an underground ecosystem.