In 2011 — the early days of crowdfunding — three designers raised over $41,000 to assist them in building a self-filtering public swimming pool that will float in New York's East River. Two years later, they are back. Archie Lee Coates IV, Jeffrey Franklin, and Dong-Ping Wong have launched their second Kickstarter campaign for + POOL, offering 70,000 engraved filtration tiles to backers to help fund the project's $15 million construction budget.

If every tile is claimed, the entire $15 million budget will be funded

In the two days since it launched, + POOL has raised $65,000 of its $250,000 goal. If it meets its target, the team will build a small + POOL "Float Lab" in the river in August and test its filtration materials. The entire $15 million construction budget would be funded if it sells all of the tiles, making it the biggest Kickstarter campaign ever.

The 70,000 tiles (starting at $199) offered to Kickstarter backers will make up the deck, walls, and the floor of the pool, filtering the river on which it floats. Given its size, the project's creators warn that budgets may change and gaining approval from the necessary authorities may take time. Aiming for a 2016 launch, the team hopes it has enough time to finish its research, design and build the structure, and gain the necessary permits — giving New Yorkers a clean and safe public pool in which to swim.