THE BRONX - A new environmental effort aims to bring the Bronx River back to life.

Experts dumped 120 tons of clam shells into the Bronx River today. The layer of shells will house the river's homeless oysters.

The process is intended to make the Bronx River cleaner. Experts say oysters extend the ecosystem and filter water.

The project is a joint effort between scientists, nonprofits and government agencies. It's the largest effort of its kind.

Scientist Jim Lodage says the Bronx River was once known for its oysters, but they died off due to pollution.

For more on the clam shells, watch the clip to the left or click News 12 Extra on Optimum TV channel 612.