ORONO, Maine (AP) — The National Science Foundation is giving $100,000 to help with a University of Maine citizen science project geared at protecting the water quality of lakes.

The project began in 2015. The university says the grant will help extend it into next year and beyond.

UMaine says Maine lakes contribute about $4 billion to the state's economy through recreational and other uses. They are also experiencing a decline in water quality.

UMaine says one of the biggest concerns is nutrients stimulating the growth of aquatic plant life, which results in depletion of dissolved oxygen. That can harm the health of the ecosystem and lead to higher treatment costs for lakes that are used as a source of drinking water.

The university's project involves developing a "lake vulnerability index."