The foam was first spotten at the end of March 2017 and covers large parts of the lake. Ducks have trouble swimming through it, that's how thick it is.
Authorities were informed by lakeelsinore.us about the mysterious substance. Depending on where the wind blows, the substance spreads over larger parts of the lake.
Lakeelsinore.us asked city authorities to take samples in order to determinate if it is safe to swim and fish.
Mayor Bob Magee was concerned for the public and wildlife had the foam tested. He told lakeelsinore.us that it is a natural fenomemon.