The substance surfaced sometime Wednesday, April 27 in Passaic's Hughes Lake in Third Ward Park.
City officials began flushing the water, and Mayor Hector Lora tells Daily Voice it will take approximately five days for the color to return to normal.
The water's change of consistency and color was caused by “diatomaceous earth,” something used in pool filtration systems, Lora told NJ Advance Media.
Further, officials found the YMCA had not flushed its pool's filtration system in about two weeks, the outlet said. A check below manhole covers confirmed the substance was flowing into the park from somewhere in Clifton, Lora told various news outlets.
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