A small milky bloom that was discovered July 10 in a section of the Pootatuck River adjacent to Commerce Road was determined to be nontoxic and not harmful to the Class A trout stream, according to the Land Use Department's Deputy Director of Planning Rob Sibley.

After receiving notification of a milky substance in the river, Mr Sibley and Senior Land Use Officer Steve Maguire investigated.

Mr Sibley said the small plume resulted after nontoxic substances were forced out of a blocked curtain drain at St Rose of Lima Church during construction activity occurring on that site.

"They are replacing the storm water system at St Rose, and they have a number of footing drains that surround the property to keep the church dry," Mr Sibley said. "One of them was clogged, and they had to put a pump in to be sure water from the footing drains didn't compromise the storm water system."

That pumped out and discolored water ran down Church Hill Road toward Commerce Road, into a storm drain and into the river.