Updated with additional details.

Officials in the cities of Mountlake Terrace and Edmonds on Wednesday issued a health advisory for Lake Ballinger after raw sewage was found in the City of Edmonds stormwater system that leads to the lake.

The advisory, which states that no fishing or swimming is allowed, is due to “an ongoing investigation of possible contamination on the Edmonds side of the lake.”

City of Edmonds Acting Public Works Director Phil Williams said city crews doing work in the area Tuesday discovered. raw sewage in the stormwater system and an investigation began into possible sources, with assistance from the Olympic View Water and Sewer District. So far, the city has not been able to find an origination point for the sewage and there is no estimate as to how much of it has entered the lake.

We’ll update this story as more information becomes available.