UPDATE (June 2, 1:13 p.m. PT) — After about four days under a drinking water advisory for Salem’s vulnerable populations, the city has declared water safe for all residents.

The decision to lift the advisory was based on water samples taken on Wednesday and Thursday. The city says the results confirm that toxin levels are below health advisory levels and that water is now safe to drink.

The city first issued the advisory on Tuesday after water samples showed low levels of cyanotoxins caused by algae blooms in the Detroit Lake.

Detroit Lake flows downstream into the North Santiam River, the source of the city’s water supply. It’s believed to have been the first time the potentially harmful toxins made their way into the distribution system of an Oregon public water system.

Gov. Kate Brown declared an emergency Thursday and activated the National Guard to distribute water at several locations in and around the city.

The advisory and the resulting furor among residents and city officials alike raised questions about what the city knew about the toxins when, and whether it worked fast enough to notify residents. 

The toll of the panic has Salem officials rethinking not only how they communicate water quality readings, but where the city actually gets its water.

“Long-term, we feel that we need a second source of water,” said Peter Fernandez, the city’s public works director. That could come in the form of sinking new wells or eventually even building a new filtration plant on the Willamette River.

The city said it will continue to collect water quality samples and update the community. Salem already conducts routine, voluntary testing for cyanotoxins. Testing is not required under the federal Safe Drinking Water Act.