Salem, Oregon, officials say the city’s water is safe to drink after testing for blue-green algae. The city is testing its water seven days a week.  

Toxin levels change dynamically day-to-day, said Peter Fernandez, Salem’s public works director. 

“We’ve seen days, especially up at the reservoir, where toxin levels are through the roof and the next day the toxin levels are way, way low,” he said. “We’ve just got to keep looking.” 

Fernandez said that’s due to warm weather and the region’s changing environment due to wildfires.

“We see the water in the reservoir, certainly in the reaches, getting warmer and we’ve had spectacular fires up there what, five, six, seven years ago, so, the combination of the warm water with the nitrogen and the ash that runs into the water, we believe is what’s causing the algae,” he said.

Testing the water at the reservoir acts as an “early warning,” Fernandez said. That water feeds into the city’s water treatment facility where it’s filtered and treated with chlorine, fluoride and other elements.  

Depending on algae levels, chlorine might be increased for treatment, and then reduced to normal levels to offset toxins. 

Last year, Salem had to send water from its reservoir for testing out-of-state; now it has the resources to test in-house.  

“We went from three days to really same-day results,” Fernandez said. “As we’re doing testing, we’re able to make decisions really very quickly.” 

Fernandez said the city is keeping a close eye on algae levels but even if toxins were to get into drinking water, “you have to consume it for 10 days in a row for it to have a detrimental effect.” 

“We have time and we will report whatever the results are,” he said. “But this isn’t a situation where if you have a drop of it, it’s going to cause any detrimental effects.” 

The city will continue to post updates on its website.