Officials in Portland, Oregon, have decided to empty nearly 40 million gallons from the city’s primary reservoir for drinking water because an individual urinated in it. The decision marks the second time in three years that the city has flushed large portions of its water supply because someone peed in it.

The latest dump comes after 19-year-old Trey Michael McDaniel was caught on a video surveillance camera urinating in the Mt. Tabor Reservoir Number 5 in Southeast Portland. He and two other 18-year-old men had trespassed into the area, and all three were subsequently cited by police and banned from the area for 30 days. Criminal charges are pending.

City Commissioner Nick Fish said the potential health risk was very small. But because some risk remains, he added, the decision was made to flush 38 million gallons from the lake.

“I didn't have a choice. I don't have the luxury of slicing it too thin when there's a potential risk, however small, to public health,” he told The Oregonian. “Frankly, it’s one of those calls where you know you’re likely to be criticized no matter what. The professionals who report to me all said, ‘Dump the water. Don’t take any chances.’ It’s the conservative but correct call.”

Politics may have factored into Fish’s decision. He is up for reelection in May.

Also, the city commissioner “has been made the public face of questionable bureau spending and rising rates by advocates of a ballot measure that would shift control of Portland's utilities from the City Council to an independently elected water district board,” the newspaper reported.

Similar events unfolded in 2011, when another person, Josh Seater, peed in the Mt. Tabor reservoir. That incident prompted the city to dump 7.8 million gallons of drinking water.

Critics called the decision three years ago an overreaction on the part of city officials.

Toxicologist Alan Boobis was quoted by the BBC News as being “flabbergasted” by the move. “In a healthy person, urine is sterile. It’s something we can say with confidence—it’s not going to have any impact on anyone whatsoever,” Boobis said.

-Noel Brinkerhoff

To Learn More:

Man Caught on Tape Urinating in Mount Tabor Reservoir; Portland Water Bureau Testing Supply (by Anna Griffin, The Oregonian)

Commissioner Nick Fish Says Emptying Mt. Tabor Reservoir 'Conservative but Correct' Call (by Anna Griffin, The Oregonian)

8 Million Gallons of Drinking Water Go to Waste Because a Man Urinated in a Reservoir (by Noel Brinkerhoff and David Wallechinsky, AllGov)