There's been a lot of buzz about the water bureau's decision to flush

because a teenager

.

The incident has raised a lot of questions. We're here to answer them.

Is it really worth draining all that water?

"Yes, and here's why: My customers expect that they will receive water that hasn't been deliberately contaminated," said Water Bureau administrator David Shaff. "I can do that. That's it."

Shaff said the city has plenty of water, and draining the 38 million gallons won't interrupt service or strain supply. There are other contaminants the city can't do much about, he said, but the bureau can keep tap water pee-free. "If I can, why wouldn't I?" he said.

Does a trace amount of urine pose a health threat?

Shaff said he thinks there is a "very minimal risk," but deferred to the county health department, which has not yet returned request for comment.

Don't birds poop in that water?

Yes, they do. Small mammals take a dip sometimes, too, and pollen blows into the water from the trees. Those natural contaminants are a key part of the Environmental Protection Agency's justification for a rule that requires

. Portland is scheduled to disconnect the open-air reservoirs on Mt. Tabor from the drinking water system by the end of 2015.

Shaff said there isn't much the bureau can do about those natural contaminants in the meantime, and that they don't pose a serious health risk.

Doesn't the water get treated before it comes to my tap anyway?

Sorry to break it to you, but no. The water you see in the reservoirs is the water you drink and bathe in. There is a grate that catches large debris, Shaff said, but the water is not treated or filtered between the reservoir and your tap.

Where will the 38 million gallons in Reservoir 5 go?

The water will be drained via the sewer system, which means it will be treated at the Wastewater Treatment Plant and then discharged into the Columbia River.

Can the water be used for something else?

It isn't logistically feasible to use the water in Reservoir 5 for irrigation or other purposes, Shaff said. The water is being drained through the sewer system, which means it can't go anywhere but directly to the treatment plant. To purchase the water in Reservoir 5, a company would have to pump it directly out of the reservoir, which Shaff said would cost a lot of money.

How much will it cost the city to drain and clean the reservoir?

Nothing but time, said Shaff. The bureau does not need to hire a crew or pay employees overtime to get the cleaning done quickly. Shaff said he will have to estimate a monetary cost for the Multnomah County District Attorney, but that the cleaning won't affect the bureau's budget.

-- Melissa Binder