I've lived in Grants Pass since late 2001 and have been puzzled by one thing: the tap water will leave reddish/brownish stains in the bottom of the shower or the bottom of a water glass. The stains wipe off with just a flick of your finger or a light swipe with a cloth or sponge. What the heck is this stuff?

I've lived in Grants Pass since late 2001 and have been puzzled by one thing: the tap water will leave reddish/brownish stains in the bottom of the shower or the bottom of a water glass. The stains wipe off with just a flick of your finger or a light swipe with a cloth or sponge. What the heck is this stuff?

— Ed R., Grants Pass

As far as Grants Pass water treatment officials can tell, Ed, it's either a mix of sediment or run-of-the-mill rust — iron oxide — that can collect along the sides of older, galvanized pipes lacking contemporary concrete lining.

But don't worry, it's not hazardous to your health.

"It's just inconvenient, and we're the first ones to admit it," said Jason Canady, water treatment superintendent for Grants Pass.

Bob Hamblin, utility field superintendent for Grants Pass water and sewer, said his office has received calls about similar incidents before.

"It's probably a handful every year," Hamblin said.

Sediment and rust layers in water tend to pop up more often in pipes that see sudden heavier flows of water and buff the sides of the pipe. Water flow in an area following a fire that was extinguished, for example, can show this, as the demand on the pipes increased.

But not to worry, there are solutions.

The first step is to let the faucets run for five or 10 minutes. If it doesn't clear up, wait an hour and try again.

"Usually, it clears right up," Hamblin said.

There also is a specialized filter that can be applied to stop the particles. Canady said they can be picked up at home improvement stores, but he recommended going to a specialized professional instead.

"You want to make sure it's sized correctly for your house," he said.

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