SEATTLE -- Local wastewater treatment officials said they are seeing an increase in the amount of non-biodegradable items clogging up their pipes, and some new "flushable" products on the market are causing expensive problems downstream.

For those who live in Seattle, everything that's flushed down the toilet ends up at the King County Wastewater Treatment Plant in Discovery Park.

Once toilet paper arrives, it's mostly broken down, but lately, officials are finding a lot more that isn't.

Wastewater Manager Pam Elardo, said with the increasing popularity of disposable wipes, they're seeing and increase in unwanted debris, particularly wipes that are marketed as "flushable" or "100 percent bio-degradeable".

One hand wipe product claims the sheets are safe for sewers, because they "break-up after flushing."

"They're good products for disinfection, but they don't break down by the time they get here," said Elardo.

The wipes, along with other non-biodegradable items such as condoms and tampons, have to be filtered out and dumped into a container.

Estimates are that wipes make up half of the waste that has to be taken to a landfill about twice a week.

"I don't understand why people put debris in their toilet when they could just as easily put it in their garbage can. And I think people have this illusion that it's free to put it in your toilet, but you're paying for it through your sewer rate," said Elardo.

Not only does it cost about $100,000 a year to haul the waste away, but disposable wipes can also clog wastewater pumps, such as one at a pump station in Richmond Beach.

A pump there seized up when a wad of wipes and other items got stuck, causing an employee to take the pump apart to get the sewage flowing again.

As a result, wastewater treatment officials said if there's any question about whether something should be flushed, put it in the trash can, not in the toilet.