For four months this summer, the paper that central Iowa residents dutifully placed in their curbside recycling bins ended up at the landfill where it was buried with the rest of the metro's garbage.

It wasn't a mistake.

Mid America Recycling, the company that processes the metro's recyclables, says it couldn't find anyone willing to take the paper.

Across the county, cities are having trouble offloading recyclables since China began tightening its standards on the materials it would accept nearly two years ago.

In Des Moines that meant about 20 tons of paper a day ended up in the landfill during the summer, said Mick Barry, president of Mid America Recycling.

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“That’s where the markets have deteriorated to,” he said.

Des Moines' recycling program has always been subsidized by the city's solid waste fees, Public Works Director Jonathan Gano said.

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But how much the city loses on the program is growing.

Recyclable materials once garnered hundreds of thousands of dollars on the open market — they brought in $320,000 for Des Moines in 2017 — but that revenue has plummeted.

Des Moines' recycling program is expected to run a $50,000 deficit next fiscal year.

The city is preparing to raise the solid waste fee it charges customers by 2 percent next year, in part to cover this loss.

“It’s still good public policy,” Gano said. “It still preserves airspace at the landfill, which is an expensive resource, and we wish to preserve its ability to preserve our garbage needs in the future.”

Metro Waste Authority, which handles recycling for the metro's suburbs, has also seen costs increase. The fee paid to Mid America to process recyclables went up $18 per ton to $65 in October.

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That will cost MWA about $25,000 more each month.

Leslie Irlbeck, MWA's public affairs manager, said the agency so far has not passed on that extra cost to customers.

But "how that impacts the residents who live in the suburbs longer term is still unknown,” she said.

Des Moines, which pays Mid America $47 per ton will likely face a similar increase when it renegotiates its contract, Barry said.

What is driving the cost increase?

China was once the destination for much of the industrial world's recyclable waste.

But in 2017, the country began imposing new rules on the amount of "contamination," or non-recyclables, that it would accept in shipments, according to a CBS News report.

China's imports of solid waste dropped by 57 percent year-over-year in the first quarter of 2018, Xinhua, a state-owned news agency, reported.

That has created a surplus of recyclable materials, which have plummeted in value, making it harder for companies like Mid America to find U.S. facilities willing to take them.

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Recycled paper was worth around $100 per ton six years ago, Gano said. Now, it’s around $30 per ton, which doesn't cover the $47 per ton processing fee Des Moines pays Mid America.

According to MWA, 60 percent of the material it collects from recycling bins either has no value or negative value.

Mid America sells its processed paper, which makes up about 40 percent of the Des Moines metro's recycled goods, to paper mills in places like Indiana, Wisconsin and Oklahoma.

And while the quality of the paper coming out of Des Moines is high, Barry said, those mills can get paper cheaper from other cities that are closer, spend money to clean it themselves and still come out with a profit.

“We’re now all competing for the domestic markets,” Irlbeck said.

'We’ve got to get people educated'

Barry said contamination has played the primary role in rising recycling costs.

People are putting trash in their recycling bins and that trash must be removed before it can be sold.

“We need to start talking more about this,” Barry said.

Trudging through a pile of garbage outside Mid America's east-side facility last week, he pointed out some of the items pulled from Des Moines recycling bins.

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Garden hoses, kiddie pools and an old lawn chair all must be removed by MidAmerica employees.

Soon it will be holiday lights that fill metro recycling bins, he said.

“We’ve got to get people educated,” said Alan Schumacher, president of the Iowa Recycling Association board of directors. “It’s in dire straits. It’s ugly.”

Roughly 11 percent of items that end up in MWA recycling bins is garbage, Irlbeck said.

Des Moines and MWA both audit recycling bins and leave behind “oops” notes when they find trash, but more needs to be done, local recycling officials say.

“Today, everything is taken away, which then enforces to people, ‘Oh, wow, I must be recycling all the right things,'" Irlbeck said.

Barry said the recycling industry is reaching a transition point, signaling the end of single-stream. He predicted an increased use of mixed-waste processing, in which processors take in both everyday waste and recyclables and sort them, is on the horizon.

According to a 2015 report from solid waste consultants Gershman, Brickner & Bratton Inc., mixed-waste processing could yield the recovery of more recyclable materials — and higher revenues — but its coexistence with the trash could lead to higher contamination rates.

“Recycling, as being done today, is not economically feasible,” Barry said.

What can I recycle?

Find out what items can be recycled where you live by visiting the city of Des Moines' website or the Metro Waste Authority's recycling guide.