The Portland City Council is expected to agree Wednesday to expand a

to all the city's single-family homes and complexes with no more than four units. The rules will take effect Oct. 31.

How will it work?

Residents will toss unwanted food -- coffee grounds, bones, rotten vegetables, uneaten meat and even discarded pizza boxes -- into the green carts now used only for yard waste. Haulers will increase pickups to once a week from every other. The good news? Residents can still throw yard waste in with food scraps, and the city will give all residents kitchen pails to collect scraps.

Why is the city doing this?

Finances and environmental concerns are factors. It's cheaper to compost than dump garbage. Diverting food waste from landfills to composting facilities reduces carbon emissions. And the end product can be reused -- and resold -- as fertilizer. "It's cost-effective, and it uses a waste product to develop a valuable commodity," said

Susan Anderson

, director of Portland's Bureau of Planning and Sustainability.

What's the downside?

To hold down costs, garbage service will switch from once a week to every other week. Critics worry that reduced service won't work for large families or residents unwilling to compost. Supporters say folks who compost will have far less garbage; the city estimates that food waste makes up about 30 percent. Weekly pickups of food waste and yard debris should minimize concerns about odors and pests such as rats, city officials say.



What do participants in the pilot program say?

Residents in four Portland neighborhoods have been testing curbside composting since last year. "It took a little while to get used to," said Carrie Moses, who lives in Northeast Portland's Roseway neighborhood. "I wish we could still have our regular garbage every week," she added, saying it's difficult when guests visit and add to the garbage.

Where else does this happen?

Portland will follow

and

. In Oregon,

rolled out curbside composting in July 2010. "We're not exactly cutting-edge here, folks," Mayor Sam Adams said last week.



Where will the food scraps go?

Nineteen garbage haulers operate in Portland, said Bruce Walker, the city's solid-waste program manager. They take yard and food waste to one of four transfer stations. Waste then goes to two composting facilities,

near North Plains, owned by Recology based in San Francisco, or

near Corvallis, owned by Republic Services of Phoenix, Ariz. Recology and Republic both sell the compost to gardeners and others for $20 a cubic yard.

How will this affect garbage rates?

As of Wednesday,

-- which operates two of the transfer stations -- was still negotiating prices. However, Paul Ehinger, director of solid-waste operations at Metro, expects the cost to be in line with city estimates. Walker said last week that 80 percent of residents will pay the same for service. For most, that's $23.70 to $28.50 a month -- though some with larger cans could see a $2 a month increase. Those who need to jump to a bigger can because of the less-frequent garbage service will pay more. Someone moving from a 32-gallon to a 60-gallon cart, for example, would see a $7 increase to $35.90 a month.

What will the city spend to implement this?

City officials could spend up to $1.1 million to introduce the program. Some of that money will go toward temporary staffers to answer residents' questions. "We are ready to get out there and make this system work," Walker said.



What's next?

Portland would like to run a separate pilot program to collect food waste from larger apartment complexes, perhaps next year. Multi-family residences account for about 25 percent of the city's population.

Find more on Portland's curbside program at

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