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San Francisco’s Composting Ordinance Turns Waste into Wine

By Jeanne Roberts

Oct 12, 2009

Starting next week, food-waste recycling will be mandatory in San Francisco. No more banana peels and uneaten Brussels sprouts entombed in plastic in a landfill — they'll now be headed to a more useful place.

Under the city's new Universal Recycling and Composting Ordinance that takes effect Oct. 21, all residents must carefully sort their trash into recyclables (cans, bottles and paper), trash, and compostables, meaning food waste, plant trimmings, soiled paper and other items that can be converted to compost.

In keeping with the city's ultra-green image, the San Francisco Board of Supervisors voted 9-2 earlier this year to pass the ordinance in an attempt to do away with landfills and incinerators entirely — and, in the process, to cut emissions of greenhouse gases. Landfills produce , a global warming gas that is 23 times more potent than carbon dioxide.

Food waste composting isn’t new. Many of San Francisco’s residents and restaurants already send some 400 tons of food scraps to Recology's Jepson-Prairie in Vacaville.

The now makes it mandatory. And the penalties — $100 per violation for residents, $500 for businesses — are significant enough to encourage even the recalcitrant, or merely lazy, to get in step with Mayor Gavin Newsom's goal of zero waste by 2020.

The city already diverts almost three-quarters of waste away from its landfill. According to Robert Reed, a spokesman for San Francisco collectors Sunset Scavenger Co. and Golden Gate Disposal & Recycling Co. (both subsidiaries of Recology), the food waste-to-compost is an idea whose time has come.

Want to see which communities added food scrap composting just in the last 30 days? he asks. Type "food scrap compost" into Google and click "news" at the top of the page.

The results are surprising, and Reed is right. Composting is a valuable tool that experienced gardeners use to enrich soil worn out by repeated plantings. Compost encourages microbial activity, improves soil structure and enables better water retention. In and around San Francisco, the priceless compost from Recology is used to enrich organic farms and vineyard soils, or offered for resale to garden centers and landscapers.

Compost isn’t just good for soils, though. It's also good for the environment, because making compost removes materials from the waste stream that, in landfills, contribute to the formation of greenhouse gases.

Of course, the same thing happens in a good compost pile, but during composting, the anaerobic digestion is to three weeks as compared to 30 years, meaning fewer gases are released. As Paul Hepperly, research director at the non-profit organic farming , notes:

"Conventional farming — tilling the land, using commercial fertilizers, etc. — puts 3,700 pounds of carbon dioxide in the atmosphere per acre per year. Applying compost, which helps grow 'cover crops' that draw carbon in part from the air, returns 12,000 pounds of carbon a year to the soil."

Bob Shaffer, of Soil Culture Consulting in Glen Ellen, concurs. Shaffer, who has 35 years of experience as an agronomist, horticulturist and viticulturist, and consults with dozens of Bay Area vineyards, explains:

Plants are the ultimate builder of soil humus, and create the ultimate form of stored carbon in reference to natural or farmed soil. It is the roots that have the greatest ability to form and store carbon in soil, because they:

• turn into humus more easily compared to other forms of organic matter

• grow out in "swarms" in soil and deposit carbon in a large area, over time

• deposit carbon in soil while they are alive by exudation and by soughing off cells

• deposit carbon in soil when they die

• deposit carbon deep in soil where there is no other practical means to place carbon

So how effective is applying food scrap compost to growing cover crops? Shaffer says:

"On a scale of 1-10, we would rank compost as an 8, or even 10, depending on the quality and placement of the compost."

Wine growers and organic food producers are less interested in the carbon capture mechanisms of compost/cover crops than the results — vines heavily laden with prime wine grapes and State Fair-sized vegetables full of nutrition without the use of fertilizers.

Cline Cellars is a prime example. Located on a 350-acre estate in the Carneros District, and best known for its superbly zesty Zinfandels, Cline Cellars has also been using the compost for a no-till viticulture that relies on cover crops for about a decade.

"By regularly adding compost to vineyard soils you dramatically improve water retention, fertility and tilth. In addition, you disperse in the soil a magnitude of beneficial micro organisms which help the vines fully develop and produce full flavored grapes and thus, premium quality wine," says owner Fred Cline.

Cline Cellars also runs an organic farming operation called Green String Farm on 140 acres outside Petaluma. The farm, only part of which is under active cultivation at any one time to support sustainable agriculture and crop rotation, also uses the compost to grow about 100 acres of cover crops to nourish the soil for future food production.

Still, there’s no denying compost produces greenhouse gases. So the East Bay Municipal Utility District (EBMUD) has created a to generate electricity from the methane gas produced by food waste decomposition through . Methane, when burned, releases less carbon dioxide than any other hydrocarbon fuel (i.e., natural gas, oil and coal) and it produces garden-ready compost.

The program is believed to be the first of its kind in the country. EBMUD engineers have been testing and refining it since 2006, when the EPA gave the utility $50,000 to study the process. The district plans to begin selling energy to the grid sometime in 2009 and estimates it will get 4.5 megawatts from the food waste-to-electricity program alone.

There are, of course, some iconoclasts who say no amount of diversion of food waste, or any waste, will do much good as long as the waste stream is of industrial waste, or what Mother Jones writer Kevin Drum calls GNT, for Gross National Trash.

On the other hand, there’s Eleanor Roosevelt’s philosophy, which suggests that it is better to light one candle than curse the darkness.

Here’s your candle, Kevin.


See also:

Food Production Can and Should Step Away from the Fossil Fuels

Eat Local: Cuba's Urban Gardens Raise Food on Zero Emissions

Solving Kenya’s Food Crisis, One Indigenous Crop at a Time

USDA Census (Part I): Small Farms on the Rise in America

Organic Farming Yields Far Better Crop Resistance and Resilience

Taking Personal Responsibility for Climate Change

(Photos: Compost bin/iStock; Vineyard/Cline Cellars)


I wish more cities would do

I wish more cities would do this. The composting program in San Francisco is really a step ahead of anywhere else.


Anaerobic decomposition is not "Accelerated" by composting.

Rather what happens is you get a whole different kind of decomposition, aerobic (oxygen requiring) decomposition, assuming you turn or tumble your compost that is. If you just let it sit there unaerated you get the same anaerobic decomposition (though, less than if it was truly sealed in a plastic bag, since air still interacts with the sides of your pile, if not the center).

If your compost smells, it means you've got Anaerobic bacteria happening, and you're doing it wrong, either not enough turning/tumbling or oxygen. Or the wrong ingredient mix (too wet, too much nitrogen).

When you do it right, and get the aerobic bacteria, which do not emit the odor.

Composting and Greenhouse gases

"Still, there’s no denying compost produces greenhouse gases."

Please check your facts; I believe that this depends on the type of composting being done.

I don't believe that Vermicomposting (i.e. composting done by worms) emits much in the way of greenhouse gases, but is slower.

Thermophilic composting (whereby the compost temperature is greatly raised through reactions with bacteria, etc) probably does though.

We Need YOUR Help!!

It is clear to me that you as well as your readership honor the small steps that every person makes in greening their home and being the stewards of their little corner of the planet. I applaud Mayor Newsom and his goal of "zero waste" by 2020. But I ask you as fellow citizens of this planet, what do you think is really meant when you said "The city already diverts 3/4 of its waste away from it's landfill". By "diversion of waste" what you really mean is that it is shipped to another landfill next to someone elses home who has their own waste to deal with.....but now they also have Yours.
Perhaps the term diversion does apply to the miriad ways in which creative and industrious people are developing technologies that create biofuels and other green biproducts from the waste that we create. However, we won't ever accomplish zero waste and eliminate those tons per annum of methane gas produced in our local landfills if we don't deal with it locally.
Your reduction of methane production through composting is only a genuine reduction when the waste that YOU produce does not decompose over a 30 year period of time in a landfill somewhere else.
Right now that "somewhere else" is a beautiful area of virgin desert 25 miles from my home where I raise my sweet daughter as conscientiously as possible in regards to Global health and Community. Help us by understanding that this is everyones responsibility. Don't let Recology turn MY HOME into a "diversion" for your waste!

Recology/Winnemucca Landfill

San Franiciscans are commended for the role they play in leading our nation in recycling.

As this article notes San Francisco has a goal to "... do away with landfills and incinerators entirely — and, in the process, to cut emissions of greenhouse gases.... Landfills produce methane, a global warming gas that is 23 times more potent than carbon dioxide. "

Citizens of Winnemucca, NV agree. No landfills. San Franciscans may be interested to note that Recology, their partner in recycling (and, general garbage management) is pushing forward on a proposal to ship 4000 TONS, PER DAY, 5 DAYS PER WEEK of Bay Area (not just Bay Area) via rail to start a landll at Jungo Road, part of the Black Rock desert. The shipments are currently targeted to go on for 95 YEARS. The shipments will include hazardous waste. The landfill, if capped at these estimates, will grow to the size of a 20 story building.

Citizens of Winnemucca do not want this landfill. Get involved and help us out:

Get informed:

Nevadans Against Garbage Facebook Group:

Sign the online e-statement (any age, any location)

The US address version of the e-statement:

European addresses version of the e-statement:

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