San Francisco Mayor Gavin Newsom today signed the nation's first mandatory composting policy into law. The ambitious rule will help the city achieve what are arguably the most aggressive organics waste targets in the U.S.

At the Farmer's Market in front of the San Francisco Ferry Building today, San Francisco Mayor Gavin Newsom signed a first-of-its-kind rule requiring all residences and businesses to compost their organic waste. The tougher new composting standards were approved by the San Francisco Board of Supervisors in early June by a vote of 9-2.

"San Francisco has the best recycling and composting programs in the nation, and we’ve already attained an impressive, and first in the nation, 72 percent rate, because of them," said Mayor Newsom.

Newsom's office recently conducted a waste-stream analysis and discovered that about two thirds of the garbage people throw away, approximately 500,000 tons annually, could have been recycled or turned to compost. San Francisco already converts over 400 tons of food scraps and other compostable discards into high-grade organic compost every day.

"It’s so nutrient-rich that the final product is almost jet black in color," writes Newsom today at CleanTechnica. The high quality of compost is "snapped up by farms and vineyards across the Bay Area, we can barely keep up with the demand," adds Newsom.

By requiring all residences and businesses in San Francisco to sign up for the city's recycling and composting collection programs, Newsom hopes even more organic waste will be diverted from landfills and made available as a valuable commodity used in sustainable regional agriculture.

City officials say they'll give residents time to adjust to the new rules but could eventually start levying fines of up to $1000 for organic waste scofflaws. No fines are specified in the ordinance, but there is a cap of $100 established for residences and businesses that generate less than one cubic yard of refuse per week. Fines higher than $100 may still apply to businesses and to landlords of large apartment buildings who refuse to offer recycling and composting opportunities to tenants.

Newsom said a primary goal of the mandatory recycling ordinance, which was co-sponsored by Supervisors Ross Mirkarimi and Chris Daly, is to get recycling and composting happening in buildings where it is not currently provided.

"I believe that composting will become second nature for Americans, just like sorting bottles and paper," added Newsom. "It will take time, but I believe mandatory composting will spread across the country—improving the air we breathe and reducing our need for landfills."

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