San Francisco leads the nation in food composting and it now appears there may be even more benefits than we realized.
San Francisco was the first major city in the United States to offer citywide composting of food scraps. It started with a pilot program in 1996 and has become the model for the nation.
"Now, this program is being replicated in 300 other cities across the United States," says Robert Reed.
Reed is with NorCal, the company that pioneered San Francisco's compost program.
As part of that program, food gets thrown in a bin with yard waste and is picked up once a week. It is then composted at a giant facility in Vacaville.
In most places this is not what happens.
Most food scraps end up at the dump where food decomposes and creates methane, a greenhouse gas 23 times more potent than carbon dioxide.
"Greenhouse gases go along with garbage," explains Reed.
Although, if food is turned into compost instead of garbage, the amount of methane is cut and it actually nourishes the Earth instead of harming it.
"We've now gotten so skilled that we are able to use modern composting techniques and preserve a lot of the carbon in the finished compost," Reed says.
In the simplest terms, too much carbon in the air is bad, but carbon in the dirt is good.
"This is the dawn of the age of new agriculture, where we are carbon-based and we realize that the most precious nutrient in the soil, in a way of speaking, is carbon," says Bob Shaffer, a soil specialist in Sonoma County.
Carbon is critical for microbes that live on plants roots.
"When we return carbon to the soil, the microbes use it. That, then protects the plants and causes the plants to grow better," Shaffer says.
A lot of compost is made with green waste, which includes yard trimmings and agricultural waste. However, when food scraps are used, the compost gets even better for the plants.
"Obviously it's our food, so it has a lot of nutrients in it," Shaffer points out.
Shaffer showed ABC7 around the Green String Farm, one of many Sonoma and Napa farms and vineyards using compost made with food scraps from San Francisco. He explained that one key to getting carbon and nutrients back in the soil, is to plant a variety of cover crops with different types of roots.
"It's hard to pull it up. It's got a big root system. It's been lying out here where there's a lot of compost. Grass plants in general and grain plants have very fibrous root systems. They very quickly can trap nutrients and access nutrients in the soil. And, with compost around them you can see the size that this root system has gotten, you notice it doesn't want to fall apart," Bob said describing the method.
The crops do not get any chemical fertilizer and they are packed with nutrition. It is the kind of result that made the executive chef of one San Francisco restaurant a true believer.
"We now recycle or compost over 92 percent of our garbage. So, only five to eight percent is solid waste garbage," says Steve Scarabosio, Scoma's executive chef.
Cutting down the amount of garbage also cuts down the garbage bill. Still, only about half the city's homes and restaurants are participating in food composting.
"The biggest issue we have is with what people call the 'yuck' or the 'ick' factor. The material, if you leave it in your kitchen, separated by itself for too long, will start to smell," NorCal Waste President Mike Sangiacomo says.
Composters recommend getting the food outside to a compost cart as soon as possible. Then, there should not be a smell problem. And, the planet will be healthier.
"Don't just throw things away. If there's another use for them let's help find a way to do that," says Sangiacomo.
Other Bay Area communities have also launched food composting programs including Alameda County, San Ramon, Fremont and some parts of San Jose. San Carlos has just become the first city in San Mateo County to launch a similar program.
Written and produced by Jennifer Olney