Marin Voice: 'Carbon farming' and Marin's drought

CALIFORNIA is experiencing one of the worst droughts on record.

Here in Marin County, family farms and ranches are facing devastating economic losses without water in their reservoirs or green grass in their pastures. This historic drought has led to concern about the future of our state's agriculture as climate change affects weather patterns in unpredictable ways.

Over the past decade, Marin has witnessed an agricultural revival with local farmers and ranchers diversifying their operations, direct marketing to Bay Area consumers, and providing healthier food choices for people who live here. This revival not only means a thriving local food system, but also the preservation of the landscape and rural character that are at the very heart of what makes Marin special.

There is a lot at stake in ensuring that our farms and ranches can withstand droughts, now and into the future.

That's why the work being done by the Marin Carbon Project is so critical.

What started out as an experiment on Marin farms led by UC Berkeley scientists to find out whether or not soil could store more carbon — and it can, big time — has turned into an important means of safeguarding our farms against drought.

What might not be common knowledge is that soil carbon holds a very large amount of water.

Adding carbon, in the form of compost, to agricultural soil increases its water-holding capacity, which means it not only holds more rainwater in the soil, but also helps maintain the water in our streams and reservoirs.

To get technical, hydrologists measure the degree to which plants are unable to obtain the water they need to grow as "climate water deficit" (CWD).

Statewide, that deficit is expected to increase by at least 5 million acre-feet in the next century due to climate change and prolonged periods of drought. That will almost certainly drive farms out of the drier regions of the state.

However, if compost applications and other carbon beneficial farming practices are adopted, the increase in soil water holding capacity could reduce CWD by more than 25 percent.

That means that we could preserve farms in today's agricultural regions.

Marin is expected to fare relatively well, due to coastal influences, in the face of the expected drying of the state. But, as we are witnessing this year, Marin's farms already face major climate-driven challenges.

Carbon farming offers the most practical and effective strategy for drought preparation and drought resilience available to local family farms.

As I write this, the Marin Carbon Project has launched three carbon farms in the county. This past fall, compost was applied to more than 100 acres of land and our partners are now monitoring the results.

Our hope is that the farming practices being modeled will provide a template for carbon farming that can be widely adopted.

The pending results, both in terms of taking carbon out of the atmosphere and building water retention and soil fertility, are very promising. Carbon farms could be the farms of the future, safeguarding our farms and the food they produce against the devastating effects of droughts like this.

The Marin Carbon Project is an exciting and ambitious undertaking that wouldn't be possible without the support of many partners: MALT, UC Cooperative Extension, Marin Resource Conservation District, county Agriculture, Weights and Measures, Marin Organic, Carbon Cycle Institute, USDA/NRCS and UC Berkeley.

Go to to find out more about the project.

Jamison Watts has led the Marin Agricultural Land Trust since January of 2013. He is the former executive director of the Northern California Regional Land Trust and worked as a wildlife biologist and environmental consultant.