In California’s Central Valley, farmers have been coping with diminishing water supplies, rising water costs, and other impacts of the ongoing drought. At CalCAN’s Climate and Agriculture Summit in March, Tom Willey of T&D Willey Farms discussed the impacts of drought and how he has responded to water shortages on his farm in Madera County.
Since 1981, Tom has grown an array of organic vegetables on his 75-acre farm with his wife Denesse. Specialty markets, restaurants, and Community Supported Agriculture (CSA) members enjoy Tom’s produce. Until recently, Tom served as Slow Food USA’s governor for the Central Valley, and he also advocates for sustainable agriculture through his writing, speaking, event organizing, and his monthly radio program, “Down on the Farm.”
SL: You spoke at our Summit in March about challenges regarding the drought and water issues. Now that we’re in the heat of summer, what’s the status on your farm and the region generally?
TW: We lost a shallow well on the farm in the past month or so, and we had to come up with an alternative supply. Shallow wells are going dry all over the county. It’s impossible to drill a new one or deepen an older one unless you’re already on a waiting list for a driller—most are booked for up to a year or two. On our farm, we plumbed into our deeper (500 ft) irrigation well. This well is designed to pump 1,000 gallons per minute, but at the moment, performance is closer to 650 gallons per minute. What I can say is that another dry winter would definitely spell disaster.
SL: You also spoke about practices like building soil health, irrigation, and crop selection. Can you tell us more about your response to the water shortage this summer?
TW: What certainly works is putting a lot of organic matter into our soils. Even though we’re in a hot and dry climate, we’re able to hold our soil organic matter at about 1.5 to 2 percent. And the average around here—if you’re not doing intensive cover cropping or composting—it’s about 0.5 to 1 percent. We’ve noticed the water holding capacity of our soils has significantly improved over the past 20 years. We’re able to capture and utilize much more of the winter rain.
And we narrowed down our cropping program. Two years ago, we grew 50 different crops, but it just doesn’t make sense to use precious water resources to grow crops you’re only trading dollars on. Now we’ve moved away from what’s marginally profitable, and we grow between 35 and 40 annual crops.
SL: You mentioned you grow summer crops that are high producing, which helps reduce water demands.
TW: Right. We grow staked and trellised high production crops during peak water demand—tomatoes, peppers, eggplant that can be grown more intensively. In the summer, we’re farming the least amount of acreage, about 50 percent of our land, while still generating high revenues. Right now we water three times a week, and during the winter, maybe once a week. Most of Madera County is in permanent crops, so most growers fallow during winter. We do the opposite. It helps balance our demand for water.
SL: In addition to improving water retention, building soil health can increase carbon sequestration. What are your thoughts on that?
TW: Well, I’ve done a lot of reading on this, and I think a lot of work needs to be done in developing tools and measurement devices to demonstrate long-term carbon storage below the first foot of topsoil. If we can do that, I certainly think it’s appropriate to reward farmers who can maintain higher levels of carbon in their soils, particularly here in California where we have a cap-and-trade program with a carbon market. In particular, we need to look at orchards and vineyards that practice little to no tillage—they have a large potential for carbon storage. It’s more challenging to get farmers in low rainfall areas to do no till and cover cropping because of water availability and cost, which shows why we need to reward farmers for these practices.
SL: At the Summit, you mentioned that dry years we’re seeing now will be offset by very wet years in the future, during which time we should flood the valley to recharge groundwater.
TW: In the latest California Agriculture, an important article describes a statewide survey of farmlands, identifying which are most appropriate for wintertime flooding to recharge groundwater. Insightful people are realizing we will start seeing cycles of dry years and wet ones with near-flooding. Even if we get a wet year with normal rainfall, we won’t have normal snowpack, so we need to redesign our system to figure out how to capture that winter rainfall.
I would certainly consider seasonal flooding on my farm. We would sacrifice a certain amount of acreage to do our part and hopefully other farmers would do the same. It has to be a concerted effort. Incentives have to be created for farmers. We can no longer pump indiscriminately, so we need to give more attention to recharging groundwater.
The audio of his March 2015 Summit talk can be found here.
This article was originally published Sept. 24 on the California Climate & Agriculture Network website.