In 2006, a strain of E. coli bacteria contaminated fresh spinach from California’s Salinas Valley, the main growing region for leafy green vegetables in the U.S. It is unknown how the bacterium came in contact with the spinach, but it led to a national outbreak of E. coli-related illness. Nearly 200 people across the country became sick.

As rivers and streams from Salinas Valley drain into Monterey Bay on the central coast of California, indirect effects of the outbreak have also flowed downstream. Voluntary conservation practices that spinach growers had previously put in place under guidance from resource managers – such as wooded buffer areas between fields and streams to reduce agricultural runoff – have now been removed by the growers. The removal came under pressure from spinach-processing companies and other buyers, who wanted to avoid any chance of E. coli contamination from animal feces. In turn, the reversal of the conservation practices is leading to greater runoff into Monterey Bay. Resource managers are faced with finding solutions to address two needs simultaneously: food safety and conservation.

Working cooperatively with growers

All of Monterey Bay lies within the 21,000-km2 Monterey Bay National Marine Sanctuary (MBNMS). (Maps of the sanctuary are available at MBNMS management has long recognized the influence that Salinas Valley agriculture has on downstream water quality. “We have partnered with many groups and individuals over the last decade to implement voluntary strategies to protect and enhance the quality of water flowing off farm fields into the sanctuary,” says Lisa Lurie, Agriculture Water Quality Coordinator for MBNMS.

These partnerships largely occur under the umbrella of the Agriculture Water Quality Alliance (AWQA), a regional initiative. AWQA includes MBNMS staff as well as personnel from the U.S. Department of Agriculture, several regional resource conservation districts, farm bureaus, academic researchers, industry groups, and NGOs. Together they have supported Salinas Valley growers in implementing practices to prevent erosion, reduce the use of agricultural chemicals, and protect wildlife. Many of the voluntary practices involve allowing vegetation on and around farmland. Prior to 2006, most growers in the valley had adopted at least one conservation practice under AWQA guidance. These practices were estimated to prevent 258,000 tons of sediment from entering the sanctuary annually.

When the E. coli outbreak occurred, it spurred the development of food safety programs that were in conflict with conservation goals. “Farmers were caught in the middle,” says Lurie. Although there is no evidence that the removal of vegetated buffers from farmland reduces the risk of E. coli contamination, and it remains unclear that the E. coli contamination site was even in a field (as opposed to farther along the food-handling chain), some buyers and processors urged farmers to cut down the buffers and leave the soil bare.

AWQA partners are now working to develop solutions to address both food safety and conservation at once. They have applied several strategies:

  • Education and outreach: The Resource Conservation District of Monterey County and the U.S. Department of Agriculture have conducted training sessions on the conservation aspects of food safety to food safety professionals. AWQA has trained state conservation personnel on food safety considerations for conservation planning.
  • Research: Scientists at the University of California are investigating factors that affect E. coli growth and survival in agricultural soils. Other AWQA partners are evaluating the effectiveness of water quality practices in reducing the concentration and migration of bacterial pathogens in irrigation runoff.
  • Technical assistance: AWQA partners are providing technical and financial assistance to growers to improve the efficiency of their use of water and fertilizers. Making such uses more efficient is another way to reduce runoff, but without raising fears of E. colicontamination. It also saves money for farmers.

“By keeping sediment on the fields, farmers are keeping the pesticides and nutrients on the fields, too – all of which benefits water quality in Monterey Bay,” says Lurie. “Water quality is essential to ensuring protection of marine resources. And effective watershed management is critical to marine ecosystem-based management.”

For more information:

Lisa Lurie, Monterey Bay National Marine Sanctuary, Monterey, California, U.S. E-mail:

AWQA website:

Article: “Crops, ponds destroyed in quest for food safety”, San Francisco Chronicle. 2009.

Article: “Food safety and environmental quality impose conflicting demands on Central Coast growers”. California Agriculture magazine. 2008.

BOX: Tips on working with growers to implement voluntary conservation practices on their farms

From Lisa Lurie, Agriculture Water Quality Coordinator for the Monterey Bay National Marine Sanctuary:

  • Building relationships is key. Reach out to the leading land-based resource conservation and agricultural groups in your watershed. Through these types of partnerships you can build a network with innovative growers who are leaders in their own community.
  • Respect the growers’ knowledge of the land and recognize their capacity to be both savvy business operators and environmental stewards. Rather than prescribing a “one-size-fits-all” solution to growers, empower them with tools and information to make informed decisions on their ranches that benefit both the environment and their financial bottom line.
  • You can never anticipate all of the interrelated issues that affect resource use decisions on the farm. Food safety is a perfect example. Constantly evolving and building new relationships to address these seemingly external issues is critical to successful, collaborative conservation.
  • In addition to setting long-term goals, set some shorter-term ones and celebrate their accomplishment, both to recognize the stewardship efforts of growers and to maintain collaborative momentum among the partners.