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USDA's Bay Delta Initiative Enables Landowners to Remove Insecticides from California's Walker Creek

Posted by David Sanden, Natural Resources Conservation Service, California in Conservation
Mar 04, 2015
Special tours continue to be a part of Colusa Glenn Subwatershed Program’s educational outreach to growers to encourage the use of good conservation management practices. NRCS photo.
Special tours continue to be a part of Colusa Glenn Subwatershed Program’s educational outreach to growers to encourage the use of good conservation management practices. NRCS photo.

Water in California’s Walker Creek is now safer for residents, farmers and wildlife because of the hard work of conservationists, with funding made available through Bay Delta Initiative, (BDI), an effort of USDA’s Natural Resources Conservation Service, (NRCS).

The Bay Delta region, located in the Sacramento and San Joaquin watersheds of California, encompasses over 38 million acres and is one of the most important estuary systems in the nation. BDI helps clean and conserve water in this region as well as enhance wildlife habitat.

BDI helped a landowner coalition create a watershed management plan to prevent chlorpyrifos from entering the creek through agricultural runoff. A variety of crops are grown in the Walker Creek watershed, including almonds, walnuts, prunes, rice, grain, corn, and olives.  The primary use of chlorpyrifos in the drainage is on almond and walnut orchards.

Chlorpyrifos, an insecticide that is widely used in agriculture, is toxic to aquatic organisms, and exposure has been linked in humans to neurological effects, persistent developmental disorders, and autoimmune disorders.

Walker Creek is a small waterway in Glenn County, California, that is monitored by the Colusa Glenn Subwatershed Program, (CGSP), a landowner coalition, to determine compliance with water quality regulations. Between August 2007 and July 2009, testing revealed that water quality standards for chlorpyrifos were exceeded three times in Walker Creek. These findings triggered a regulatory requirement for landowners to develop a management plan to prevent the chlorpyrifos contamination.

To develop and implement the plan, CGSP secured technical and financial assistance from NRCS, which outlined some of the conservation activities, or practices, that farmers could use to reduce use and runoff of chlorpyrifos. For example, NRCS works with farmers to implement an integrated pest management system, which is a sustainable approach to manage pests using a combination of techniques and technologies that may include chemical, biological, cultural, habitat manipulation, and use of resistant plant varieties. Chemicals and methods of chemical application are selected in a manner that minimizes risks to people, natural resources and beneficial insects.

Since the landowner coalition put the plan to work, no chlorpyrifos exceedances have been detected.

“This program demonstrates the effectiveness of intensive outreach coupled with management practice implementation to protect water quality in watersheds with irrigated agriculture,” said Pamela Creedon, executive officer of the Central Valley Regional Water Quality Control Board, in a 2014 report announcing completion of the management plan to eliminate chlorpyrifos exceedances in Walker Creek.

BDI uses a focused approach, targeting funding to specific resource concerns. It was a good fit for Walker Creek, enabling CGSP to expand extensive educational outreach efforts to farmers, including numerous targeted workshops on conservation practices, field days, farm tours, newsletters, and announcements of cost-share opportunities.

“The success of Walker Creek is due to the incredible leadership of our partner, the CGSP,” said NRCS District Conservationist Rob Vlach. “Their outreach and education effort was fundamental to getting the word out about the Bay Delta Initiative. But the true measure of success is the fact that their water monitoring has shown zero exceedances since we implemented the program.”

Cover crops provide a number of benefits for soil health, wildlife habitat, and water runoff prevention. In this case, cover crops helped prevent the runoff of chlorphyrifos into local waterways. NRCS photo.
Cover crops provide a number of benefits for soil health, wildlife habitat, and water runoff prevention. In this case, cover crops helped prevent the runoff of chlorphyrifos into local waterways. NRCS photo.
Category/Topic: Conservation