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For Immediate Release: 12/5/2014

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Water Hyacinth Mechanical Harvesting Begins in the Delta


Vicky Waters





SACRAMENTO, Calif. – The California State Parks Division of Boating and Waterways (DBW) will begin mechanical harvesting of Water Hyacinth in parts of the Delta this morning. A contract was finalized this week with Clean Lakes, Inc. of Martinez, and harvesting will take place in areas most impacted by the hyacinth.

The focus of the mechanical harvesting will begin with a section of the Stockton Deep Water Channel from Weber Point to Buckley Cove.  Other adjacent areas where water hyacinth has travelled and is impairing navigation will also be harvested.  Water hyacinth is an aquatic weed that is reactive to changing weather conditions.  While it thrives in warm and dry weather, it can move and travel within waterways in rainy and windy conditions, and die off in hard freezes.  Rain and wind can impact treatment, so harvesting will be conducted in infested areas if weather conditions are favorable.

DBW recognizes the challenges with water hyacinth, and its impact to the public. New treatment methods and chemicals are continually being considered. Mechanical harvesting is an alternative treatment for DBW that is in compliance with federal environmental regulations to deal with this invasive aquatic plant.

The Division of Boating and Waterways conducted its annual herbicide treatment season for Water Hyacinth in the Sacramento-San Joaquin Delta (Delta) since March 2014 through the end of November. As of November 26, 2014, the Water Hyacinth Control Program completed 561 herbicide treatments in 149 sites that cover the Delta, San Joaquin River and Tuolumne River. Approximately 2,500 acres of water hyacinth were treated with glyphosate and 2, 4-D. Continuous monitoring is conducted to ensure navigability of waterways.

DBW works with the U.S. Department of Agriculture to obtain approval for conducting the WHCP from the U.S. Fish and Wildlife Service and the National Marine Fisheries Service (part of the National Oceanic and Atmospheric Administration). A third approval is also obtained from the Central Valley Regional Water Quality Control Board.   The approval process is in place to determine if the use of these herbicides may affect any threatened, endangered or sensitive species, and critical habitats.

In 1982, California state legislation designated DBW as the lead state agency to cooperate with other state, local and federal agencies in controlling water hyacinth in the Delta, its tributaries and the Suisun Marsh. There is no known eradication method for water hyacinth once it has been established. Therefore, DBW conducts a control program as opposed to an eradication program. The program seeks to minimize negative impacts of the invasive plant on navigation, public safety, recreation, agricultural activities and ecosystem services in Delta waterways.

Funding for water hyacinth treatment comes from the Harbors and Watercraft Revolving Fund, which receives revenues from boaters’ registration fees and gasoline taxes.

In addition to mechanical harvesting, DBW crews will provide assistance with other removal methods, such as herding and hand-picking, in an effort to continue providing an essential public service.

DBW encourages the public to report water hyacinth sightings via the following 1-888-326-2822 or email DBW at  For more information on DBW’s Water Hyacinth Control Program, visit

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