DBW Begins 2014 Egeria Densa Control Program in Delta

Vicky Waters
(916) 653-5115

Public Notice

June 04, 2014

Fluridone, in a form of a pellet, will be applied at very low rates. Treated areas will be monitored weekly to ensure herbicide levels do not exceed allowable limits, and that herbicide treatments have no adverse impacts on the environment, agriculture or public health in or near these planned treatment areas:

  • Bethel Island: Franks Tract
  • King Island: Bishop Cut and Honker Cut
  • Anchorages Boat Ramps and Marinas: Buckley Cove (River Point Marina and Ladd’s Marina), Cruiser Haven, Delta Yacht Club, Korth’s Pirate’s Lair, Oxbow Marina, Perry’s Yacht Harbor, BW Marina and Willow Berm Marina.
  • Clifton Court Area of Old River: Italian Slough and Kings Island
  • Sacramento Area : Sacramento Marina

All treatment areas will be treated once a week for 12 continuous weeks. Treatment is subject to change based on governmental requirements, weather conditions, plant growth, waterway traffic and other conditions. A public notice and treatment area maps may be viewed on DBW’s website.

Discovery Bay will not be treated this year, as the infestation levels of Egeria densa have been significantly reduced over the last three years of herbicide treatments by DBW.  Egeria densa is at a manageable controlled level in Discovery Bay and is not a hindrance to navigable waterways.  Given this current level, DBW is focusing herbicide treatment on other identified infestation areas within the Sacramento-San Joaquin Delta where navigable waterways are threatened. 

Sites were selected using both physical observation and underwater vegetation mapping techniques samples were also taken to determine the dominant species of underwater vegetation. Site selection was made based on the amount of vegetation found, recreational use of the area, propeller clearances and whether the vegetation was a hazard to navigation.

Egeria densa begins to show symptoms of herbicide treatment approximately three to four weeks after the first treatment. Bleaching of plant tips is one symptom. This bleaching continues down the stem of the plant eventually killing the plant.

The EDCP was established in 2001 to control Egeria densa in the Delta and its major tributaries. The program is managed by DBW with its federal partner, United States Department of Agriculture, Agricultural Research Service.

Egeria densa is a fast growing, non-native submerged aquatic plant having a significant impact on the shallow water habitat in the Sacramento-San Joaquin River Delta ecosystem. In the 50 years since the plant was introduced into the Delta, the infestation has grown to approximately 10,000 surface acres or 18 percent of 55,000 surface acres of the Delta. Egeria densa influences the Delta’s biological diversity, recreation and agriculture. This non-native invasive weed crowds out native plants, slows water flows, entraps sediments, obstructs waterways, impedes anadromous fish migration patterns and clogs agricultural and municipal water intakes. It is important to note that this plant has never been eradicated from moving water anywhere in the world.

For more information on the Egeria densa Control Program or to view reports, please visit www.dbw.parks.ca.gov/AquaticInvasiveSpecies.

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California State Parks Mission
To provide for the health, inspiration and education of the people of California by helping to preserve the state’s extraordinary biological diversity, protecting its most valued natural and cultural resources, and creating opportunities for high quality outdoor recreation.

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To provide safe and convenient public access to California’s waterways and leadership in promoting safe, enjoyable and environmentally sound recreational boating.