Integrated Control of Invasive Aquatic Weeds for Preventing Blockage of Water Delivery Channels, Conserving Water, and Reducing Operating Costs
This Science and Technology (S&T) Progam research project is addressing integrated, cost-effective methods for controlling various highly invasive aquatic weeds in Reclamation water systems. Research questions include:
* What are the best integrated management options for controlling aquatic weeds that block these water delivery and irrigation systems?
* Can biological control methods (insects and fish) effectively be used for hydrilla, water hyacinth and other weeds in flowing systems?
* Can herbicides and biological control (insects) be effective ways to control giant salvinia in western irrigation and water delivery systems?
* Can grass carp be effectively used as alternatives to herbicides in environmentally sensitive, western delivery systems?
Need and Benefit
Reclamation has thousands of miles of canals and water systems at considerable risk to damage by invasive aquatic weeds which obstruct water flow, prevent access for maintenance and recreation, cause structural damage, and seriously threaten basin-wide operations. Major invasive aquatic plants which universally jeopardize Reclamation facilities include hydrilla, waterhyacinth, giant salvinia, Eurasian watermilfoil, and arundo. Control of these aquatic weeds will directly support all aspects of Reclamation's mission of enhancing western water supplies, increasing reliability, and saving money. Millions of acre-feet of water are lost annually to infestations.
Blockage of the Tracy Pumping Plant trash racks by water hyacinth can cause water revenue losses of one million dollars per day. Salvinia has invaded the Colorado River and threatens irrigation facilities. Recently, Rio Grande water managers were forced to waste an additional 30 percent of their water to push deliveries through 250 miles of hydrilla- and water hyacinth-infested portions of the river. There, hydrilla temporarily shut down water supply to Matamoros with nearly total blockage of the river. Hydrilla is presently in close proximity to the Colorado and Sacramento Rivers; where it threatens blockage to water supplies of tens of millions of people and millions of irrigated acres. New integrated management methods are needed including biological control (insects and grass carp). Grass carp provides savings of one million dollars annually for the CAP.
This topic supports the Reclamation contribution to research needs of two major, regional aquatic weed partnerships: Lower Colorado River Giant Salvinia Task Force (LCRGSTF) and Lower Rio Grande Binational Aquatic Weed Task Force (LRGBAWTF). Both groups share with Reclamation the above mission goals. Both are binational. Our participation is fully endorsed and partially funded by the respective Regional and Area Offices. While the LCRGSTF, by its title, has a primary focus on giant salvinia, there is also a broad, mutual interest in other aquatic invasives listed above. Giant salvinia research and technology deployment activities include development of herbicides and methods for biocontrol with United States Department of Agriculture (USDA), Animal and Plant Health Inspection Service (APHIS). The LRGBAWTF has interest in hydrilla and water hyacinth as well as other weeds listed. Our partnership activities include hydrilla biological control using triploid grass carp with Texas Parks and Wildlife Department, and hydrilla and water hyacinth biological control using insects with the Corps of Engineers. We are working jointly in herbicidal control technology transfer and with USDA/ARS in mapping and monitoring the spread of hydrilla. Products include Integrated Pest Management Plans, grass carp stocking plans, biological control demonstrations, survey reports, and numerous public and professional presentations. All results from this topic will have Reclamation-wide applicability.
Contact the Principal Investigator for information about these documents.