The upweller is an important piece of equipment for the nursery culture of several species of shellfish, such as the Eastern oyster and the hard shell clam. Upwellers powered by tidal action are used in regions where tidal flow can be captured effectively. In general, tidal upwellers have been designed based on trial and error, and built with materials the culturist has on hand. Extension associate Dana Morse initiated a project to bring engineering science into the understanding of how upwellers opearate, with the goal of improving their performance and efficiency, ultimately translating into higher profitability for shellfish growers. In a project funded by the Maine Aquaculture Innovation Center, Morse worked with Dr. John Riley, professor in the University of Maine (UMaine) Biosystems Science and Engineering Department, and members of the shellfish aquaculture industry in Maine. At the tow tank facility at the University of Maine in Orono, Dr. Riley determined the hydrodynamic theory that governs the performance of tidal upwellers and assessed the impacts of changes to some of the critical design components. Fieldwork performed at industry facilities helped to determine the flow rates through beds of shellfish of different size, bed depth, and species. An interim report was presented at the World Aquaculture Society (WAS) annual meeting last year and the final report was presented at both the WAS meeting in January 2002, and at the National Shellfisheries Association Meeting in Mystic, in mid-April 2002. An article on the project appeared in the November/ December 2000 issue of Fish Farming News. As a result of this study, project PIs have responded to inquiries received from Georgia, Washington, Florida, and Massachusetts and Canada on maximizing upweller performance.

Click here for the article "Oyster Options " from UMaine Today.

Click below for the report on "Optimization of Tidal Upweller Design"
PDF Version 1.24 MB 

For more information, contact Dana Morse.