The Okanagan Fish-Water Management Tool: Balancing water objectives in real-time and promoting sockeye smolt production gains

Posted March 2006

 

By Clint Alexander, ESSA Technologies Ltd.

 

Water levels in Okanagan Lake are managed to provide a balance between fisheries, flooding, and other interests. Water levels must provide sufficient water to meet target flows for Okanagan Lake kokanee and downstream sockeye salmon populations. Owing to a variety of factors, Okanagan River sockeye are the only significant remnant stock of more than a dozen anadromous salmon stocks that historically returned to Canada through the U.S. portions of the Columbia River.

 

The Okanagan Basin Technical Working Group (OBTWG) identified improvements to Okanagan River flow management practices as one means of achieving significant sockeye production gains. With this goal, the OBTWG oversaw the development of Okanagan Fish-Water Management (OKFWM) an Internet-accessible software application, as the central tool for defining these improved water management practices. OKFWM enables water managers and fisheries scientists to combine best science subsystem models and integrate real‑time data to make daily/weekly decisions regarding Okanagan Lake Dam water releases.

 

Using this tool, a comprehensive retrospective analysis was performed for the 1974 to 2003 period. Results showed routine use of OKFWM may yield an average annual increase in Okanagan sockeye smolt abundance by as much as 55 percent, without significantly increasing socio-economic losses associated with other water use interests. This encouraging result owes to improved understanding of fundamental ecological processes controlling juvenile production, the application of real-time data to inform physical and biological parameters, and a heightened awareness of trade-offs—all features seamlessly captured within the OKFWM tool.

 

To access a PowerPoint presentation about the OKFWM tool, click on: OKFWM Presentation.