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 lake levels for Okanagan Lake kokanee and downstream flow for 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 Nation Alliance and Canadian Okanagan Basin Technical Working Group (COBTWG) identified improvements to Okanagan River flow management practices as one means of achieving significant sockeye production gains. With this goal, the COBTWG oversaw the development of Okanagan Fish-Water Management Tool (FWMT), an Internet-accessible software application, as the central tool for defining these improved water management practices. The FWMT 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.
The location for In-Lake monitoring for FWMT is suwiw̓s (Osoyoos Lake). The Temperature and Dissolved Oxygen takes place at 2 sites on the lake over the course of the summer, monitoring the thermocline for the lake “Squeeze”. The Acoustic Trawl Surveys (ATS) are conducted from June to October nighttime only. These surveys are conducted to monitor growth and survival of juvenile Sockeye and Kokanee, determine if there is any competition for food between hatchery-reared juvenile Sockeye and resident Kokanee in Skaha Lake, and to determine if juvenile Sockeye in Osoyoos Lake are being affected by mysid shrimp and assess impacts of low oxygen and high temperatures.
The two key goals of this project are to:
- Confirm emergence of sockeye fry (in the field) as predicted by FWMT
- Prevent scouring by confirming 100% emergence prior to increase in flows for spring run-off
This project also provides temperature and dissolved oxygen anaylsis with the goals to:
- Monitor Temp and Dissolved Oxygen (DO) levels in Osoyoos Lake
- Monitoring for the Osoyoos lake “Squeeze”