Kalavista Lagoon Water Quality and Contributing Factors Assessment

2018

$86,600

$4,390

The goal of this project is to provide a baseline assessment of water quality and factors that contribute to water quality within the Kalavista Lagoon. This data will serve as the basis of an adaptive management process for restoration to improve lagoon water quality, with a commitment to assessment, action, monitoring and plan improvement as necessary, as per the adaptive management framework. Factors which likely contribute to poor water quality of the Kalavista Lagoon are Common Carp and Canada Geese as explained. Therefore, baseline assessment of Common Carp and Canada Goose populations are also part of this proposed project. Factors related to improved water quality such as the presence of certain macro-invertebrate taxa and aquatic plants will also be monitored because of the ease and efficiency with which they provide valuable information about ecosystem function.

Our multi-year plan is to restore the Kalavista Lagoon as a community asset: a pleasant water feature with abundant wildlife where nature lovers and paddlers can recreate, and school science classes can learn about ecology. In order to restore the lagoon as a healthy and ecologically diverse pond community, the District of Coldstream has engaged a consulting firm to examine methods of improving water quality such as re-establishing water flow through the lagoon, enhancing riparian vegetation and excluding Common Carp. Common Carp are known to disturb sediments, increase turbidity and prevent growth of aquatic vegetation. Other proposed actions include controlling Canada Goose as a source of nutrients and E. coli in collaboration with the Okanagan Valley Goose Management Program (egg addling, barrier fencing and vegetation etc.). Sediment removal to deepen areas of the lagoon would halt the successional progression of lagoon infilling and help to maintain the wetland. Habitat enhancement for blue-listed Western Painted Turtles will include sand and gravel mounds for nesting and sunning logs in deeper water areas. Educational signage will be installed regarding pond ecology and the restoration process, along with the construction of viewing and dip-netting platforms for environmental education. The restoration of the Kalavista Lagoon will complement the proposed creation of a Nature Centre on a municipally owned property and building adjacent to the lagoon.

The presence and abundance of blue-listed Western Painted Turtles will also be monitored, not as part of this grant application, but as part of a Habitat Stewardship Program grant application. Western Painted Turtles often persist in poor quality water, but the Kalavista Lagoon turtle population has declined since the 1990’s, possibly due to infilling of the lagoon with sediment or a decline in available food due to the presence of Common Carp. The lagoon becomes very shallow in late summer and on occasion has been reduced to mud flats. 17 turtles were observed sunning simultaneously in the spring of 2017.

Although water quality samples have been taken from the lagoon ten years ago (2008), water was sampled on a single day and not over time. Water quality analysis has not occurred systematically at multiple sites 4 over the course of a season (February, May, July, September) as is required to provide sufficient data (statistical power) to overcome sampling variance and support the adaptive management process.