A call by Peachland council for a review of the current lake level management of Okanagan Lake has attracted the interest of the Okanagan Basin Water Board (OBWB).
At the board’s Friday (Sept. 4) meeting, the directors received a report from Anna Warwick-Sears, executive director of the OBWB, supporting the district’s argument.
In her report, Warwick-Sears said a review of lake level targets, current flow management models and climate forecast methodology was “a timely call to action.”
“Although the process of changing the plan for lake level operations is complicated, it is essential that the province review and update their operations plan within the next few years,” stated Warwick Sears.
With Shaun Reimer, the operator of the Okanagan Lake dam in Penticton, slated to speak to the board at their October meeting, Warwick-Sears recommended the board wait to hear from Reimer before making a formal response.
The issue initially arose at a Peachland council meeting last month when Coun. Terry Condon introduced a resolution, adopted by the council, to seek a review of lake management policy, which dates back to the 1970s, in response to consistent flooding issues that end up costing municipalities and private property owners thousands of dollars in property damage repairs.
“We can’t keep doing the same things and expect to see a different result,” said Condon at the meeting.
Council opted to not confront the issue head-on with the provincial ministry of the environment at this point, but solicit support first from the OBWB and Regional District of Central Okanagan board to send a stronger message.
In her report, Warwick-Sears noted during the preparing of Okanagan lakeshore flood maps, their consultants, Northwest Hydraulic Consultants, found the frequency of flooding would be extremely high if the Okanagan Dam at Penticton continued to be operated in the same manner, given the expected increase inflows due to climate change.
Working with the dam operator, the consultants helped to modify operational rules to be more protective against flooding.
“…If these modifications, or similar mitigations, are not implemented, the resulting flood flows and levels…are expected to be more severe than mapped,” said the Northwest Hydraulic report to the OBWB.
Warwick-Sears noted the operating rules changes done for the flood mapping project were only for the purpose of computer modelling.
“The old rules are still in place. In order to make changes to the rules, additional work will need to be done to evaluate the relative risk of drought and flooding under climate change and how to manage for both ends of the weather spectrum while minimizing harm,” said Warwick -Sears.
While the computer modelling dates back to studies done in the 1970s, the lake management policies based on those studies since have been complicated not only by climate change but also subsequent development on traditional floodplains around the lake and protection of the rehabilitated sockeye salmon run by the Okanagan Nation Alliance south of the dam.