Efforts to keep geese away from the Millennium Park ponds in Castlegar are working, but algae blooms are still appearing, city council has been told.
Engineering manager Ryan Niddery presented an update to council this week on work by city staff to finally get to the bottom of the problem, which has persisted for several years.
“Goose counts have gone down substantially since early 2026, indicating our efforts to deter Canada geese from establishing in the park have been successful,” he said. “But we’re still seeing algae blooms.”
The city has reinstalled aerial flagging above the ponds to deter the geese and hired a dog handler team to further discourage them.
Councillor Brian Bogle said he can tell the difference. “I was down there several times in late June and early July and it is remarkable how few geese there are compared to last year,” he said.
The city has also increased flow to the ponds to improve turnover and reduce stagnant water, Niddery said.
Algae blooms occur given the right conditions, including sunlight, water temperature and nutrients. Specifically, nitogren, phosphorus, and ammonia contribute to algae growth, which is common in ponds and other slow-moving water bodies.
Water sampling is ongoing to better understand the nutrient levels in the ponds and what contributes to them, Niddery said. Once they have that information in hand, they will make recommendations to address the root cause of the algae.
“We will need a full season of information to assess trends and effectiveness of the changes,” he said. “A year-end review will inform whether existing measures should continue, be adjusted, or supplemented with additional improvements.”
Niddery said while geese feces are the most logical source of the nutrients, there are other possibilities, such as fertilizer from the sports fields.
Council set aside $10,000 in this year’s budget to support the anti-goose campaign as well as the water monitoring program. Niddery said they should not need to spend more than that.
The smallest and shallowest of the three ponds is not in use this year.
