“Following ongoing monitoring of the lake, a small area of green algae has now developed into blue-green algae,” said Lakeside Boathouse, which manages activities on the lake. “Blue-green algae can be harmful, and everyone's safety remains our absolute priority. “Lakeside Boathouse remains open, and the following activities are still available: dragon boats, rowing boats, canoeing (and) rafting. “Following ongoing monitoring of the lake, a small area of green algae has now developed into blue-green algae,” said Lakeside Boathouse. That and the latest outbreak follows on from a disastrous 2025, when the lake suffered a damaging year, when a major outbreak of blue-green algae in July killed scores of fish – including the lake’s largest resident, a mirror carp weighing nearly 29 pounds.