The water at Butchers Dam near Alexandra remains out of bounds after last week’s discovery of potentially toxic levels of algal bloom, triggering an amber alert.

The Otago Regional Council (ORC) raised the alarm late last week and urged people to keep themselves and their dogs away from the water after samples showed the presence of cyanobacteria, also known as toxic algae.

The algae, officially called Anabaena Lemmermannii, can be deadly to humans and animals.

The ORC has continued to monitor the area and confirmed, yesterday, that it was still not ok for swimming or letting dogs near the water.

Signs have been put in place to warn visitors and locals about the dangers.

Weekly sampling will continue and the warning will stay in place until two successive results at the surveillance level, which is the green mode, have been recorded.

ORC scientist, water quality and programme lead Helen Trotter said, last week, given the staff observations, the previous history at the site and the continuous presence of cyanobacteria scums over the past week, it was decided the warning was needed.

This summer ORC will test 33 swimming sites weekly for bacteria and 11 sites for toxic algae.

The latest water quality results are then posted to Land Air Water Aotearoa’s website, a resource for New Zealanders across the country to check the quality of their favourite local waterway.

To find the latest toxic algae sightings visit the ORC website.