HALIFAX -- The results of more in-depth water testing at Grand Lake, N.S. has ruled out the presence of petroleum products and hydrocarbons and has once again shown blue-green algae to be the issue.

Julie Towers, the deputy minister of environment and climate change, recommends residents who get their water from the lake continue to find an alternative water source for the foreseeable future.

"We recommend drilled wells that are properly constructed, dug wells that are properly constructed," explained Elizabeth Kennedy, an environment and climate change water quality specialist. "If municipal water is available or a public water supply is available and otherwise, an alternative water supply."

Now that blue-green algae has been detected in the lake, Kennedy says there is no way to get rid of it. She says a number of samples were taken at various locations around the lake and some did come back negative, however that doesn't mean there aren't toxins present.

"It just demonstrates that it’s about the concentration and the location that you're taking the sample in. That doesn't necessarily mean that there are no toxins present or there won't be toxins present where you choose to use the lake," said Kennedy. 

Towers says if people do choose to swim or boat on the lake, they are doing so at their own risk.

"Everyone is going to have to make their choices about what level of risk they are comfortable with," explained Kennedy.

No signs of contamination were found in nearby Fish Lake. Officials say there is a high probability of more algae blooms throughout the summer.

Anyone who sees an algae bloom on any lake in the province should contact their regional office of the Department of Environment and Climate Change.