This summer, a harmful algae bloom on Canandaigua Lake for the first time led to toxins in a drinking water supply from the lake. On Tuesday, experts with state agencies addressed concerns at a forum in Canandaigua.

But questions remain about drinking water safety in the light of recurring toxic blooms.

“It’s important we keep looking harder and harder to address these issues of algae blooms and everything that goes with it,” said Gorham Town Supervisor Fred Lightfoote, co-chairman of the Canandaigua Lake Watershed Counci.Toxins were found in the water supply from the Rushville plant, which lies in the Gorham water district and serves hundreds of people in Rushville and Middlesex, including buildings in the Marcus Whitman School District.

“It’s a dire concern. We’ve all got a stake in the game,” said Lightfoote, who led off a recent forum at the Canandaigua Middle School, co-sponsored by the council and Canandaigua Lake Watershed Association.

“It’s a very scary thing,” said Neil Atkins, president of the association, a nonprofit that works with the council of municipal leaders for the health of the watershed. “We know what happened in Rushville.” (Editor’s note: Toxins in the drinking water supply resulted in a brief drinking water ban in the Rushville district.)

A panel of two scientists with the state Department of Environmental Conservation and the director of the drinking water program for the state Department of Health discussed the algae problem and what is being done.

A combination of factors is fueling algae, a growing problem globally. Those include climate change, which is causing more severe storms and a gradual warming of lakes, along with pollutants. The number of waterbodies with harmful algae blooms statewide jumped nearly 600 percent over the past six years, from 58 in 2012 to 394 in 2018. Rebecca Gorney, research scientist with the DEC’s lake monitoring and assessment, said statewide there are 50 to 70 new water bodies added each year to the list for those with harmful algal blooms, or HABs.

Gorney and the other panelists talked about increased monitoring and efforts to help prevent blooms, as well as more quickly and accurately pinpointing HABs and protecting drinking water.

“There is not one silver bullet, not one quick cure, but we are working on it,” Gorney said.

Anthony Prestigiacomo, DEC research scientist with the Finger Lakes Watershed Hub, talked about research into why lakes with low phosphorus levels, such as Canandaigua, are plagued by HABs.Too much phosphorus fuels HABs. But as with other water bodies,Canandaigua Lake is affected by climate change that has brought more intense rainstorms and an uptick in water temperature hospitable to HABs. This summer, the average lake temperature was the warmest on record.