MINNEAPOLIS (WCCO) – A beer is usually not much more than a refreshing drink. But if you have a taste for light summer shandy, the next cold one could do much more than quench your thirst.

Tonka Beer Company is selling a unique beer that could help save the state’s lakes and rivers from invasive species.

There are certain ways to attract a crowd, free beer happens to be one of them. And at the Spirit of the Lakes Festival, visitors got an introduction to Big Island Shandy.

“Very good, light summer shandy. Very good,” said Scott Ramacier, a beer drinker from Mound.

Big Island Shandy is brewed by Chad Mayes, Ryan Johnson and Jason Landstrom, who all became proprietors of a longtime passion for microbrews.

“Over a period of time we came up with the idea of founding a beer company,” Mayes said.

The Tonka Beer Company became a reality about a year ago. It features one product, the shandy; but business is booming.

The taste is what brings in new customers.

“I think it’s great. I don’t typically love beer, because it’s so carbonated, and this is not that carbonated,” said JJ Ries, after trying the Big Island Shandy for the first time.

But those who taste the shandy like more than just its taste; a cause keeps them coming back for more.

“It’s a win-win. We get a drink and also saving for good cause,” Ries said.

All of Tonka Beer’s proceeds go to help fight invasive species in Minnesota lakes and rivers.

“We’ve just seen the rapid change in the lakes with the invasive species and we thought it would be good cause to fund,” Mayes said.

Businesses around Lake Minnetonka quickly jumped on board with the shandy’s cause.

“You almost have to have it, if you’re a spot on the lake,” Mayes said.

A cold one, on a hot day, rarely feels so good.

“We are saving the lakes one at a time. Only 10,000 to go,” Ries said.

The company is releasing a new IPA (Indian Pale Ale) at the end of August.

Big Island Shandy has been on the market since May, and so far, Tonka Beer has contributed $10,000 towards fighting invasive species.