Harpoon Brewery pale ale uses water from the Charles River

Charles River Boston water sunset — Swimmable for at least two years now.

Being from Cleveland, we here at CBB understand the challenges of keeping a river clean. We sympathize with Boston’s Charles River, which has also had its challenges. It just became swimmable again in 2013 (after $500 million and nearly two decades of work). In 2015, it’s good enough to drink — well, at least in a craft beer — and after the water’s been thoroughly vetted via an innovative water treatment system.

Boston-based craft brewer Harpoon Brewery and Desalitech, an water treatment company based in Newton, recenlty announced a new collaboration to treat and brew water from the Charles River to create a limited edition beer — Charles River Pale Ale.

Charles River Pale Ale will be showcased as a part of HUBWeek, a week-long celebration of creativity and innovation in October hosted by MIT, Harvard University, The Boston Globe and Massachusetts General Hospital. The beer will be available at select HUBWeek events and the public will have opportunities to sample the beer at the Harpoon Beer Hall in the Seaport.

“Harpoon is proud to call Boston our home and to do our part to build a stronger, more sustainable environment and community. As a long time tenant of the Seaport, we have seen both Boston Harbor and the Charles River transformed from their dirty water past to one of the city’s best natural resources as a result of the hard work of many passionate people,” said Harpoon Brewery President Charlie Storey. “We’re excited to partner with Desalitech to showcase the creativity and innovation of Boston’s leading companies, and to brew the limited edition Charles River Pale Ale.”

Pictured here is an example of one of Desalitech’s high-efficiency water treatment systems that purifies water through a high-recovery reverse osmosis process. Desalitech’s system recovered and purified 93 percent of the Charles River water to the degree that exceeds traditional tap water, making it ideal as ingredient water for beer.

The effort to create the beer began last week, when Desalitech participated in a one-time limited withdrawal of water from the Charles River and treated it through one of its industry-leading units that employs a treatment process known as reverse osmosis. Desalitech was able to recover 93 percent of the Charles River water, a significantly higher percentage than the industry average, while using less energy than traditional reverse osmosis systems — a hallmark of Desalitech’s innovative solutions. The result was potable, clean drinking water that was delivered to Harpoon Brewery last week. Harpoon Brewery will now initiate the brewing process and craft the final product over the coming weeks.

Storey said the Charles River Pale Ale is a light-bodied, copper-colored ale with a slightly spicy, fruity hop aroma. The malt profile and hop bitterness up front leads in to a sweet, smooth, hoppy finish. The alcohol by volume is 5.2 percent.

“Water scarcity is a global challenge that affects millions across the world — we are proud to be a Massachusetts company that is providing solutions and making an impact here in the U.S. and beyond,” said Nadav Efraty, CEO of Desalitech. “We are thrilled to join with Harpoon Brewery to demonstrate the efficiency and high rate of recovery we can achieve when treating water from all types of sources, including the Charles River.”