Algal bloom at Mantua Reservoir to be treated

The algal bloom that has plagued Mantua Reservoir every year since 2017 may be a thing of the past after a treatment to take place September 25, weather permitting, with possible follow-up treatments in the days following.

The treatment will be applied by BlueGreen Water Technologies, an Israeli company whose mission statement reads, in part, to “preserve and promote life on Earth by restoring, safeguarding and optimizing the health, safety of water bodies worldwide.” The company has successfully treated algal blooms in bodies of water both internationally and across the United States.

Mantua Reservoir is owned by nearby Brigham City and is a valuable water resource for roughly 20,000 people. Bear River Health Department issued a series of warnings this year about algal toxins in the water. The toxins can make humans and animals sick, and the department advised reservoir visitors to limit contact with water and to keep animals away.

“Brigham City has spent countless staff hours testing and monitoring algal blooms over the last several years,” said Tyler Pugsley, Brigham City Public Works Director. “These algal blooms have greatly affected recreational opportunities and limited our use of the reservoir.”

Granules will be spread over the reservoir by boat, plane, or both. The granules have a biodegradable coating that allows them to float across the lake before finally dissolving and releasing hydrogen peroxide into the water. The hydrogen peroxide creates an inhospitable environment for the algae, effectively causing it to self-destruct, and the remnants sink to the bottom of the reservoir and become part of the sediment.

Access to the reservoir will be restricted beginning September 25, including the boat ramp and beach. Only necessary personnel from Brigham City and BlueGreen Water Technologies will have access. Brigham City hopes to minimize closures and anticipates that treatment will take 1 to 3 days.

The treatment is safe for humans and animals and will not impact fish, waterfowl, or other aquatic life in the area or in any downstream usage or application.

“Our water quality is of the utmost importance to us,” said Pugsley. “Mantua Reservoir is a valuable water resource to our community, and we are excited for this partnership with BlueGreen Water Technologies along with the possibilities this treatment will provide.”

The project is being financed by environmental impact credits, at no cost to Brigham City. Because the dying algae sequesters carbon as it sinks, it is considered carbon capture technology. “While intensity and prevalence of toxic algae blooms continues to increase around the world, the cost of treatment is often a barrier to intervention,” said Jan Spin, BlueGreen President of the Americas. “By leveraging the potential of environmental impact credits, BlueGreen aims to make holistic algae bloom treatment highly accessible to government agencies around the world.”