Dredging slated for Grand Lake St. Marys

Blooms of blue-green algae overwhelmed Ohio’s Grand Lake St. Marys last summer.

Ohio plans to spend an additional $750,000 on dredging and sediment disposal in an attempt to clean up Grand Lake St. Marys. The amount adds to the $600,000 that the Ohio Department of  Natural Resources had already planned on spending this spring to remove phosphorous-laden sediment from the lake.

The new funds are part of a $7 billion state transportation budget approved by the U.S. Senate last week.

“This truly was a surprise for us,” said Laura Jones, an ODNR spokeswoman. “At this point, we’re looking at our plan and how we can most effectively use that money.”

Dredging was one of the improvement actions deemed a priority for the lake earlier this year by Ohio Gov. John Kasich and the directors of the ODNR, Ohio Environmental Protection Agency, and Ohio Department of Agriculture to improve the lake’s water quality.

“We welcome any additional assistance in addressing the water quality challenges facing Grand Lake St. Marys,” said ODNR Director David Mustine. “Governor Kasich recognizes how vital this popular recreational lake is to the local economy and appreciates the efforts of [State] Senator [Keith] Faber and many others who are pulling together to return the lake to a healthier state.”

The Ohio EPA also intends to invest $5 million this spring in the application of granular aluminum sulfate (alum) to the lake. The substance is used to bind with phosphorous in the water so algae can’t feed on it, thus rendering excess amounts of the nutrient inactive.

Additional methods being implemented include the installation of water treatment equipment and removal of fish species that are believed to stir up the bottom sediment in the lake, which releases more phosphorous into the water column.

Last year, many Ohio lakes and streams, Grand Lake St. Marys in particular, were plagued by cyanobacteria, forcing government officials to issue “no contact” and surface scum advisories throughout the region.

Following the advisories, an initial plan to clean the lake was released, which focused on both internal and external nutrient loading. The first round of treatment outlined by the plan focused on internal loading. Projects included a trial run for alum treatments and an attempt to physically flip the thick algal mats covering the water.

The state had already planned to remove 200,000 tons of sediment from areas in the lake that had been considered to contain the most phosphorus. According to Jones, it’s unclear how much more will be dredged using the new funding.

Dreading to begin at Grand Lake St. Marys [The Daily Advocate] State adds to funds to dredge algae-plagued lake [The Columbus Dispatch]