Ohio EPA addressing river nutrients

Harmful algal bloom
Harmful algal bloom as seen from the research docks of The Ohio State University’s Stone Laboratory on Gibraltar Island in Lake Erie in 2013. Image by Jeff Reutter, courtesy of Stone Laboratory.

ASHLAND, Ohio — With the expectation that new water quality rules are coming to Ohio’s large rivers, the Ohio EPA is holding informational meetings to discuss the indicators of polluted rivers, and potential targets for nutrient loading.

Robert Miltner, a scientist with the EPA’s Division of Surface Water, held meetings April 6 and 11 to discuss “eutrophication,” the process that happens when a river or body of water becomes over-enriched with nutrients, leading to the excessive growth of plants and algae.

Miltner said a common indicator is the amount of green pigment in the water, or chlorophyll. When levels get much above 50 micrograms per liter, the growth causes wild swings in plant respiration and dissolved oxygen levels in the water, which can harm the fish and aquatic life.

Chlorophyll levels above 100 micrograms per liter are generally over-enriched, he said.

Taking action

Miltner said it’s relatively easy to determine which waters are impaired by over-growth, but the hard part is to determine what to do next.

“The first, obvious answer is we have to reduce the nutrients, but the next question is, how much?”

Miltner said he cannot predict what will become the state’s final standard, but what he’s seen in other parts of the country, and in literature, is a phosphorus target of 130 micrograms per liter.

He said the current EPA meetings are considered “early stakeholder outreach” in a process that will take several months to complete, and possibly several years. The goal is to come up with stakeholder-supported rules and standards that will govern water quality in Ohio’s large rivers.

“I think there’s a priority that’s there and a real interest in trying to get this moved forward,” he said, noting the process could be completed within a year.

The meeting April 6 included about a half-dozen participants, mostly local soil and water district representatives, and the executive for the Ohio Dairy Producers Association. Miltner said the meetings are public, and more stakeholders will be invited as the EPA considers a final standard, and implementation guidelines.

“Part of this is to generate interest, to start getting people aware of what we’re doing, but it’s also to start to get feedback,” he said.

Impaired waters

In March, the Ohio EPA released a draft report of the state’s latest list of impaired water bodies, which included the western basin of the open waters of Lake Erie. The state has battled water quality concerns over the past decade related to harmful algal blooms in the lake, and nutrient overloading in its rivers.

Miltner likened Ohio’s rivers to those in England, where he said there are similar stressors on the rivers, including a high population, and agricultural land use.

He said when a body of water is listed as impaired, it triggers an action from the EPA.

“If it’s listed as impaired, it forces us to take action and develop a plan to remediate that problem,” he said.

The goal, he said, is to form a standard for rivers “that achieves restoration” and “that is cost-effective and is not too onerous or burdensome on the regulated community.”


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