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EPA's plan to clean up Missouri's lakes may not be strong enough to prevent pollution

An aerial view of Lake of the Ozarks.
Courtesy Lake of the Ozarks Convention & Visitor Bureau
The Environmental Protection Agency has put forth its own proposal to clean up Missouri's largest lakes but environmentalists say it's just as weak as the state's plan.

The Environmental Protection Agency has released its proposal for tackling polluted runoff in Missouri's largest lakes.

But environmentalists say the EPA's plan, like the state's plan that was released in October, is not strong enough to address pollution. 

Missouri does not set limits for nitrogen and phosphorus, nutrients that can cause fish kills and create dead zones in excessive quantities. A Clean Water Act settlement last year with the Missouri Coalition for the Environment required the EPA to devise a rule to regulate nutrient pollution in Missouri's lakes by Dec. 15, unless the Missouri Department of Natural Resources filed its own proposal by that date. The state failed to submit a plan by the deadline. 

The EPA posted two potential plans online this week, one that it would advocate for and the other that mirrors the state's proposal. Both plans monitor levels of nitrogen, phosphorus and chlorophyll, a substance that's produced when there's a high amount of nutrients. When any of them surpass a particular threshold, then regulators will measure dissolved oxygen levels, fish kills and other consequences of nutrient pollution.

"It's unclear at this point whether or not [the EPA's plan] would be more protective or not," said Peter Goode, an environmental scientist at Washington University's Interdisciplinary Environmental Law Clinic. 

For example, Goode said, under the EPA's proposal the threshold for nitrogen and phosphorus is higher than the state's in the Ozark region, but the EPA's threshold for chlorophyll is lower in the same region. The federal plan aims to protect aquatic life, recreational use and drinking water, while the state's plan only aims to protect aquatic life. However, Goode pointed out that the EPA plan doesn't adequately describe how it will achieve that through numeric limits.

"They both take approaches that seem to focus on whether or not there is an actual water quality problem that exists," he said. "Neither one of them really take an approach that says we're trying to prevent water from getting bad." 

Overabundant nutrients are often caused by sewage discharges, and pesticides and fertilizer that run off of farm fields and urban stormwater.  About a quarter of Missouri's lakes that are at least 10 acres are impaired. 

Missouri DNR officials prefer their approach, as it considers a "larger set of Missouri lake data and peer-reviewed literature to establish its criteria," said John Hoke, chief of the department's watershed protection section. He considered the EPA's plan to be "more restrictive" and "would lead to issues of attainment in many of our state's lakes without associated environmental benefits." 

The EPA plans to take public comments on the two proposals on Feb. 7 and 8. The Missouri Clean Water Commission will also be meeting on Jan. 4 to vote on adopting the state's plan. 

Follow Eli on Twitter: @StoriesByEli

Eli is the science and environment reporter at St. Louis Public Radio.