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Regulators, environmentalists and scientists split on how to keep Missouri's lakes clean

A view of Lake Taneycomo in February 2018.
Eli Chen | St. Louis Public Radio
Lake Taneycomo in Branson is one of many lakes that the Environmental Protection Agency would consider "impaired," or polluted under its proposal to regulate nutrient pollution in Missouri. It would not be considered impaired under the state's proposal.

On a bright, brisk winter day in Branson, Mo., several dedicated fishermen tried to catch trout in Lake Taneycomo, a fast-moving, ribbon-shaped lake that snakes around the city.

The water appeared clear, but the lake has some ongoing issues, said David Casaletto, executive director of Ozarks Water Watch, a water quality group. For example, heavy rains in the summer have caused low levels of dissolved oxygen, which has hurt the trout population.

Under a recently proposed water quality rule from the Environmental Protection Agency, Lake Taneycomo, Mark Twain Lake and Lake of the Ozarks are among 113 lakes and reservoirs in Missouri that would be defined as “impaired” or too polluted for human use.

But the three lakes would not be considered polluted under the state’s proposal, which would list 34 lakes. Federal and state regulators disagree on how pollution from runoff should be addressed, and environmentalists are also divided on what approach should be taken.

Bodies of water that are labeled impaired would require a cleanup plan that would likely involve putting stricter controls on nearby wastewater treatment plants. Lake Taneycomo needs some improvement, but the water quality is not so severe that it needs a cleanup plan, said Casaletto.

“Why would you call this [lake] impaired? People are fishing here today while we’re out here,” Casaletto said. “It’s a viable fishery for trout.”

The Missouri Department of Natural Resources and the EPA are working on regulations to address nutrient pollution in lakes and reservoirs that are larger than 10 acres, such as Lake Taneycomo. Nutrient pollution occurs when pesticide and fertilizer runoff from agriculture or discharges from wastewater treatment facilities overload bodies of water with nitrogen and phosphorus. While the nutrients are an essential part of aquatic life, excessive amounts can render waters unsuitable for drinking or recreation, and cause fish kills, algal blooms and dead zones.

Ozarks Water Watch executive director David Casaletto standing near Lake Taneycomo in Branson in February 2018.
Credit Eli Chen | St. Louis Public Radio
David Casaletto, executive director of water quality group Ozarks Water Watch, supports MDNR's plan for regulating nutrients in Missouri's lakes.

Missouri has long attempted to develop a rule to prevent the consequences of nutrient pollution. The state submitted a plan to the EPA in 2009, which was ultimately rejected two years later. In 2016, the Missouri Coalition for the Environment used the Clean Water Act to sue the EPA for failing to make the state regulate nutrient pollution. That led to a settlement that required the federal agency to come up with a plan by mid-December 2017, unless the state could draft one first. The state had drafted a proposal, but missed the deadline to submit it.

Two maps show the difference in the number of lakes that the state of Missouri and federal regulators would consider impaired.
Credit Missouri Department of Natural Resources
The Missouri Department of Natural Resource's proposal would designate 34 lakes and reservoirs as impaired. The Environmental Protection Agency's proposal would make 113 lakes and reservoirs impaired.

The EPA will close the public comment period on two proposals this Monday, which are its own and the MDNR’s. Both plans monitor nitrogen and phosphorus, but the state’s plan sets higher thresholds for the nutrients than the EPA’s. The differences in nutrient limits results in different levels of protection, said Peter Goode, a scientist at the Washington University Environmental Law Clinic.

“The state’s proposal only proposes to protect aquatic life,” said Goode, who is working with the Missouri Coalition for the Environment. “The EPA’s proposal proposes to protect aquatic life, recreational uses and drinking water.”

“The rule that DNR came up is not in any way going to prevent water quality from getting worse. It’s just going to identify it when it’s gotten bad,” Goode added.

The state initially considered protecting lakes for recreational and drinking water use, but decided after stakeholder meetings to only set standards for aquatic life, said John Hoke, chief of the watershed protection section at the MDNR.

“In two-thirds of the state, the aquatic life use actually does protect what we project to be a protective drinking water supply use,” Hoke said.

Former EPA scientist Robert Angelo criticized the state’s proposal last fall when the MDNR was collecting public feedback for its plan. EPA Region 7 officials were concerned that the state’s proposal would be too reactive to fish kills, algal blooms and other consequences of nutrient pollution, said John Delashmit, the former chief of the water quality management branch for the region.

“The Clean Water Act is supposed to be protective,” Delashmit said. “You don’t want to be reacting to fish kills. It’s better that the fish stay alive.”

A couple of fishermen try to catch trout in Lake Taneycomo in February 2018.
Credit Eli Chen | St. Louis Public Radio
A couple of fishermen try to catch trout in Lake Taneycomo.

Other scientists argued that the EPA uses a one-size-fits-all approach that doesn’t consider the vast differences between Missouri’s lakes.

“You might have two water bodies that have the same nutrient levels, and one may be impaired in terms of aquatic life and the other may not,” said Daniel Obrecht, a lake researcher at the University of Missouri-Columbia. “One that may be impaired may be a 10-acre reservoir. The other that may not be impaired could be a 1,000-acre reservoir.”

Obrecht said the state does not have the resources to address pollution for the number of lakes that the EPA would consider impaired. Casaletto and others are also concerned that the EPA’s plan could impose higher costs on wastewater facilities connected to impaired lakes and raise sewer bills. The MDNR estimates its plan could cost $83 million to treatment plants, while the EPA’s plan could cost $1.7 billion.

“We need to protect [Lake Taneycomo],” Casaletto said, "but do we need to tighten down controls on treatment plants? It’s hard to say that it’s necessary.”

“The public looks at [lakes] and says, hey, 'Can I boat in this lake?,' 'Can I swim in this lake?,' 'Can I fish in this lake?', and if the answer is yes, then why would an agency say that this lake is impaired?” Casaletto added.

A view of Lake Taneycomo in February 2018.
Credit Eli Chen | St. Louis Public Radio
Lake Taneycomo has ongoing issues of heavy summer rains causing low dissolved oxygen levels, which has hurt its fish population.

While wastewater treatment plants would be held accountable, neither plan would do much to limit nutrients coming from agricultural runoff. It’s difficult to trace excessive nutrients to farms that may be causing the problem without extensive studies. The only system in place to address this are USDA programs that incentivize farmers to use technologies, such as cover crops, to reduce runoff.

The Missouri Coalition for the Environment contends that neither the state nor the EPA’s plan would be aggressive enough at preventing nutrient pollution.

“We think that the EPA should more or less go back to the drawing board,” Goode said.

Follow Eli on Twitter: @StoriesByEli

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