The Great Lakes hold about one-fifth of the Earth's fresh water, but a new report indicates they're getting saltier - and says that's reason for concern.

Lake Michigan used to sit at a salinity level of one to two milligrams of chloride per liter of lake water. Now, that concentration has risen to nearly 15 milligrams per liter.

Hilary Dugan, an assistant professor in the Center for Limnology at University of Wisconsin-Madison, said it's still a relatively low level for a water body as large as Lake Michigan. But rising chloride levels could pose problems for plants and animals in the smaller lakes and tributaries that feed into it.

"If anything, we're just hurting those native freshwater species that are adapted to, you know, Wisconsin waters that basically have no salt in them," said Dugan. "And now, you know, we've increased the salt ten-, hundredfold, depending on what body of water we're looking at."

She said salt levels have to hit roughly 250 milligrams per liter to pose a serious risk to plants, animals and humans, and notes virtually all the chloride pollution is from road salt.

Dugan added that people can reduce pollution in lakes and streams this winter by limiting their use of salt on roads, driveways and sidewalks.

Unlike other chemical pollutants, Dugan said salt pollution isn't irreversible. She explained that over the course of their life cycle, lakes and streams will gradually flush it out of their system.

"Salt stays dissolved in water, and so lakes and rivers will naturally flush themselves out," said Dugan. "So what it takes to reduce the salinity is just to stop the amount of salt that's going into these bodies of water."

The report found about 70% of the salt flowing into Lake Michigan comes from just five of the body's 300 tributaries.

Dugan said if nothing's done to address the issue, salt concentration in the lake will rise by about one milligram per liter, every two to three years.

As South Dakotans affected by recent record floods take stock of damages, researchers say water quality is among the concerns.

The state has been collecting damage data - but some impacts, like water contamination from livestock operations, are harder to quantify.

According to the nonprofit Food and Water Watch, coming into contact with or consuming manure-contaminated water can increase the risks of E. coli, giardia, and other waterborne illnesses. And those can lead to kidney failure, intestinal complications or cancer.

Amanda Starbuck, research director at Food and Water Watch, said public water systems are tested for these contaminants - but private, rural wells may not be.

"There's a lot of concerns about rural communities and their waters," said Starbuck, "and whether they have the ability, the financial resources, to test and to remediate any kind of contaminations that do stem from these factory farms."

Huge June rainstorms caused the Big Sioux River to swell up to 45 feet - breaking the previous record by seven feet, according to NASA, and inundating nearby farmlands.

Starbuck said South Dakota has some of the highest concentrations of confined beef, dairy and hog operations in the country.

Starbuck added that, according to a Food and Water Watch analysis, the state's factory farms produce nearly 22 billion pounds of manure each year.

"So, that's 17.5 times as much sewage as produced by the state's entire human population," said Starbuck. "So, we're talking about unsustainable amounts of livestock in these confinement operations."

She said the manure output should be of concern regardless of flooding. Still, river floodplains are expected to grow in coming years, according to a FEMA report.




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New York environmentalists want the Environmental Protection Agency to re-dredge the Hudson River. This comes after the agency released its latest five-year review saying more information is needed on the dredging efforts, although progress has been made. However, other reports show the EPA's dredging efforts failed, leaving the river riddled with PCBs.

Pete Lopez, executive director for science policy and advocacy with Scenic Hudson, said the EPA's reduction targets aren't being met.

"EPA has done its best to get massive amounts out of the river, but there are massive amounts left in the river, in our opinion, that are causing PCB levels to remain persistently high and dangerous. And, EPA is not addressing it. They're kicking the can down the road," he said.

Lopez thinks the agency should investigate where high levels of PCBs are and determine how to keep fish and humans safe from them. The EPA says more annual fish data can help discern whether the cleanup is meeting the expectations of the original plan. Once the data are available, the agency will issue an addendum to the current five-year report no later than the end of 2027. A public comment period on the five-year review is being held until October, with more information available at epa.gov/hudsonriverpcbs.

The river was dredged from 2009 to 2015 to remove 30 years' worth of chemicals General Electric dumped into it. Although the EPA warns against eating fish caught in the Hudson between Troy and Hudson Falls, people still eat them, which can lead to serious health impacts. Lopez said elected officials across party lines and different state regions want the EPA to take action in cleaning up the Hudson River.

"One would think that if 22 members of Congress, a U.S. senator and leaders of the Black and Puerto Rican caucus reached out, that you would step back and think about this, and maybe want to engage with them and talk with them."

Instead, he feels actions from the EPA have been "Pro-forma correspondence," sticking to the agency's assurance that the data aren't wrong.

Wyoming's irrigation infrastructure is aging and the state gets regular requests to update it but in some cases, project benefits may not outweigh the costs.

Parts of the Bighorn Basin are some of the driest in Wyoming, according to state data. The proposed Alkali Creek Reservoir Project would provide supplemental, late-season water to 33 irrigators across 13,000 acres of land, a design in the works since 2007.

Jason Mead, director of the Wyoming Water Development Office, said a recently announced potential design change, from an open irrigation ditch to a pipeline, added about $30 million to the dam's price tag. It also decreases the ratio of benefits to costs, a calculation the office does for any water storage project it works on.

"In regards to the grant and loan, we can grant up to 100% of a project per our criteria," Mead explained. "But it's not to exceed the public benefit."

Benefits include boating and fishing in the reservoir, the short-term benefits of dam construction and the indirect benefits to local and regional economies through increased crop production. Mead noted other considerations are the life expectancy of the dam, the ability and willingness of the users to pay for it and, of course, the direct benefit to irrigators themselves, who plan to use the water mainly for alfalfa, corn, sugar beets and barley. Opponents said the dam will disrupt natural watershed functions.

Dagny Signorelli, Wyoming director for the Western Watersheds Project, said the dam could reduce spring flows in Paint Rock Creek by 33%, in Medicine Lodge Creek by 16% and in Alkali Creek up to 100%.

"In general, dams disrupt natural river ecosystems by altering their flow patterns and reducing the frequency and intensity of natural flooding events," Signorell pointed out.

Signorelli added it could alter habitat for wildlife both upstream and downstream, with special concerns for trout, pronghorn, elk, mule deer and raptors. Plus, according to permit objections submitted by Western Watersheds Project in 2018, greater sage grouse use five breeding grounds within a four-mile radius of the project.


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