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.

"Don't go into the water" is a warning Illinoisans may want to heed. A 2024 study released this week found all state-border beaches on Lake Michigan last year had evidence of contamination.

Findings from the Safe in Swimming report indicate these conditions could cause serious gastrointestinal and respiratory ailments. The data show bacteria levels were well above the EPA's "Beach Action Value" water quality standards. These guidelines help determine advisories and closures.

Emily Kowalski, outreach and engagement manager for the Environment Illinois Research and Education Center, explained the odds of exposure.

"One hundred percent of those beaches had potentially unsafe levels of fecal indicator bacteria at least one day in 2024, meaning that swimmers were potentially at risk," she said.

A water sample exceeding acceptable BAV standards increases the chances of a higher illness rate among swimmers. The study shows 71% of Great Lakes beaches had at least one potentially unsafe test day. Three beaches in Cook County had the highest degrees of dirty water - Winnetka Lloyd Park had the highest at 21. Glencoe Park and Montrose beaches had 14 days each.

The study identified runoff from paved streets and parking lots, and overflow from outdated, bacteria-encrusted sewage systems as harmful contributors. Livestock waste from concentrated animal feeding operations, or CAFOs, is another source.

Human contact with water tainted by manure could cause an E. coli infection. Kowalski suggested the environment could be one solution to interrupt the pathogen flow.

"Investing in nature-based solutions, green infrastructure, but also the repair needed in aging sewage systems nationally," she continued.

An estimated 57 million Americans experience nausea, diarrhea, ear and eye infections, and skin rashes after swimming in polluted waters. Kowalski adds the EPA estimates a price tag of $630 billion over 20 years will be needed to address sewage runoff and other wastewater problems nationwide.

Illinoisans can check the status of their favorite beach at Chicago Park District Beaches website.

Following last year's historic drought in Montana and hot temperatures early this spring, the Blackfoot River is running at roughly 25% of normal water levels.

Water rights have shifted some this year but experts said management will continue to be community-driven.

Clancy Jandreau, Blackfoot water steward for the nonprofit group Blackfoot Challenge, said the river's fish population declined in the late 1980s and early 90s, but there has also been a long history of restoration efforts. The new Blackfoot Drought Response Plan, updated in April, helps build on those efforts, Jandreau noted.

"We really wanted to more explicitly recognize that habitat restoration efforts that improve fisheries can in and of itself be a response to drought, as it builds resilient fisheries," Jandreau explained.

The new plan also incorporates deferred changes from the 2015 Montana Water Rights Compact, in which the Confederated Salish and Kootenai Tribes and Montana Fish, Wildlife and Parks became co-owners of a water right historically associated with hydropower production.

During a dry summer like this one, Jandreau pointed out the drought plan encourages a "shared sacrifice for shared benefit" model, in which irrigators, anglers and other water users voluntarily reduce their effects on the resource.

"Everybody's going to be seeking the refuge of the river over this summer," Jandreau added. "That includes humans and wildlife. So just doing their best to be aware of that and being responsible and ethical recreators this summer out there on the river."


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Because of drought and failing infrastructure, the state of Texas will run out of water by 2030, according to the Texas Water Development Board.

But two new pieces of legislation are on the books that are designed to address the state's water shortage.

Senate Bill 7 and House Joint Resolution 7 would allocate $20 billion for infrastructure improvements and new projects.

Agriculture Commissioner Sid Miller said he's been trying to get lawmakers to address the state's water crisis for 10 years.

"We completely lost our sugar cane industry because - no water," said Miller. "We've brought it to light that Mexico is not paying their water bill with our treaty on the Rio Grande, so that was brought to light. We've got a drought over half the state of Texas."

An increase in population has also contributed to the state's water woes.

JR 7 would authorize the state to use $1 billion a year from sales tax revenue for the water projects. The resolution must be approved by voters in November.

If the amendment is approved, the projects and funds will be overseen by the Texas Water Development Board. Miller said in the meantime, the state needs to do a better job at managing the water it has.

"We spend millions and millions of dollars on stormwater drainage, getting rid of excess water when it rains," said Miller. "We need to capture that water and use it. We need to capture the water out of these water treatment plants. I'm not advocating that we drink it but, my farmers sure would like to irrigate with it."

Miller said the state can also benefit from rainwater harvesting. He added that up to 70% of the state's water is lost, as it's transported to various municipalities because of old, worn-out infrastructure.




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