photo by: Josie Heimsoth/Journal-World

Dozens of people gathered for a talk about how climate change affects the Kansas River on Thursday, April 3, 2025.

A river’s health has big downstream effects on the people and places that rely on it — and in Kansas and around the world, many rivers are getting sicker every day.

They’re carved up by dams and swollen and shrunken by climate change, and the ecosystems they support are in the middle of a biodiversity crisis. And all of this has implications for the quality of the water in these rivers — and the safety of people and property along them.

That was the message from a group of environmental advocates at a gathering Thursday evening at Sunflower Outdoor and Bike Shop, where dozens of people showed up to hear about the effects of climate change and other human activities on these ecosystems.

Sam Zipper, an assistant scientist at the Kansas Geological Survey, said at Thursday’s gathering that the state of water in Kansas is largely influenced by the climate, and that there’s a trend of more precipitation happening in eastern Kansas, along with an increase in extremely wet weather events, which includes severe or prolonged periods of heavy rainfall.

Spring is “typically the wettest time of the year, and so the wettest times are getting wetter,” Zipper said.

Friends of the Kaw, which organized the event, makes it clear in its policy statements that flooding causes much more harm than just damage to property. Because rivers are complex systems, they respond to changes in unpredictable ways.

The nonprofit, which is devoted to protecting the river ecosystem, has multiple policy statements about the river — among other things, it advocates against dredging in the river’s channel and for protecting the quality of the river’s water and working with communities to guarantee access to the river for all residents. And its statement on climate change says the river is in crisis.

“Climate change continues to significantly and negatively impact the Kansas River and has created a crisis for the river, the broader ecosystem, and river users,” the Friends of the Kaw policy statement says. “… Changes to patterns of floods and droughts not only impact the timing and delivery of water quantity to the Kansas River, but will also alter water quality through changes in sediment and nutrients.”

photo by: Josie Heimsoth/Journal-World

Dawn Buehler, Kansas Riverkeeper and executive director of Friends of the Kaw, speaks at a talk on how climate change affects the Kansas River on Thursday, April 3, 2025.

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Heidi Mehl, director of water and agriculture programs in Kansas at the Nature Conservancy, said Thursday that one way you can see the harm to rivers is in the loss of biodiversity.

The world is losing biodiversity globally at an alarming rate, and freshwater biodiversity has seen a significant decline, she said.

“We have a crisis on our hands,” Mehl said. “… We’ve lost an estimated 83% of our freshwater biodiversity (since the 1970s), and there are so many reasons for this.”

One big reason is the very measures humans take to protect themselves against flooding — dams and the fragmentation of freshwater systems they cause.

Dams disrupt the natural flow and connectivity of rivers, streams and other freshwater bodies. The system gets “broken up” into disconnected sections, which can impact the health of the entire ecosystem.

“(Species) just cannot find the habitat they need,” Mehl said. “They can’t find other members of their species.

“Globally, only one third of the world’s 242 longest rivers remain free-flowing,” Mehl said. But even the free-flowing rivers are under threat, as there are more dam proposals in places like South America and Africa for hydropower.

When measuring a river’s health, you have to take many things into account, including the form of the channel and the organisms in the river. But one thing that’s especially important is the natural flow regime, which refers to the typical patterns and variability of water flow that occur in a river system without human interference.

“A lot of our dams are explicitly for flood control, so they’re designed to knock these natural floods off,” Mehl said.

Mehl works in the Sustainable Rivers Program – a collaborative effort between The Nature Conservancy and U.S. Army Corps of Engineers, the largest water manager in the country – to find more sustainable ways to manage river infrastructure for both people and nature.

photo by: Josie Heimsoth/Journal-World

Heidi Mehl, director of Water and Agriculture programs in Kansas at The Nature Conservancy, is pictured on Thursday, April 3, 2025.

According to its website, the program has grown from eight rivers since it was first launched in 2002 to 44 rivers in 2022, influencing 12,079 miles of United States waterways and including 90 reservoirs and dams.

Some of the program’s initiatives have indeed helped reverse the negative impacts on wildlife in the nation’s rivers. The program worked with the Mel Price Dam gates on the Mississippi River, where dam managers were able to adjust outflows and mimic the ideal velocities for the spawning of lake sturgeon – a species that has declined significantly due to overfishing, dams, pollution and habitat degradation.

Following the effort, lake sturgeon spawned in spring 2022 below the dam, which was the first ever documented spawn in Missouri after 30 years of releasing the fish into the river to help restore the population.

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But dams and other structures that break up ecosystems are just one part of the picture. Another is how changes in precipitation and temperature are reshaping the environment, and Zipper described how dramatic they are.

“We’ve seen this kind of marching upwards trend where wet extremes are getting more and more common,” Zipper said. “They’re becoming a more dominant type of climatic extreme, and dry extremes are getting less common.”

He added that temperatures are also increasing. Zipper said nighttime temperatures are rising, and there are fewer cool nights, which can be ecologically stressful for species that rely on cool conditions to recover in the summer months.

“This increasing precipitation trend doesn’t necessarily mean the region is getting wetter as a whole, because that increase in temperature increases the water demands of plants,” Zipper said. “And as a result, it could mean that the area is overall getting more arid, despite the fact that we’re getting more rain.”

Eastern and western Kansas are almost divided in half, with each side having distinct sources of water. The east side has a more abundant supply of surface water, coming from rivers, streams and reservoirs. The area also benefits from a higher amount of precipitation, and it can help recharge the groundwater and availability of surface water.

photo by: Josie Heimsoth/Journal-World

Sam Zipper, assistant scientist at the Kansas Geological Survey, is pictured on Thursday, April 3, 2025.

In contrast, western Kansas, is much drier and relies heavily on groundwater sources. The region is part of the High Plains Aquifer system, which includes the Ogallala Aquifer, one of the largest sources of groundwater in the United States. Farmers in western Kansas rely on irrigation from this aquifer for crop production, especially in areas where rainfall is scarce.

Zipper said that in order to make change over a large area, it’s better to have many kinds of small conservation programs opposed to a handful of larger ones. Sheridan County established a Local Enhanced Management Area plan, or LEMA, to address heavy water use in the county that results from irrigation pumping. These are tools that help encourage farmers to pump less water, and the LEMA had farmers cut irrigation by 20%. The county ended up decreasing its water use by 31% in 2021, and now it has voluntarily cut irrigation by 40%.

If measures aren’t taken to change course, Zipper said the disruptions will spread. Local climate data has shown that the drier conditions typically found in western Kansas are now shifting eastward, he said. What once only reached Dodge City in the 1800s now extends as far east as Hutchinson.

“In the future, those dry conditions are projected to move further to the Kansas River Basin,” Zipper said.