Weiss: Making a plea to save local water quality
Across the state, especially in southern Minnesota, a lot of areas have seen greener lakes in recent years. Here's a plea to better the quality of local reservoir water.
I’ve been mulling more about water for several weeks after a disheartening visit earlier this month to the reservoir at Chester Woods Park east of Rochester.
I’ve also read more avidly about water-related disasters in the region, nationally and internationally. I’ve concluded water is trying to tell us something, even more now. It’s something like, "look at me, pay attention!"
I know, I know, this sounds like another “save the planet” plea.
I suppose it is.
But it’s also a save-the-water-locally plea, it’s one thing we can do something about.
My mulling began when my wife and I went to Chester Woods hoping to canoe the reservoir. We took one look and went home. Water in the launch area was thick with green gunky algae that spread well into the reservoir. I wasn’t totally surprised because the seven flood-control reservoirs around Rochester do get that way. But this time, I was upset, ticked off. Why is a great recreation resource looking so wretched?
I checked four other reservoirs — three were also much too green around the shore with algae, though one with a smaller watershed didn’t have much.
What was surprising was the attitudes of anglers, paddlers and others I talked to — most just shrugged it off, saying it’s been hot, it’s just the way it is. Only Evey Loftus of Plainview, who fished Chester Woods, seemed perturbed.
“It was very green all over,” she said. “In some spots it was worse than others … kind of gross,” though some parts looked good.
I was also upset — but not surprised — about news in late July of a kill of approximately 2,500 fish, mostly trout, in Rush Creek south of Lewiston. It was the third one within eight miles in the past several years. While others may have shrugged this off, trout anglers are upset and demanding the state enforce policies that protect trout streams and do more education.
For sure, that green gunk, which should disappear when it gets cooler, and the fish kill are nothing compared with the worldwide chaos of water — too much in Pakistan (a third of the country is under water) or the flooding in large parts of the United States with dozens dead, along with severe continuing drought in the American southwest and Europe. Those wider problems point out that we are not alone. But we don’t need a mega-flood or massive drought to heed water. We only need to look local.
'It shouldn't be bad for fish'
The green gunk in reservoirs “is just a cycle that these reservoirs go through … It doesn’t need high amounts of phosphorus, just the right condition, to create algal blooms,” said Brian Beyerl, a fisheries specialist with the Department of Natural Resources and the official who oversees the reservoirs. Reservoirs have too much phosphorus, which ran in from its watershed, and as the water gets warm in late summer, we get the algal blooms. “It shouldn’t be bad for fish,” he said, though blue-green algae can be toxic for pets.
In Minnesota, it’s illegal to spread phosphorus on lawns and it would be good for farmers to put less on their fields, “but that is kind of a hard sell,” he said.
Kristen Dieterman, a Minnesota Pollution Control Agency watershed project manager in this region, said some bodies of water are naturally clearer than others. Reservoirs like Rochester’s are meant to hold back water to dampen the chance of flooding, so they naturally capture more sediment and phosphorus binds to that soil, she said.
It’s not only the local reservoirs that are having problems. “Across the state, especially in southern Minnesota, a lot of areas have seen greener lakes in recent years,” she said. It takes only one pound of phosphorus to create 500 pounds of algae, she said.
“There’s always things that we can do,” she said, though she cautioned that because there is an internal recycling of nutrients, change would be slow.
“After a very long time things could clear up,” Dieterman said. “It’s definitely not going to be the time frame anyone wants to see.”
I monitor the Zumbro River west of Rochester for clarity for the MPCA and nitrates and other chemicals for Olmsted County. Despite some times with little rain for two weeks this summer, the water never cleared up much past two feet. About 15 years ago, I had several weeks in a row with water clarity way past three feet. The average transparency dropped from an average of 52.5 centimeters approximately 15 years ago to 38 centimeters now.
Nitrates in the middle of the past decade were spiking well beyond the 10-parts-per-million federal limit and even averaged past the limit for a whole summer. Levels have been dropping and last year, with little rain, were quite low. This year with more average rain, they have topped the federal limit five or six times and have come close several more times.
“We sometimes see nitrate bind in the soils with low flow and low runoff conditions, then flush through in following years,” wrote Caitlin Brady, the county’s water resources coordinator. She added that nitrates can harm human health, can be toxic to fish and contribute to the hypoxia zone in the Gulf of Mexico.
Nitrates are also considered an indicator that there are other harder-to-measure pollutants in the water.
But there is some hope for the Zumbro. The 1 Watershed, 1 Plan for the entire Zumbro River Watershed is complete and there is money, or soon will be money, to help slow the flow of potential flood waters as well as help keep soil and chemicals on the land. One of the plan’s top priorities is improving degraded surface water quality.
The fish kill on Rush Creek was a clear sign something went wrong. “Evidence indicates that this fish kill likely did not occur naturally,” according to the MPCA that is continuing to investigate. It has not been able to trace the problem back to a specific farm in past kills.
Prevention should be priority
Jeff Broberg, a geologist and fervent defender of trout streams, said there are many sinkholes in that area so it’s possible the problem was actually from land a few miles from Rush. It’s not critical to find out who did it this time but that the state enforce its rules, or do more education, about storage and spreading of manure and crop spraying before a chance of heavy rain (the kill happened right after a heavy rain).
“We ought to be doing risk management and preventing it in the first place,” he said. “We are making this the norm. That is the tragedy.”
Fish kills might not be able to be stopped completely, said Lauren Lewandowski, a MPCA communications specialist. Heavy rains are becoming more common in the karst region (little topsoil over porous rock) of southeastern Minnesota so even if everyone follows the rules “things can happen,” she said. She said they are trying to get out the word.
“We are working with landowners in the area to regulate and provide important information,” she said. “Our agencies have discovered that certain stream flows and weather conditions can produce increased risk.”
So that’s where we stand now. Like I said, water is telling us something,
Here are some things the MPCA suggests urban and rural people can do to help:
- Minimize fertilizers, herbicides and pesticides on lawns.
- Plant native grasses and flowers.
- Avoid applying manure or pesticides in sensitive areas and use the Department of Agriculture runoff risk-evaluation tool to minimize the applications.
- Never pour or sweep grass, leaves or anything else into storm drains.
- Use crop rotation, tillage and other methods to lower pest populations and use fewer pesticides.
- Use cover crops to keep soil and organic matter on the land and use buffers to trap pollutants.
John Weiss has written and reported about Outdoors topics for the Post Bulletin for more than 45 years. He is the author of the book "Backroads: The Best of the Best by Post-Bulletin Columnist John Weiss”