Restoring an impaired waterway is possible. After two decades of work, the Iowa Department of Natural Resources has successfully rehabilitated Lower Gar Lake in the Iowa Great Lakes region.
While there's quite a bit of chemistry behind the recovery process, that's not really the most important part about conservation, said Ginger Walker, western basin coordinator for the DNR. Improving water quality doesn't have to do with any one particular policy or technical solution. It's about changing the culture.
"The nutrient reduction strategy that the state is using is really clear about the science of what needs to be done," Walker said. "It's just the scale of it that is daunting, because so many people have to participate in conservation at a level we've never seen."
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"Conservation is a people issue," Walker said. "I thought when I started my career that it was all going to be about science, but it's really all about people."
Dickinson County's Lower Gar Lake had excess phosphorus, a chemical element used by all living things, Walker said. It's often found in manure applied to fields to boost phosphorus levels for crops in Iowa.
Reports from the Iowa DNR identified concerns with phosphorous levels in the lake dating to at least 1990. A report in 1994 said the lake's phosphorus levels were among the highest of 116 tested between 1990 and 1992.
Walker said phosphorus enters Iowa's waterways much like nitrates do. Instead of dissolving into water, phosphorus clings to soil. When that soil washes into a waterway, it brings phosphorus along with it, where it can cause harmful algae blooms.
"If we had known then what we know now, maybe we would have been more careful with the erosion and the sediment that entered all of our water bodies," Walker said.
While the DNR is trying to prevent new phosphorus from entering Lower Gar Lake, much of the problem comes from legacy phosphorus left behind by decades of farming and development. In addition, there are still a lot of unknowns when it comes to the long-term effects of having phosphorus stuck in the soil.
"It's part of the reason why a watershed project takes a really long time to see results," Walker said.
KTIV reported that efforts stopped more than 6,900 tons of sediment from flowing into the lake and reduced phosphorus by more than 15,000 pounds a year.
It's not possible to chemically remove the phosphorus in a lake that size. Instead, the DNR focused primarily on educating landowners.
"What really has made a difference at the lakes is not so much the individual practices that we're using, it's more like the approach," Walker said.
Because Dickinson County relies on tourism to sustain its economy, the businesses there depend on the health of the lake to make money, Walker said, which is exceptional for Iowa.
Walker attributes a lot of Lower Gar's success to the presence of a local watershed coordinator who can oversee that specific project. A coordinator who educates residents, conducts outreach and introduces farmers to new practices can foster a shared sense of purpose in the community.
One measure of a watershed project's success is how many people follow up with conservation professionals about implementing new practices.
The educational component of such a project can include flyers, social media, classes or anything that gets people thinking about what conservation changes mean for them. A farmer could talk to their fertilizer salesperson and discover more about soil health and the retention of water on their land, for example.
"We have some really excellent farmers who are doing all the right things, and sometimes their next-door neighbor is just farming conventionally and not taking the risks that sometimes are associated with trying new things," Walker said.
The way to improve water quality mainly comes down to doing the right kind of outreach, Walker said. In the Lower Gar watershed, there has been so much environmental and water quality education for so long that it has fundamentally changed the culture.
"In the North Raccoon River watershed, for example, which is such a big concern for water users in Des Moines, that river, it's just there. It's always been receiving their wastewater," Walker said. "They are not looking at their economy as depending on the health of that river. They're not expecting to build big houses and bring big boats and hang out on the North Raccoon River."
Although more landowners in the North Raccoon watershed are making their own decisions, Walker said she's optimistic.
"The information is available, the funding is dedicated to it, there are watershed coordinators on the ground," Walker said. "I think all the pieces are in place. But it will just take time to change the culture of, 'How do we use the land?'"
The condition of Lower Gar Lake could very easily revert to its previous, impaired state if water protection strategies don't continue, Walker said.
"We're never going to arrive at a place where we fixed (water quality)," Walker said. "We're always going to have to keep working on this."
Lucia Cheng is a service and trending reporter at the Des Moines Register. Contact her at [email protected] or 515-284-8132.
This article originally appeared on Des Moines Register: Can a rehabilitated lake offer tips to address Iowa's nitrate issues?