Last week, I wrote Part 1 in my series on Lake Okabena. I asked whether Worthington is losing its greatest asset and whether the community is giving enough attention to the lake. The article received great feedback from readers. The response was unanimous and clear: The lake is one of our greatest assets and it needs more attention and investment from the community.
Given the response, I decided to expand the series into three posts to fully discuss solutions, particularly from feedback from readers.
First, lake quality is not a new problem. The challenges of a shallow prairie lake are not unique to Worthington. I’ve spent time on lakes all over the region and they all seem to get green in the summer (sometimes much worse than Okabena). It’s also not a modern problem—algae blooms were reported on the lake decades ago and lakes can go through cycles. Some challenges we have to live with, but we can learn from others.
Second, unfortunately, there’s no silver bullet. The long-term solutions are indeed long-term and could take decades to implement. In preparation for this series, I sat down with Dan Livdahl of the Okabena-Ocheda Watershed to learn about the many good things they are doing. We talked about everything from giant aerators to draining the lake and digging it out with mining equipment.
Defining the Problem
From the feedback I received, it’s clear that we are not proud of Lake Okabena, and a lot of that has to do with water quality.
Let’s face it, Lake Okabena is a shallow, mud bottom prairie lake—we will never have crystal clear waters. I’ve been in lakes and rivers and oceans around the world and, trust me, it actually gets a lot worse than our murky water. This is also getting better and, until the torrential rains this June, I noticed a lot of improvement. Praise goes to the Watershed team, which is working hard upstream, removing rough fish, and building retention ponds.
Algae—this issue may be the chief concern for citizens. The “green paint” algae blooms start as early as June now and inhibit us from using the lake, and even the parks surrounding the lake. The algae affects the most people. Boaters can’t use the lake, fisherman can’t use the lake, swimmers can’t use the lake. Have you walked around the lake during a bad bloom? The smell is horrific, rendering many of Worthington’s parks and bike trails unusable, not to mention being aesthetically displeasing.
Can we address the cause? The cause of the algae is runoff. Approximately 70% of the runoff comes from Whiskey Ditch and 30% from town. Improving runoff is a long-term strategy that changes agricultural practices and land use for filtering. We definitely need to invest in the watershed, but there is overnight cure.
Can we address the symptom—the algae blooms themselves? Hopefully. One can largely kill the algae by chemically treating the lake on a monthly basis. This, however, has undesirable effects on fish and the ecosystem. As a nod to our local biotech companies, if you can create an economic, large-scale, ecologically harmless solution to lake algae, cities across the world will be clamoring for your product.
I am attracted to an out-of-the-box solution: Algae skimming.
Algae floats on top of the water, so it’s possible to simply skim it off the top like skimming the fat off broth. Several cities and lakes are now employing algae skimmers. An algae skimmer is much like a floating lawn mower: As you drive, rollers filter the water and deposit algae in a bucket. If seeing is believing, watch this video:
I spoke with the Minnesota-based manufacturer of the Eco Harvester above. The Eco Harvester will remove approximately 1 acre of surface algae per hour and it’s a good size for our lake. At less than $50,000, it costs about the price of a small tractor the city might use for maintenance (they offered under $40,000 for an end-of-summer sale).
I look at the algae problem much like having a giant park—we just need to mow it occasionally to make it useful. And, the algae can potentially be used as fertilizer after harvesting.
In my view, it’s worth having a conversation about whether an algae skimmer is a good investment for Worthington. An algae skimmer would solve our chief complaint and make the lake instantly more usable during the summer months. When other lakes in the region suffer algae blooms, Worthington would be a refuge.
There is much more to discuss about the future of Lake Okabena and how it fits into a strategic vision for Worthington. Clearly, we need to actively pursue solutions to immediately improve the lake. In my next post, Part III, we will discuss dredging. It may even warrant a new series on setting a vision for merging downtown and Sailboard Beach into a destination for shopping and dining. For now, I suggest that an algae skimmer may be part of that answer.
My question for you: Do you agree that an algae skimmer is part of the solution and would it be an investment supported by the community?