Saving the shoreline

• On Ocheda's banks

Paul Langseth stands on the bank of Lake Ocheda, which he hopes to protect from further erosion.

Talk about it

WORTHINGTON — Over the past 50 years, Paul Langseth has seen the banks of his family’s Lake Ocheda waterfront property slowly erode away because of large whitecaps slamming into the eastern shore on windy days and heavy rains washing away the shoreline.

It has taken years for the problem to get as bad as it is today — a 1,500-foot stretch of Langseth’s shoreline is now a cliff that rises 15 to 20 feet above the lake. Just as it took years for the shoreline to get to this condition, Langseth said it will take years to reverse it.

During a recent meeting of the Okabena-Ocheda Watershed District (OOWD), Langseth spoke of the issues along his shoreline, and his plans to seek funds to address them.

A member of the Nobles County Soil and Water Conservation District (SWCD) board, Langseth said he hopes to obtain a grant from Minnesota’s new Clean Water Legacy Act, which receives its funds from a three-eighths of 1 percent state tax voters approved a year ago. The legacy dollars, along with federal EQIP (Environmental Quality Incentive Program) funds, would provide cost-share funding in combination with landowner contributions and local partnerships. The OOWD has been asked to contribute funds for the work.

Langseth has received a $170,000 estimate for a lakeshore protection project that would include the installation of an 8-foot-high breakwater to reduce wave action and its impact to the shoreline. The project would also include the installation of a geotextile fabric and the addition of riprap and fieldstones along the cliff for stabilization and prevention of further erosion.

“I’ve never worked on a project as big as this, so I’m excited to see it,” said Stephanie McLain, NRCS District Conservationist in Worthington. “It would be an awesome example of how we can go along and repair (shoreline erosion).”

Langseth said there is no economic benefit for his family to spend the $170,000 for shoreline stabilization, however there would be a benefit to the watershed.

Murky waters

Over the years, the soil that has eroded along Lake Ocheda’s shoreline has ended up at the bottom of the lake. The sand and silt has made the prairie lake shallower, but more importantly, has led to water clarity and water quality problems.

Lake Ocheda, which spans 1,700 acres or more than 2.5 square miles, includes an east basin, middle basin and west basin — each with its own set of issues. On the east basin, where Langseth lives, there are several steep banks along the nearly five miles of shoreline. The missing soil had to go somewhere, and it did — right to the bottom of the lake.

According to Langseth, the water in the east basin was six feet deep when he was a kid.

“Now, it’s four feet deep,” he said. “We’ve put millions of cubic feet of dirt into the lake. It’s not just from us. There’s other contributors here.”

Standing on the lake’s far eastern shoreline, Langseth pointed to areas on the northwest and southwest sides where erosion has also been an issue.

While the banks along his property feature 15- to 20-foot drop-offs, other areas of the shoreline have 5- to 8-foot cliffs.

“The issue is how do we solve (erosion),” said Langseth. “We can just let nature deal with it and in 400 to 500 years it will be equalized, but it doesn’t help ... water clarity. We keep smothering growth with every spring runoff.”

Implementing a project to reduce soil erosion on Langseth’s shoreline, while it will solve some issues, won’t address the overall health of Lake Ocheda. That’s where the watershed district comes in.

Lake-wide approach

While soil erosion is undoubtedly the biggest issue in the east basin, it is also impacting water quality and water clarity in the middle and western basins, where streambanks remain “fairly low and fairly stable,” said Langseth.

“Different areas of the lake have different problems,” he said. “What’s a problem for me may not be a problem for someone else.”

In recent years, the OOWD collected samples on the western basin of Lake Ocheda for testing on both water quality and water clarity. The results of those tests ultimately resulted in the lake being deemed impaired by the Minnesota Pollution Control Agency.

“Water quality (is impacted) by shoreline erosion, but it is also partially attributable to water high in nutrients, sediment and runoff from agricultural land,” said OOWD Administrator Dan Livdahl. “Part of the problem with water clarity is carp stirring up the bottom (sediments). Water clarity is so bad there are no longer the aquatic plants we would hope to see in a healthy lake.”

To address the overall health of the lake, Livdahl said the watershed board will recommend a variety of actions, including a lake drawdown to kill carp, consolidating the bottom sediment, stabilizing the shoreline, re-establishing aquatic vegetation and improving water clarity. As the lake is refilled, it would be restocked with fish.

OOWD Board President Les Johnson said with recent rule changes making it possible to do water quality management without 100 percent landowner buy-in, the watershed is “more hopeful” that improvements may be implemented.

“We’re hoping to get people who live along the lake to come forward with some ideas,” Johnson said. “We want it to be their plan and not our plan.”

“Any plan that we come up with that would affect the lake levels — lower the lake levels temporarily — has to be acceptable to 75 percent of the landowners and the DNR,” added Livdahl.

Implementation

Landowners on Lake Ocheda will gather in early 2010 to discuss the overall health of the lake and the steps that can be taken to improve water quality and water clarity. The meeting will include a PowerPoint presentation with shoreline photos taken on all three basins.

Langseth said he’s already visited with a handful of the landowners around Lake Ocheda.

“We’re open to all ideas,” he said. “Obviously, money’s going to be a big issue. You can’t afford to do everything you want to do.”

One of the least costly steps would be to complete a lake drawdown over at least one winter. The watershed could open up the dam on the southern tip of the west basin in the fall to lower the water levels, and the winter freeze would help to kill off the high numbers of carp in the lake. At the same time, it would kill the lake’s population of game fish such as northern pike and perch.

Livdahl said fish barriers would need to be installed to prevent roughfish like carp from reestablishing themselves in Lake Ocheda, but restocking the lake with predator fish, specifically bluegill, would also help. Bluegill feed on carp eggs and carp fry, which is crucial to the control of the roughfish. Female carp can lay up to two million eggs in a single season, he said.

By controlling the carp population, Livdahl said there will be less stirring of the sediment on the lake bottom, which would therefore promote aquatic plant growth and ultimately improve water clarity.

The aquatic growth would also benefit the Langseths on the eastern shore. Reeds, rushes and cattails growing along the shoreline would provide a buffer for rising waters in the spring and wave action throughout the spring, summer and fall. The plants would also help to stabilize the shoreline and reduce the potential for further erosion.

“We need to get landowner buy-in for the whole lake and a systematic approach for the whole watershed,” said Langseth. “Maybe within 10 years or 20 years, we can see a vast improvement on water quality within the entire watershed.”

Tags: lake ocheda, paul langseth, dan livdahl, stephanie mclain, les johnson, news, worthington, conservation, fishing