SWCD project saved resident's shoreline in storm
Nov 13, 2017 09:11AM
Winter arrived along the North Shore with a bang Oct. 27. Snow blanketed the area as Lake Superior showed a fury all its own, causing damage from Duluth's Canal Park all the way up to Lake and Cook counties.
Waves pounded the shore, causing erosion damage to lakeshore properties along Highway 61.
Just north of Two Harbors, one property lost a staircase leading down to the lake. At another residence, waves toppled several trees.
One property, however, was conspicuously unharmed during the storm.
Paul Fish, a retired railroad worker, purchased a piece of property just north of Betty's Pies on Highway 61. He planned to rehabilitate a cabin on the shore.
The cabin's basement had already been washed out and caved in, causing Fish to start over and rebuild the structure. His plan was to build on the footprint of the original basement, but since the building was going to be so close to the lakeshore, he needed a variance to allow him to build.
Lake County's environmental services department granted Fish the variance on the condition he work with the Lake County Soil and Water Conservation District (SWCD) to stabilize his shoreline. This would prevent his cabin from being washed away, like his neighbor's staircase, a stop an enormous amount of sediment from washing back into the lake.
Fish worked with local contractor Joe Mecklin and SWCD forester Tim Byrns to implement a plan to protect the shoreline from erosion and eventual collapse into the lake.
"He came to us with the problem of the bank instability at his property," Byrns said. "The bank instability is the result of an unstable toe (bottom of the slope). He originally had a 14-foot-high clay bank resting on bedrock along Lake Superior. It is constantly getting this wave action and it is affecting the toe of this clay. WIth an unstable toe, the waves are mostly interfering with where the clay meets the bedrock, causing it to slump."
Fish, Byrns and Mecklin worked together to create a plan to mitigate the erosion problems and reduce the sediment going into the lake from a culvert under Highway 61. The plan included placing 5-foot-wide "footer rocks" on the shore, excavating the clay and soil behind the rocks and refilling it with riprap (a mix of rocks piled on the shoreline to provide stability). Then clay was re-installed and compacted to create a more stable base.
The process also forced Fish to remove the vegetation, including all the trees, from the property. Fish didn't like the idea of removing the trees, but most of the vegetation on the parcel was either declining aspen or balsam fir — trees that don't have a long life span — and most on Fish's property were already at the end of their life cycle.
"I was not in favor of removing the trees and vegetation, but if you have a house that doesn't have a sound basement, the house is never going to be solid," Fish said. "You have to get down to the base to really rebuild it in a positive way."
The SWCD usually avoids removing vegetation in similar situations, but the dead or dying trees and scrub brush forced them to make a difficult choice.
"He's taking out those declining trees and replacing them with diverse conifers that are more representative of the boreal forest that is common along the North Shore," Fish said.
The SWCD also rolled into the project an extension of a culvert under Highway 61 into a pipe instead of letting the water run through an exposed channel, sending more sediment into Lake Superior.
Sediment running into the lake following the Oct. 27 storm caused the City of Duluth to ask residents to avoid using washing machines and dishwashers for a short time to allow its water treatment plant to catch up with removing sediment stirred up by the waves.
"Instead of having a situation where you have water going through this eroding incised channel, constantly depositing sediment into Lake Superior," Byrns said, "now, the water goes directly into the pipe and it goes cleanly into Lake Superior."
Fish said he is satisfied with the project, but it wasn't easy or cheap. The entire project is estimated to cost around $50,000, with a $10,000 cost-share grant from the SWCD.
"To prevent erosion of the lake, you can't put a Band-Aid on it," Fish said.