After a number of spring flooding incidents, the residents of Grasse Lane explored options to eliminating this all too often event. From this effort, it was discovered that the drain tiles leading from the parking lot, (located between the wetlands and the lake shore) to the lake had become almost totally blocked over the years. Root growth had compromised the system and water was no longer able to freely flow. The residents agreed to replace the drain tile and hopefully allow the high spring melts to properly be released to the lake.
As with many man-made improvements, we later discovered that the compromised drain tile system had in effect served as a filtering process for the water coming from the wetlands behind the lake. And, once this filtering was eliminated, the water coming from the wetlands was found to contain high levels of iron bacteria which precipitated out in a red-colored sediment, and at times as a reddish globbular substance (iron flocculate) attaching to anything it touched.
Iron bacteria occur naturally but are not desirable for residents. A similar but far more severe situation exists at Dead Pike Lake in northern Wisconsin, so we attended a DNR meeting Sept. 2017, in Manitowish Waters to see if we could learn from their work how to mitigate the problem we are seeing at Merrybrook. At this point we are in discussions with the DNR to assess initial findings from the Dead Pike Lake study to see if anything can be leveraged for our situation.
This is an on-going work and we will provide updates as we continue our work on this issue.
We are including a presentation on Dead Pike Lake that was given this April as an update to their work plan for remediation. Our problem comes from a similar cause but is much smaller in scope, thankfully.
The following documents provide information on this project.
|Presentation||2018||Sheboygan Bay Iron – Dead Pike Lake Presentation|