Shoreline Survey Completed on Lake Charlevoix
How does your greenbelt rate? Do you have erosion, algae?
As you know, protecting the natural beauty and quality of Lake Charlevoix is the number one goal of the Lake Charlevoix Association. With that in mind, every five years we participate with Tip of the Mitt Watershed Council as they survey our lake shore and work with landowners to lessen their impact on the lake. Lake shorelines are the critical interface between land and water where human activity has the greatest potential for degrading water quality. Developing shoreline properties for residential, commercial, or other uses invariably has negative impacts on the lake ecosystem. During the development process, vegetation is removed; the terrain is graded; utilities are installed; structures are built; and areas are paved. These changes to the landscape, and subsequent human activity in the shoreline area, have consequences on the aquatic ecosystem. Nutrients from wastes, contaminants from cars and roads, and soils from eroded areas are among some of the pollutants that wash into and degrade the lake following shoreline development. We encourage everyone to learn how your shoreline rates and to work to improve your greenbelt. See related “Lake Guardian” article.
In 2012, Tip of the Mitt Watershed Council staff and interns, with funding from the Charlevoix County Community Foundation, surveyed the entire 60+/- miles of shoreline on Lake Charlevoix. Each of the over 1700 individual properties fronting Lake Charlevoix was carefully analyzed and Cladophora algae (a biological nutrient pollution indicator), erosion, greenbelts, and alterations (e.g., seawalls, beach sanding) were documented.
A greenbelt, in the context of lake management and this survey, is the vegetated area along the shoreline. A healthy greenbelt, consisting of a mix of native trees, shrubs, and herbaceous plants, provides many benefits to the lake ecosystem, including shoreline stabilization and erosion control, habitat for shoreline-dependent species, infiltration of runoff, and filtration of pollutants, such as sediments, nutrients and chemicals. Please note that we do not consider turf grass part of the greenbelt because it does not provide the same benefits that a mix of native vegetation does and turf maintenance can potentially degrade the lake’s water quality. Individuals can also find township zoning requirements for greenbelts in your township at www.lakecharlevoix.org/zoning.
Results from the 2012 survey were tabulated and can be viewed at www.lakecharlevoix.org/lake-charlevoix-shore-survey. To find the confidential results for your property, please find the 4 digit, randomized code on your mailing label or in your letter, then click on the link above and scroll down to find your code number. The total greenbelt was rated on a scale of 0-7 with 7 being the best. If you received a high number, great job, keep encouraging those native plants. If your rating was a low number, please feel free to contact LCA using firstname.lastname@example.org. We will be working to help people identify and address issues where concerns were found. Native plants and a robust, filtering greenbelt can be a beautiful addition to the shoreline that will help protect the lake forever. We hope we can count on everyone to work to improve theirs.
Some lake residents may soon receive questionnaires and/or letters concerning property characteristics and management, which we strongly encourage you to complete and return, so that we can work together to determine if there are problems on your shoreline AND find solutions.
The following are descriptions for the column headings in the Lake Charlevoix Association Database.
Cladophora: a type of algae that occurs naturally in our lakes, but grows densely when excess nutrients are available, whether from natural sources such as a stream flowing into the lake or from cultural sources, such as yard fertilizers, malfunctioning septic systems, or storm water. Cladophora was used as a biological indicator of nutrient pollution during the survey and when observed, it was described in terms of relative growth density (the heavier the growth, the stronger the signal of nutrient pollution). Although somewhat subjective, growth density was determined by estimating the percentage of substrate covered with Cladophora using the following categorization system:
*Very Light is noted when a green shimmer is noticed on hard substrate, but no filamentous growth present. Very Heavy overlaps with heavy and is distinguished by both high percentage of substrate coverage and long filamentous growth.
Habitat: Cladophora growth is dependent on the amount of suitable substrate present because it will generally only grow on hard substrate, such as gravel, rocks, and wood. Habitat was assessed on each property using the following: Y=Yes (habitat available throughout shoreline), N=No (no habitat available), P=Partial (some areas of the shoreline had suitable habitat and others did not).
Substrate: lake bottom types in the splash zone along the shore were noted during the survey using the following abbreviations: M = soft muck or marl, S = sand, G = gravel (0.1” to 2.5” diameter), R = rock (2.5” to 10” diameter), B = boulder (>10” diameter), W = woody debris, and MTL = metal seawall or other.
Greenbelts: the shoreline vegetation present at each property was rated based on seven criteria. Positive points were given for 1) the percentage of shoreline length with vegetation (not including turf grass), 2) the average depth of the greenbelt from the waters edge landward into the property, 3) the variety of vertical structure in the greenbelt including overstory, understory, and groundcover, 4) the density of the shoreline vegetation, and 5) the variety of species present in the greenbelt. Negative points were given for 1) the percentage of shoreline with turf grass extending to or near the water’s edge, and 2) shoreline alterations, such as riprap, seawalls, groins, and boathouses.
Greenbelt ratings for each parameter were summed to produce an overall greenbelt score representing greenbelt status or health. The following table shows scores, which ranged from -7 to 17, and corresponding ratings.
Erosion: was noted based on shoreline areas that exhibited: areas of bare soil, leaning or downed trees, exposed tree roots, undercut banks, slumping hunks of sod, excessive deposits of sediments, or muddy water. Similar to Cladophora, shoreline erosion was recorded on field data sheets with estimates of its extent and relative severity (light, moderate, or heavy/severe). For example “Mx20” indicates 20 feet of shoreline with moderate erosion. Additional information about the nature of the erosion, such as location and potential causes, was also noted.