The unseasonably wet summer that we’re experiencing is certainly causing some additional issues in our community, not the least of which are the several mud slides that we’ve experienced along the western shore in L and M Blocks. Back in July, the Association contracted with Lamp Rynearson Engineering and Kaw Valley Geotech to survey the damage, determine causation, and recommend possible solutions. The survey determined that the slopes below these lakeside homes have a thin soil mantle covering, consisting of approximately 3 feet of clay colluvium (mixed soil and rock fragments down washed from upslope) over interbedded shale and limestone bedrock. The natural slopes below the houses have been stabilized by the existing root systems of trees and the underlying woody shrubs and bushes on the slopes. These root systems stabilize the colluvium mechanically by naturally reinforcing and extending into the bedrock, also by removing excess moisture from the soil through transpiration. When the trees and woody shrubs are completely clear-cut to provide an open, grass covered view of the lakeshore and lake, the stabilizing deep root systems die. As the root systems decay, the soil slopes then begin to slide down toward the lake under the influence of gravity and seepage pressures within the slope.
Since construction of retaining walls or other mechanical solutions would be difficult and expensive due to the terrain, long-term stabilization will require the establishment of woody shrubs and trees that develop deep and extensive root systems. Trees and woody shrubs native to the Ozark area should be planted so that a stabilizing ground cover can be achieved that should require minimal maintenance. Trees such as Oaks of the Bur, White, Swamp White, Shumard, Black, and Northern Red varieties are native to the area and will grow well in the thin, poorly drained soils on the slopes. Deciduous shrubs such as the Japanese and Mentor barberry, Bayberry, Chokeberry, Lilac, Honeysuckle, Rose of Sharon, Spirea, Viburnum, and Weigela should also be used in the assortment of plantings on the slopes.
Unfortunately, in many cases where these problems have occurred, the slopes were adequately planted in many of these same species. However, in an attempt to improve their view of the Lake, some members decided to remove the very plantings that were holding the slope together. When the engineers were asked how we as an Association could prevent these problems in the future, they suggested a) increase educational efforts about the negative impact of clear cutting the slopes and b) increasing enforcement and penalties for performing these acts on Association property. I might add, that the Association Board of Directors has imposed a ban on removing trees on the Parkway that are larger than 1 inch in diameter.
Submitted by: Jan T. Olson – Executive Director
If you need to reach me for anything, please email me at [email protected] or call the office at 578-4272.