The purpose of upper bluff stabalization, as designed for your property is as follows, in order of importance:
- Provide a reduced slope and shelf at the top of the bluff (i.e. the bank or upper cliff), so as to provide an element of safety should the upper bluff area collapse or someone should fall.
- Stabalize the upper bluff by decreasing the slope and the saturated water weight on the area likely to shear, therby creating a landslide and losing additional valuable lakeshore property.
- Further stabalize the reduced slope area by terracing and planting native wisconsin prarie plants and shrubs, which are deep rooted and will thereby overtime, provide a lattice network of deep roots securing the soil. Prarie plants will develop roots to a 10-20 foot depth during there growth cycle.
- As an aesthetic benifit to the above, a thick growth of flowering native vegetation will aesthetically enhance your lake bluff area.
Other Options Include:
- French Drains can be installed parallel with your bluff at a set back of 20-30 feet, which will rapidly transfer rainfall and snowmelt during high precipitation periods, i.e. supersaturation.
- Burms can also be created to further re-direct the high intensity precipitation and snow-melt into the french drains, therby rapidly dewatering the area, which will reduce the weight of the bluff.
- Dewatering wells provide the rapid dewatering of the groundwater aquifer typically located between 40 to 60 feet below the top of your bluff. This sand lens which carries the shallow groundwater has a tendency to shear due to they water lubricity within the sand particles, this one to two foot sand lens is unstable during extreamley wet conditions, i.e. spring wet weather conditions/ snow melt as compared to the cohesive clay above and below the sand lens.
- Directionally drilled wick drains can be installed to intersect the groundwater aquifer and discharge further down the bluff above the high water mark. This method relieves the water pressure and back-flow pressure, which is characteristic of spring time high presipitation/soil saturation periods.
- Other options are also availble based on site specific conditions to include varied slope, vegetative cover, position of structures and their distance from the bluff face.
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