Shoreline erosion poses a great danger to waterfront properties. These erosive effects can lead to expensive damage, a loss of structural integrity, as well as environmental dangers. These forces have several causes. Knowing about them and their effects can help to protect your property and the environment in the future.
What are the Main Causes of Shoreline Erosion?
Shoreline erosion is a natural process by which soil is removed gradually from the shore. We expect this removal of soil to occur to some degree. The problem becomes worsened due to human influences compounded by natural causes. The effects can lead to quicker soil removal around coastlines, streams, rivers, and lakes. Rapid shoreline erosion poses potential headaches for property owners and serious repercussions for the environment.
What Human Influences Lead to Rapid Erosion?
When human beings are responsible for quickened shoreline erosion, we call this accelerated erosion, which is more difficult to reverse than natural soil erosion. Preventing the destructive forces caused by human beings can be accomplished through professional guidance. Here are two examples.
Vegetation Removal
Shorelines rely on plant roots that function as natural barriers against soil erosion. The roots of aquatic plants that grow in shallow waters help to reduce the energy produced by waves before the destructive force can reach the shore. This energy produced by waves is one of the natural forces that cause soil erosion. When vegetation is removed from the shore, the energy barrier no longer exists, which means the ground will be fully impacted by the waves’ erosive force.
Seawall Installation
Installing a seawall adds an additional barrier along the shore that can further prevent the continuous impact of waves. While natural vegetation and roots provide an absorbent barrier, a seawall lends to a hardening of the shoreline. This combination of shields against wave forces prevents accelerated erosion. Wave energy is typically directed downward. When a wave hits the shore, the soil is displaced along the bottom of the waterway. This makes the body of water deeper. Over time, the seawall will no longer be effective. To prevent accelerated erosion, it is more effective to direct the wave’s power sideways via wave flanking, which causes neighboring properties to receive greater amounts of erosion damage instead.
What are Some Natural Causes of Shoreline Erosion?
The natural forces shoreline property owners should be most concerned with include aquatic forces or water forces. These forces can be exacerbated by groundwater movement, wind currents, and temperature changes.
Erosion By Waves
Waves displace soil at a rapid pace, particularly in areas where natural vegetation has been removed. Properties along the shoreline are prone to frequent wave attacks caused by natural occurrences (wind currents) and also boats. Planting vegetation and keeping roots in place are control methods that can minimize soil erosion.
Ice Erosion
During the colder months, ice sheets can be pushed onto the shore from frozen lakes when they melt. This phenomenon can increase in frequency as water levels rise. This makes lakeside areas with rising water levels and freezing temperatures more at risk for rapid erosion.
Stormwater Erosion
Stormwater can cause heavy displacement where the soil is loose, depending on the slope of your property. Sheet erosion can also occur, which causes even layers of earth to be carried over the property’s surface.
Preventing these soil erosion from these natural forces can be accomplished with professional landscaping solutions designed to safely prevent soil removal on your property.
How are Waterfront Properties Affected by Soil Erosion?
Shoreline erosion can be expensive. A single foot of shore recession to a 100-foot property can amount to cost-per-square-foot losses of $9,000 and up. As the shoreline continues to erode, the costs will keep adding up. These losses may be tabulated in building repairs but also in a depreciation of the property’s overall value. Current estimates state that coastal erosion currently resides at .5 to 2 meters each year.
Soil erosion does not only affect your pocketbook. Rapid shoreline erosion can also:
Weaken the structural integrity of your hard-earned assets.
Endanger any inhabitants of nearshore buildings.
Make your living environment unpleasant.
Disturb the natural ecosystem, affecting wildlife, water quality, and natural resources.
Shoreline erosion points to a weak foundation on the shore, which in turn indicates weakened structural integrity for waterfront properties. With the foundation compromised, all nearshore buildings are suddenly at risk for damage. That includes walls, ceilings, gas, plumbing, and electrical systems. Drinking and bathing water can also become affected, making it cloudy or filled with algae overgrowth.
You don’t have to live with the natural phenomenon of soil erosion. You can instead protect your property with several methods humans have invented to keep homes and property along the shoreline fortified against soil removal.
What are the Best Shoreline Erosion Control Methods for Property Owners?
Property owners have several shoreline erosion control solutions to choose from. You should be aware that each state has a regulatory agency for shorelines that dictates which erosion control methods can be used. Ignoring those specifications can lead to monetary fines.
When looking for a way to control the erosion around your property, you should look for a solution that is cost-effective, environmentally friendly, easy to maintain, and aesthetically appealing. Here are a few to consider.
Water Runoff Diversion
High bluffs can be particularly damaged by increased water runoff. Bluff erosion control can be managed by diverting surface runoff with rain gutter outlets, strategic landscaping, or a French drain installation. If it is not possible to divert the runoff, the rate of runoff can be reduced by creating safe water routes and limiting groundwater flow toward the high bluff.
Other ideas include minimizing paved areas, avoiding additional weight caused by buildings, vehicles, and storage sheds on the bluff edge, installing septic systems, pools, and drain fields away from the bluff, and retaining moisture-absorbing vegetation on the bluff itself.
Bulkhead Seawalls and Rock
Installing seawalls, which was one of the human interventions we mentioned to prevent rapid erosion, can stop shoreline soil from becoming displaced. This hard method of erosion prevention will redirect energy from forceful waves, but only for a brief time. Installing concrete and stone retaining walls will eventually cause problems for the property owner and the environment.
These problems occur due to the nature of the energy that crashes to shore from repeated wave activity. In a natural landscape, native vegetation absorbs the wave energy upon impact. Seawall erosion control causes the energy of the waves to impact the shore instead. While the full force of the wave is prevented from reaching the coast, the energy must be redirected downward to the water’s bottom or sideways to a neighboring property. Either direction causes increased erosion rates, environmental harm, and structural damage.
Wave energy directed downward scours the lake, making the water deeper. Eventually, the water will deepen so much that the seawall or bulkhead will no longer be as effective.
When wave energy is directed to the side, or at an angle, this causes wave flanking. This in turn can increase structural damage and rates of erosion on neighboring properties. The act of installing a seawall or bulkhead and future repairs can increase erosion for your neighbors on either side of your property.
Therefore, a seawall or bulkhead is a short-term erosion control method with long-term effects on your waterfront property, neighboring property, and the environment.
Shoreline Vegetation
We have covered how native shoreline vegetation serves as a natural barrier against the forces that lead to erosion. The same can be said for beach rocks. Removing vegetation and rocks can accelerate natural deterioration and can lead to a number of problems for property owners. If roots and rocks have already been removed along the shoreline, consider reestablishing and maintaining these barriers to prevent future soil removal.
Erosion is best controlled with sedges, grasses, shrubs, flowers, and trees. Planting these varieties of aquatic vegetation is known as biotechnical erosion control or BEC, which helps to prevent low to moderate erosion.
Permanent Erosion Control Mats
Flexamat works with vegetation to offer a permanent solution to stop shoreline erosion while aesthetically conforming to the landscape. Flexamat stops erosion caused by waves, ice, burrowing of muskrats/nutria and erosion caused by fish, such as Tillapia. Flexamat enables safe maintenance of the shoreline. Commercial mowers may be used over Flexamat or allow native vegetation to grow wild.
Flexamat enhances safety. Steep eroded banks make it hazardous to maintain or even walk along the shoreline. Many municipalities have regulations that ensure minimum slope requirements. Flexamat helps provide a stable walking surface if using the shoreline as an entry point for canoes or kayaks.
Eroding sediment from shorelines is a major source of pollution. The eroded sediment has many negative impacts with natural ecosystems, such as making the water shallow, which can lead to artificially warmer water temperatures. Flexamat re-enforces natural vegetation and locks the shoreline permanently in place.