Healthy shorelines are as valuable to people as they are vital to lake ecosystems. The area where land meets water can be both captivating and calming, and is a primary focus for many recreational activities.
Known as the “ribbon of life,” the shoreline provides important food sources and habitat for 80-90% of freshwater species. Added to this, because they are a meeting place of upland and lowland, the shoreline provides essential support for land-based wildlife too, from birds, to minks, and moose.
The “shoreline” however, is not a mere “ribbon”; the shoreline typically refers to an 100-foot band beginning at the littoral zone (about 3 feet into the lake) and stretching far into the upland area. The shoreline is often a majority of a residential lot.
In their natural state, shorelines can be remarkably resilient and self-sustaining. Rocks and the deep roots of native plants along the shore help prevent erosion from wind and wave action, protecting the lake’s habitats and landowner’s properties. Shoreland vegetation also acts as a filter, guarding the lake against the runoff of harmful excess nutrients or contaminants. This area is sensitive to excessive use and common human activities. Careful considerations are therefore needed to balance human recreation with lake conservation.
Natural Shoreline Features and Functions
Natural shorelines have three key areas that are crucial for maintaining a healthy lake: the littoral zone, the riparian zone, and the upland zone.
- The littoral zone is the shallow water near the shore. It begins at the water’s edge and extends out to the area where sunlight no longer reaches the lake’s bottom.
- The riparian zone is the land by the shoreline, from the water’s edge up to the area where dry land begins. It is the transition zone where terrestrial and aquatic environments meet.
- The upland zone is the higher and drier land that extends beyond the riparian area.
Although these zones have some distinct features, they are interconnected and gradually transition into each other almost seamlessly.
Maintaining the integrity and connectivity between these zones is important for lake health and the survival of the many species that contribute to and depend on a healthy lake environment.
Riparian areas occupy a small percentage of land but usually have a more diverse range of plants and animals than upland areas.
Aquatic vegetation, wood debris, and rocks in the littoral zone are critical components of healthy lake habitats. Plants help supply the lake with oxygen and are important food sources for many aquatic species. Logs and rocks provide essential spawning grounds and nursery areas for fish. Combined, these features also offer places for rest and refuge for the lake’s inhabitants.
Vegetation in the riparian and upland zones form a protective barrier against the runoff of contaminants from land to water. These natural buffer zones absorb a substantial amount of excess nutrients (from leaky septic systems, the use of fertilizers, and deposits from pets, for example) before they reach the lake. Without this protective barrier, the influx of nutrients such as phosphorous into the lake (a process known as eutrophication) can cause harmful algal blooms, which lower the lake’s water quality, reduce its oxygen levels, and destroy ecosystems.
Foliage in the riparian and upland areas also keeps the shoreline cool and intact. Tree canopy creates shaded areas that regulate the lake’s temperature (cooler lake temperatures mean more oxygen for fish and other aquatic life), and thick layers of vegetation help prevent erosion. Leaves and branches reduce the impact of rain on the shore, for instance, which is further reduced by ground cover such as leaf litter, pine needles, and fallen twigs. Below ground, the deep roots of native plants, shrubs, and trees absorb the excess moisture and their diverse roots form a complex web that acts as a “glue,” holding the shoreland together.
Natural shorelines provide food and shelter for terrestrial species as well, and are safe travel corridors for wildlife. It is therefore important to preserve the features of these zones and connectivity between them to benefit life on the land and in the lake.
Shoreline alterations intended to “improve” the waterfront by removing its natural features (vegetation, rocks, wood debris) and replacing them with sand or hardened shores are harmful to landowner’s properties, the lake, and lake ecosystems. These alterations can limit or eliminate the shoreline’s potential to function as a protective barrier against erosion and contaminants, and remove important habitat and food sources for the numerous species that depend on them.
Preserving natural shorelines, or restoring shorelines to their natural state, can benefit the lake and lake residents in a variety of ways. For example, natural shorelines:
- Protect the lakes’ water quality
- Provide habitats for fish and wildlife
- Provide shade from the sun and relief from the wind
- Reduce noise and dust
- Reduce erosion and help prevent flooding
- Reduce the amount of time and money spent on property maintenance
- Provide privacy and screening against social crowding
- Provide an instant learning ground and playground for children and youth
Landowners can reach their intended goals (such as preventing erosion, creating better swimming and docking areas, and improving the view) in ways that benefit people, the lake, and the lake’s inhabitants. These actions are not only easy and inexpensive, but also provide spaces where both people and the lake environment can thrive.
Gently sloping soft shorelines, particularly those covered in a diverse range of native plants, are more effective in shoreline stability and erosion control than artificial, hardened shorelines. Replacing native vegetation with wall-like structures (even small walls) is a costly, temporary, and unnecessary “fix” when it comes to protecting shoreline properties. The force of backwash from breaking waves against hardened surfaces can also harm nearby habitat and nearby properties. In other words, artificial or hardened shorelines have little benefit to the landowner, the lake, or the lake community. Natural or softened shorelines, on the other hand, are inexpensive and nearly maintenance-free, saving the landowner money and valuable time that could be spent enjoying what a healthy lake has to offer.
Play and Preservation
Some common alterations made to natural shorelines to improve recreational areas can have devastating impacts on the lake environment. Compromises can be made, however, to balance outdoor recreation with shoreline preservation.
On the Land
Lawns consisting of short, shallow-rooted grass can create open spaces for outdoor activities and easier access to the water, but they lack the absorbency needed to protect the lake from runoff. Mowing the lawn to the shore also increases the risk of erosion and flooding, and destroys habitats. Open areas with fertilized lawn also attract geese! Geese are tundra species that require open and wide sight lines to thrive. Their guano contains a bacteria that can be harmful to humans, and high nitrates that can reduce oxygen availability in lakes.
Landowners can enjoy open spaces while protecting the lake by establishing a “no mow zone” along the shore. Preserving taller, native vegetation helps maintain the lake’s natural protective barrier, or buffer zone. A minimum of 30 feet is recommended for adequate filtration and habitat preservation (100 feet is better). In general, steeper shores or shores with finer soil particles typically require larger buffer zones for optimal functioning.
At the Shore
Sand that is imported for sunbathing and wading areas is a temporary addition to the shoreline that can have long-term negative impacts on the lake environment. Sand along the shore ends up in the lake, causing siltation. When siltation occurs, the fine particles in the water can smother and suffocate fish eggs, bury mayflies in their burrows, and cover cracks, crevices, and vegetation that fish, frogs, and toads depend on to lay their eggs. To enjoy the sand and protect the lake, setting a beach back from the shoreline (especially one that is more like a sandbox and in the upland zone) can be a good compromise. Forgoing the sand altogether is even better. Maintaining the shoreline’s vegetative buffer also helps prevent soil from land erosion having the same effect on the littoral zone as sand.
In the Water
Fewer rocks, vegetation, and wood debris in the water can improve swimming and docking areas for people, but can be disastrous for the lakes’ inhabitants. Removing these natural features means removing essential oxygen sources, food resources, and habitats for many aquatic species. Clearing an area for swimming and boating safety while maintaining areas for aquatic vegetation and other features can be a good compromise. Simply adding a buoy, flag, or other indicator of these elements is even better because it can help swimmers and boaters navigate through the waters while keeping these areas intact. For fewer aquatic plants, preventative measures are best. Limiting the amount of excess nutrients that enter the lake by monitoring what goes on the land (e.g., reducing or avoiding the use of fertilizers) and maintaining the shoreline’s natural buffer zone can help ensure there is a healthy balance of aquatic vegetation – enough for a healthy lake, but not too much to pester people or pollute the lake environment.
Docks can also be used as a bridge to bypass aquatic vegetation in shallow waters. Floating and cantilever docks have the least impact on wildlife. To learn more about building or repairing docks that minimize harm, see the Dock Primer: A Cottager’s Guide to Waterfront Friendly Docks, produced by Fisheries and Oceans Canada and Cottage Life.
Lake Views and Landscaping
The view of the lake can be improved while maintaining the natural shoreline. Pruning trees (instead of removing them) enhances sight lines while protecting and maintaining important habitat for birds, fish, and other wildlife. Trees also benefit the landowner by guarding against erosion and providing shade, privacy, and shelter from wind, dust, and noise.
Don’t like the look of the vegetation along the shoreline? You can design your own shoreline garden with beautiful native plants to enhance your shoreline’s aesthetics while improving or maintaining a functioning and flourishing buffer zone. Having an assortment of plants that attract birds and butterflies can create a beautiful, lively property for you and your family to enjoy, and a bountiful lake environment for wildlife to thrive.
For more information on shoreline designs, attend a Design Your Own Shoreline Garden workshop.
Thinking of re-naturalizing your shoreline? The Natural Edge site visits are also available to help you with your project.
In the Ribbon of Life video, Professor Barb Elliot (Ecosystem Management Program, Fleming College) discusses important aspects of a healthy shoreline, including its composition, structure, and function.
As a follow-up to the Ribbon of Life video, the Beginner’s Guide to Shoreline Stewardship describes simple actions at the shoreline that can protect lake health for future generations.
References and Reading Resources:
A Shoreline Owner’s Guide to Healthy Waterfronts, produced by the Federation of Ontario Cottagers’ Associations
A Shoreline Owner’s Guide to Lakeland Living, produced by the Lakeland Alliance
The Shore Primer: A Cottager’s Guide to a Healthy Waterfront, produced by Fisheries and Oceans Canada in Association with Cottage Life
Take the Plunge: A Guide to Stewardship of Ontario’s Waters, produced by the Federation of Ontario Cottagers’ Associations