Shoreline erosion is the gradual wearing away of the land along the edge of a lake by waves, wind, ice, changing water levels, or human activity.
As water repeatedly strikes the shoreline, small amounts of soil are loosened and carried into the lake. Over time, this natural process can reshape the shoreline and contribute sediment to the lake.
Think of repeatedly brushing your hand across a pile of sand. Each pass removes only a little, but after many repetitions, the pile changes shape. Shoreline erosion works in much the same way.
A healthy shoreline protects both the lake and the surrounding land.
When shoreline erosion becomes excessive, it can:
For the Five Lakes watershed, protecting shorelines helps improve water quality while preserving the natural beauty and recreational value of the lakes.
Shoreline erosion occurs when the forces acting on the shoreline exceed the soil's ability to resist them.
Several natural processes contribute to shoreline erosion:
Wind-generated waves repeatedly strike the shoreline, loosening soil and carrying it into the lake.
During winter, expanding and shifting ice can push against the shoreline, dislodging soil, rocks, and vegetation.
Periods of unusually high or fluctuating lake levels can increase erosion by allowing waves to reach higher portions of the bank.
Strong winds create larger waves that increase the energy reaching the shoreline.
Rainwater flowing down slopes toward the lake can wash soil directly into the water.
Some activities can increase shoreline erosion, including:
Healthy shorelines are naturally protected by:
These features absorb wave energy and help hold the soil in place.
Myth: Shoreline erosion is caused only by boat wakes.
Fact: Boat wakes are only one of many factors that can contribute to shoreline erosion.
In many lakes, wind-generated waves are responsible for far more erosion over the course of a year than recreational boating. Ice movement, storms, fluctuating water levels, and the removal of shoreline vegetation can also significantly increase erosion.
Another common misconception is that a concrete seawall always provides the best protection.
While seawalls may be appropriate in some locations, they often reflect wave energy rather than absorb it. This can increase erosion at the base of the wall or on neighboring properties. In many situations, living shorelines—using native vegetation, natural rock, and gentle slopes—provide effective erosion protection while improving fish and wildlife habitat.
Many shoreline areas around the Five Lakes are naturally stable because they are protected by native vegetation, mature trees, and gentle slopes.
However, some shoreline areas experience increased erosion due to:
Although shoreline erosion contributes sediment to the lakes, studies in many watersheds have shown that other sources—such as streambank erosion and watershed runoff—may also contribute significant amounts of sediment. Understanding all sediment sources helps communities prioritize the most effective restoration and conservation efforts.
A strip of native shoreline vegetation only 10 to 25 feet wide can significantly reduce erosion, filter stormwater runoff, provide wildlife habitat, and improve the overall health of a lake. These natural shoreline buffers are among the most effective and economical tools available for protecting lakes.
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Channel erosion is the wearing away of a stream, creek, river, or drainage channel by flowing water.
Unlike bank erosion, which affects only the sides of a stream, channel erosion includes the erosion of the streambed (bottom), the banks (sides), and sometimes the overall shape of the channel.
Think of a stream channel as a natural roadway for water. Over time, flowing water can make that roadway wider, deeper, or change its course by removing soil and rock.
Channel erosion is a natural process, but it becomes a concern when it occurs faster than the channel can naturally stabilize itself.
Healthy stream channels naturally adjust over time by eroding some areas while depositing sediment in others. This balance creates pools, riffles, gravel bars, and important habitat for fish and wildlife.
However, excessive channel erosion can:
For the Five Lakes watershed, channel erosion is an important source of sediment that eventually moves downstream into connecting channels and lakes.
Flowing water naturally performs three functions:
A healthy stream channel maintains a balance between these three processes.
Channel erosion occurs when the force of flowing water exceeds the ability of the soil, rock, or vegetation to resist it.
Several factors influence channel erosion:
Faster-moving water has more energy and can erode larger amounts of soil.
Steeper channels increase water speed and erosion potential.
Loose sand and silt erode more easily than compacted soils or bedrock.
Roots from trees, shrubs, and grasses strengthen streambanks and reduce erosion.
Large storm events greatly increase water velocity and the stream's ability to reshape its channel.
Channel erosion may increase due to:
Scientists monitor channel erosion because it affects both water quality and the long-term stability of streams throughout a watershed.
Myth: Channel erosion is always harmful.
Fact: Some channel erosion is completely natural and necessary.
Streams naturally adjust their shape over time in response to changing water flow and sediment supply. This continual adjustment creates diverse habitats and helps maintain healthy stream ecosystems.
The concern is accelerated channel erosion, where human activities or unusually high runoff cause the stream to erode faster than natural processes can replace or stabilize the soil.
Another common misconception is that channel erosion only affects streams.
In reality, the sediment produced by channel erosion is carried downstream, where it may settle in lake inlets, navigation channels, wetlands, and reservoirs. This is why managing channel erosion is an important part of protecting downstream lakes.
Within the approximately 35,000-acre Five Lakes watershed, portions of the Little Elkhart River, tributaries, and drainage channels experience varying degrees of channel erosion.
During periods of heavy rainfall, increased water flow may erode both the streambed and streambanks. The eroded sediment is transported downstream toward Witmer, Westler, Dallas, Hackenberg, and Messick Lakes.
As water slows within the lakes and connecting channels, much of this sediment settles to the bottom through deposition, contributing over time to sediment accumulation.
Reducing excessive channel erosion upstream can help decrease the amount of sediment reaching the Five Lakes while improving stream habitat and water quality.
Healthy streams are constantly changing. Scientists often refer to streams as dynamic systems because they naturally adjust their width, depth, slope, and path over time. The goal of watershed management is not to stop these natural changes but to prevent excessive erosion caused by human activities.
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Surface runoff is water from rain or melting snow that flows across the ground instead of soaking into the soil.
As water moves downhill, it follows the natural shape of the land, eventually flowing into:
Along the way, surface runoff can carry:
Think of pouring a bucket of water onto a driveway. Because the water cannot soak in, it flows across the surface until it reaches a lower area. That is surface runoff.
Surface runoff is one of the primary ways water—and everything it carries—moves through a watershed.
It plays an important role in:
However, excessive surface runoff can also:
For the Five Lakes watershed, understanding surface runoff helps explain how rainfall influences water quality, sediment movement, and lake conditions long after a storm has ended.
When rain falls, it can follow four different paths:
Whether runoff occurs depends on several factors:
Heavy rain often falls faster than the soil can absorb it, creating more runoff.
Sandy soils usually absorb water quickly, while clay soils absorb water more slowly.
Forests, native grasses, and healthy lawns slow runoff and allow more water to soak into the ground.
Steeper slopes cause water to flow faster, increasing its ability to erode soil.
Roads, rooftops, sidewalks, and parking lots prevent water from soaking into the ground, producing much greater runoff.
As runoff gains speed, it has more energy to detach and carry soil particles. Scientists refer to this as erosion and sediment transport.
Because surface runoff originates across many acres rather than from a single pipe, it is considered a major source of nonpoint source pollution.
Myth: Surface runoff is always harmful.
Fact: Surface runoff is a natural and essential part of the water cycle.
Without runoff, streams, rivers, wetlands, and lakes would receive much less water.
The concern is how much runoff occurs and what it carries.
Healthy forests, wetlands, and grasslands naturally slow runoff, allowing much of the water to soak into the ground. In developed or heavily disturbed areas, runoff often occurs more rapidly and carries larger amounts of sediment and pollutants into nearby waterways.
Another common misconception is that surface runoff and stormwater runoff are different.
In most discussions, stormwater runoff is simply surface runoff generated by rain or melting snow in developed areas. Surface runoff is the broader scientific term, while stormwater runoff is commonly used in engineering and urban planning.
Within the approximately 35,000-acre Five Lakes watershed, surface runoff occurs after every significant rainfall.
Water flows across:
As it moves downhill, runoff enters drainage ditches, tributaries, and the Little Elkhart River, eventually flowing through Witmer, Westler, Dallas, Hackenberg, and Messick Lakes.
During heavy storms, residents may notice muddy water entering lake inlets. This is surface runoff carrying suspended sediment from across the watershed.
Reducing erosion, protecting wetlands, maintaining native vegetation, and improving stormwater management all help reduce the impacts of excessive surface runoff.
Not all rainfall becomes runoff. In a healthy natural landscape, a significant portion of rain infiltrates into the soil, where it replenishes groundwater and slowly feeds streams long after the storm has ended. Healthy soils act like a sponge, storing water and releasing it gradually.
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Nonpoint source pollution is pollution that comes from many small, scattered sources rather than from one single, identifiable location.
When rain or melting snow flows across the land, it picks up materials such as soil, fertilizers, nutrients, oil, pet waste, pesticides, leaves, and other pollutants. This runoff eventually carries those materials into streams, rivers, wetlands, and lakes.
Unlike pollution from a factory pipe or wastewater treatment plant, nonpoint source pollution does not come from one place. Instead, it comes from countless individual locations throughout a watershed.
Think of it like this:
Nonpoint source pollution is one of the leading causes of water-quality problems in lakes, rivers, and streams throughout the United States.
It can contribute to:
Because it originates from so many different places, nonpoint source pollution is also one of the most challenging water-quality issues to address.
For the Five Lakes watershed, understanding nonpoint source pollution helps explain why protecting water quality requires the cooperation of everyone living within the watershed—not just shoreline property owners.
Scientists classify pollution into two broad categories:
Pollution that enters a waterbody from a single, identifiable discharge point, such as:
These discharges are generally regulated through permits.
Pollution that is carried by rainfall or snowmelt over the land surface.
As runoff flows across the watershed, it may pick up:
These materials eventually enter drainage ditches, tributaries, streams, rivers, wetlands, and lakes.
Because runoff comes from many locations at once, it is difficult to measure or control through a single regulation.
Scientists reduce nonpoint source pollution by promoting Best Management Practices (BMPs) such as:
Myth: Nonpoint source pollution only comes from farms.
Fact: Nonpoint source pollution comes from every type of land use.
Potential sources include:
Another common misconception is that nonpoint source pollution is always caused by human activity.
Some materials carried by runoff—such as leaves, soil, and naturally occurring organic matter—are completely natural. The concern arises when excessive amounts of sediment, nutrients, or pollutants enter waterways and disrupt the natural balance of the ecosystem.
The goal of watershed stewardship is not to eliminate runoff, but to reduce the amount of harmful materials it carries into lakes and streams.
Throughout the approximately 35,000-acre Five Lakes watershed, rainwater flows across farmland, forests, roads, neighborhoods, campgrounds, and shoreline properties before entering drainage ditches, tributaries, and the Little Elkhart River.
Along the way, runoff may carry:
Because these materials originate from thousands of individual locations, they are considered nonpoint source pollution.
Protecting water quality in the Five Lakes requires reducing runoff and improving land management throughout the entire watershed—not simply addressing one location.
According to the U.S. Environmental Protection Agency (EPA), nonpoint source pollution is the nation's largest source of water-quality problems affecting lakes, rivers, and streams. This is why many watershed restoration programs focus on education, conservation, and voluntary best management practices rather than relying solely on regulations.
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Point source pollution is pollution that enters a lake, river, stream, or other waterbody from a single, identifiable source.
Unlike pollution that is washed across the landscape by rainfall, point source pollution comes from a specific location that can usually be seen, located, and monitored.
Examples include:
Think of point source pollution as water coming from a garden hose. You can clearly see where the water is coming from and where it enters the stream or lake.
Because point source pollution comes from a specific location, it is generally easier to:
Over the past 50 years, regulations and improved treatment technology have greatly reduced many forms of point source pollution in the United States.
For the Five Lakes watershed, understanding point source pollution helps distinguish between pollution that originates from a single discharge location and nonpoint source pollution, which comes from many scattered locations across the watershed.
Although point source pollution can affect lake water quality, many modern watershed management programs focus heavily on nonpoint source pollution because it is often more difficult to control.
Under the Clean Water Act, a point source is generally defined as any discernible, confined, and discrete conveyance from which pollutants are discharged into waters of the United States.
Examples include:
Because these discharges occur from known locations, they are typically regulated through the National Pollutant Discharge Elimination System (NPDES) permit program.
Permits often specify:
Scientists regularly monitor these discharge points to ensure they comply with environmental regulations and protect downstream water quality.
Myth: All pollution entering a lake is point source pollution.
Fact: Most pollution affecting lakes today comes from nonpoint sources, not point sources.
Point source pollution comes from one identifiable location.
Nonpoint source pollution is carried by rainfall or snowmelt across the landscape and originates from many different places.
Another common misconception is that every pipe entering a stream is carrying pollution.
Some pipes simply discharge:
Whether a discharge is harmful depends on what is being discharged and whether it meets environmental regulations.
Within the Five Lakes watershed, most water-quality concerns are associated with nonpoint source pollution, such as sediment, nutrients, and runoff carried into the lakes from across the approximately 35,000-acre watershed.
If a wastewater treatment facility or industrial operation were to discharge treated water into a tributary through a permitted outfall, that discharge would be considered point source pollution because it originates from a single, identifiable location.
By contrast, rainfall washing sediment from fields, lawns, roads, and shorelines into the lakes is considered nonpoint source pollution because it comes from many scattered sources.
Understanding the difference helps communities identify the most appropriate management strategies.
Before the Clean Water Act of 1972, many industries and municipalities discharged untreated wastewater directly into rivers and lakes. Since then, federal and state regulations have dramatically improved water quality by requiring permits, wastewater treatment, and regular monitoring of point source discharges.
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A riparian buffer is a strip of natural vegetation—such as grasses, wildflowers, shrubs, and trees—that grows alongside a stream, river, lake, wetland, or drainage ditch.
Think of a riparian buffer as nature's protective filter. Before rainwater reaches the water, it must pass through this band of vegetation. Along the way, the plants slow the water, trap sediment, absorb nutrients, and help protect the shoreline or streambank from erosion.
Healthy riparian buffers are one of the most effective natural tools for protecting water quality.
Riparian buffers provide many important benefits to both people and wildlife.
They help:
For the Five Lakes watershed, riparian buffers help reduce the amount of sediment and nutrients reaching the lakes while protecting the natural character of the shoreline and connected streams.
A riparian buffer works by slowing the movement of water before it reaches a lake or stream.
As runoff enters the buffer:
Slower-moving water loses energy, allowing soil particles to settle before reaching the water.
Plants absorb nutrients such as nitrogen and phosphorus for growth, reducing the amount available to fuel algae blooms.
Deep root systems improve soil structure, allowing more water to infiltrate rather than become surface runoff.
Roots bind the soil together, making streambanks and shorelines more resistant to erosion caused by flowing water and waves.
Riparian buffers provide food, nesting areas, travel corridors, and shelter for many species.
Scientists often recommend multiple layers of vegetation because each performs a different function:
The wider and healthier the buffer, the greater its ability to protect water quality.
Myth: A riparian buffer is simply an unmowed strip of grass.
Fact: While unmowed grass provides some benefits, a healthy riparian buffer usually includes a diverse mixture of native grasses, wildflowers, shrubs, and trees.
Another common misconception is that riparian buffers prevent people from enjoying their property.
In reality, many property owners design buffers that include:
while still maintaining most of the shoreline in natural vegetation.
Some people also believe riparian buffers are only useful along streams.
In fact, they are equally valuable along lake shorelines, drainage ditches, wetlands, and rivers.
Throughout the approximately 35,000-acre Five Lakes watershed, riparian buffers can be found along portions of the Little Elkhart River, tributaries, drainage ditches, wetlands, and lake shorelines.
Where native vegetation is present, these buffers help:
Expanding and protecting riparian buffers is one of the most effective long-term conservation practices for improving the health of the Five Lakes watershed.
Research has shown that a healthy riparian buffer can remove a significant percentage of sediment and nutrients from runoff before it reaches a stream or lake. Even relatively narrow buffers provide measurable benefits, while wider buffers offer even greater protection for water quality and wildlife.
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A buffer strip is a strip of permanent vegetation planted or maintained between an area of land use and a nearby waterbody to help protect water quality.
Buffer strips are commonly found along:
They are typically made up of grasses, wildflowers, shrubs, or trees.
Think of a buffer strip as a natural filter. Before rainwater reaches a stream or lake, it flows through the vegetation, where the plants slow the water, trap sediment, absorb nutrients, and reduce erosion.
Buffer strips are one of the simplest and most effective conservation practices available.
They help:
For the Five Lakes watershed, buffer strips help reduce the amount of sediment and nutrients entering drainage ditches, tributaries, and ultimately the connected lakes.
Buffer strips work by slowing water before it reaches a waterbody.
As runoff enters the vegetation:
Plants create resistance that reduces the speed of flowing water.
As water loses energy, soil particles settle onto the ground instead of entering the stream or lake.
Plants take up nitrogen and phosphorus as they grow, reducing the amount reaching the water.
The roots improve soil structure, allowing more water to soak into the ground rather than continuing as runoff.
Deep root systems hold soil together, reducing erosion during heavy rainfall.
Scientists often recommend buffer strips as one of the most cost-effective Best Management Practices (BMPs) for protecting water quality.
The effectiveness of a buffer strip depends on:
Generally, wider and more diverse buffer strips provide greater environmental benefits.
Myth: A buffer strip is the same as a riparian buffer.
Fact: A riparian buffer is a specific type of buffer strip located alongside a stream, river, lake, or wetland.
A buffer strip is the broader term and may also be installed:
Another common misconception is that buffer strips waste valuable land.
In reality, buffer strips often improve long-term land productivity by reducing soil loss, protecting water resources, stabilizing streambanks, and reducing maintenance costs.
Many farmers and property owners find that keeping highly erodible land in permanent vegetation protects both their property and nearby waterways.
Throughout the approximately 35,000-acre Five Lakes watershed, buffer strips can help protect water quality in many locations.
Examples include:
These buffer strips reduce the amount of sediment, nutrients, and runoff entering the Five Lakes while providing habitat for birds, pollinators, amphibians, and other wildlife.
Studies have shown that well-designed buffer strips can remove a significant percentage of sediment from runoff before it reaches nearby waterways. They also help slow floodwaters, recharge groundwater, and create valuable wildlife habitat.
Many conservation programs encourage landowners to establish buffer strips because they provide benefits to both agriculture and the environment.
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Messick Lake & RiverFront Association, Inc.