How Your Landscape Drainage System Affects Subsidence–For Good Or Bad

A closeup of the ground, with brown soil on the left side and various sizes of round stones on the right side. Also visible among the stones is a small green plastic cap that is part of an irrigation system.

If you’re like most homeowners, you probably think of your landscape as an extension of your indoor living space. Just like any other part of your home, it’s important to keep your landscape in good condition so that it can function how it’s supposed to. This includes getting an irrigation installation that will effectively and consistently water your lawn.

One thing you may not have considered, though, is that your landscape drainage system could be affected by the movement of the ground. So what is subsidence, and how does it impact your drainage? Let’s take a closer look.

What Is Subsidence?

Subsidence is the downward movement of the ground surface. It occurs when the supporting material beneath the surface, such as soil, rock, groundwater, or minerals is removed or compacted.

Land settlement can be a problem for both man-made structures and natural features. In some cases, significant land subsidence can cause buildings to collapse, and it can also lead to the formation of sinkholes.

In order to prevent land settlement, it is important to understand its causes and to take steps to stabilize the ground.

Read on to discover the most common causes of subsidence.

Causes Of Subsidence

Subsidence can happen for multiple reasons. However, the causes can be divided into two general categories: natural or human-caused. Natural causes include things such as weathering or animal activity. Land collapse caused by human activity includes such things as poor landscape drainage or mining.

Keep reading to learn more details about the various specific causes of subsidence.

Poorly Compacted Soil

Poorly compacted soils are more prone to movement because they settle more easily when wet and shrink when dry. When the ground is not properly compacted, it can settle over time, causing the ground to sink.

This often happens in landscapes where there is poor drainage. Waterlogged soil is much more likely to settle than dry soil, so land settlement is more likely to occur in wetter climates. This can cause serious problems in your landscape, including cracked foundations and sidewalks.

Weakened Or Damaged Foundation

Foundations that are weak or damaged can also cause subsidence. A damaged foundation can exacerbate the amount of waterlogged soil around your home and can lead to drainage problems. The first symptom of this issue is usually cracking in your walls and floors.

The most common cause of a weakened or damaged foundation is a lack of drainage. When the ground becomes saturated with water, it expands and puts pressure on the foundation. This causes the ground to settle and can eventually lead to walls cracking and even cause your home to sink into the ground. 

If you suspect that your foundation is weakened or damaged, it’s important to have it inspected by a professional as soon as possible. A damaged foundation affected by soil settlement can be a serious problem, but it can be prevented or repaired if you take action quickly.

Tree Roots Growing Into Sewer Or Water Lines

An underground water pipe, pushed and broken by big tree root, was dug out from the ground.

Another common cause of land subsidence is tree roots growing into sewer or water lines. When tree roots penetrate these underground pipes, they can cause the pipes to break or collapse.

This can lead to settlement in your landscape as the ground above the broken pipe sinks. Ground collapse can also occur if the tree roots clog the pipe, preventing proper drainage. For both these reasons, you should regularly inspect your sewer and water lines for any signs of damage or blockages. 

Excessive Groundwater Or Surface Water Drainage

Excessive drainage of groundwater or surface water is another common cause of soil settlement in your landscape. This can happen slowly over time, or it can happen suddenly after a heavy rainstorm. 

In order to prevent the ground from sinking, it is important to have proper yard drainage. The earth’s surface water should be directed away from buildings and foundation plantings, and groundwater should be allowed to seep slowly into the soil.

This means that you should only water your plants when they need it, and you should not overwater them, as this can exacerbate the issue. If you’re unsure of how often to water your plants, consult this complete guide to watering.

Land subsidence from mining or drilling

Human activities such as mining and drilling can also lead to land settlement. When subsurface materials are removed, the ground above them can collapse, resulting in a sinkhole.

Soil settlement can also occur when water is pumped out of the ground faster than it can be replenished. This can cause the soil to compact and the landscape to sink.

While this is probably the least common cause of ground settlement for most homeowners, it could be a possible cause if your land sits close to an active mine or if you recently had a well drilled.

Now that we have covered the main causes of ground settlement, let’s take a look at the primary types of subsidence that may be affecting your landscape.

Types of subsidence

Generally speaking, the types of subsidence can be divided into three broad categories:

Groundwater subsidence

When the water table falls and the soil begins to dry out, the ground can start to sink. This type of land settlement is most common in areas with a lot of groundwater use.

Settling Of Buildings Or Other Man-Made Structures

When heavy structures are built on soft, unstable soil, they can cause the ground to sink over time. While this type of land subsidence can be found anywhere, it is often found in areas with a lot of ongoing development.

Volcanic Subsidence

When an area is located over an active volcano, the ground can subside as the volcano erupts. This type of ground movement is common in Hawaii and other volcanic regions. Obviously, this type of soil settlement should not be a concern for most homeowners.

Now that you are familiar with the most common causes and types of subsidence, you may be wondering how you can identify this problem in your own landscape. Read on to find out!

How To Recognize Subsidence In Your Landscape

If you suspect that subsidence is occurring in your landscape, there are a few telltale signs to look for:

Cracks In Paved Surfaces

Cracks in paved surfaces, such as driveways or sidewalks, are a major clue that your landscape is sinking.

Cracks In Foundation or Door Issues

Another sign of ground settlement is visible cracks in your home’s foundation or walls. Doors that no longer close properly is an indication that your foundation is settling, which is also typically caused by subsidence.

Leaning Trees Or Shrubs

Finally, take note of any trees or shrubs that seem to be leaning or tilting. This is a sign that the subsoil in your yard is shifting due to subsidence.

If you see any of these signs, it’s important to take action immediately, since subsidence can cause serious damage to your home and landscape. This is why landscape irrigation is essential to your landscape design.

The Effects Of Subsidence On Your Drainage System

If you have subsidence in your yard, it’s likely that your drainage system is no longer functioning properly. Subsidence can cause problems for your yard drainage system because the subsided land may no longer be level with the rest of your property.

This can create depressions in your landscape that collect water, which can lead to problems with drainage.

Subsidence can also damage underground hidden pipes and other drainage infrastructures, such as a French drain or channel drain. As a result, excess water may pool in areas where it would normally drain away.

The lack of yard drainage can also damage your trees and other plants by uprooting them or causing them to tilt. Most types of plants and trees do not grow well in waterlogged soil so ineffective yard drainage could also eventually kill off the vegetation.

Potential Long-Term Consequences of Subsidence

Subsidence can have a number of potential long-term consequences for your landscape and home:

Consequences Of Subsidence On Your Landscape 

Sunken roads and sidewalks

As noted above, one of the effects of land subsidence around your home is sunken roads and sidewalks. Not only does this affect the aesthetic appeal of your home, but it can also actually exacerbate the subsidence problem since the depressions caused by your sunken walkways will collect water.

Damaged Pipelines and Sewer Lines

Subsidence can also create problems with utility lines and sewer pipes. As the wet ground settles, these lines can become dislodged or broken. A perforated PVC pipe can leak water and create more surface water in your yard. As a result, land subsidence can lead to costly repairs and disruptions in service. 


Red and white caution tape around a sinkhole in a grassy yard.

Finally, subsidence can create voids underground, which can collapse and cause sinkholes. Not only does a sinkhole create a potentially dangerous hazard in your landscape, but it can also further destabilize the foundation of your home.

Now that we’ve run through the consequences of subsidence on your landscape, let’s take a look at the potential consequences of subsidence on your home.

Consequences Of Subsidence On Your Home

Cracks In Walls And Foundations

The subsidence around your house can cause your foundation to settle, which in turn will create cracks in the walls and foundation. Again, not only will this make your home less attractive, but it can also create serious structural issues with the stability of your house.

Doors That No Longer Close Properly

As the ground settlement around or under your home causes your foundation to sink, the walls in your house will begin to shift. One of the first signs that this is occurring is when you discover that the doors in your home no longer close properly.

The best-case consequence is that you have to struggle to open or close your doors. Worst case it means that your house is becoming dangerously unstable.

Windows That Are Difficult To Open Or Close

Similar to doors that are jammed, windows that are difficult to open or close are another major consequence of the ground settling around your home.

Gaps Between Floors And Ceilings 

Another consequence of land settlement around your home is the appearance of gaps between your home’s floors and ceilings. This is due to the walls shifting because of the effect of subsidence on your foundation. This will negatively impact the aesthetic appeal of your home and could even affect the energy efficiency of your house due to air leaking through these cracks.

How To Prevent Or Mitigate The Effects Of Subsidence On Your Landscape Draining System

If left unchecked, the sinking ground can cause serious damage to your home or property, as well as create safety hazards. Fortunately, once you know what to look for, you can take steps to safeguard your landscape drainage system against this issue.

Read on to discover some simple things you can do to help prevent or mitigate the effects of subsidence on your landscape draining system.

Use Drought-Tolerant Plants

One step you can take is to choose drought-tolerant plants for your landscaping. Since ground settlement often occurs in waterlogged soil, using plants that don’t require frequent watering can help prevent subsidence from ever happening. Unsure of what plants to use? Check out this guide to drought-resistant plants perfect for Ohio.

Maintain Gutters And Downspouts

Make sure that your gutters and downspouts are in good condition and are draining properly. If your gutters are clogged or your downspouts are blocked, water will build up on your roof and eventually seep into the ground around your foundation, causing the ground to settle.

Check Your Landscape

Regularly check your landscape for any signs of sinking ground, such as cracks in sidewalks or driveways. Check your doors and windows to see that they are closing properly.

Get Inspected By A Professional

Finally, be sure to have your landscape regularly inspected by a qualified drainage engineer to ensure that everything is functioning properly and that there are no areas of showing signs of settling.

By taking these steps, you can help prevent or mitigate the effects of ground settlement on your landscape draining system.

As you can see, subsidence is a complex issue with many potential causes. If you think that your property may be experiencing the effects of land subsidence, it’s important to take action right away to prevent any long-term damage.

Contact Simmons Landscape & Irrigation

If you think you might have identified subsidence in your landscape, don’t hesitate to contact us at Simmons Landscape and Irrigation. Our team of experts will help you assess the situation and take steps to correct it before it causes long-term damage to your drainage system and other property.

Fill out our contact form today and one of our experts will help you get started!