How To Dig a Trench in Clay Soil


Clay soil can be difficult to work on because they’re often very dense and sticky. This article is focused on how to dig a trench in clay soil. I will cover common methods that can be used in getting things done.

Digging A Trench In Clay Soil By Hand

Digging a trench by hand can be extremely difficult, though not impossible for the average person.

Planning: This is no doubt the most important aspect of the task. Ensure you’re digging in areas that would not cause damage to your yard, garden, or house. It’s important to work with the natural topography of the land. This means, digging the trench along the natural erosion path, a slope. But if you can’t find an easy slope, you can still make do with a flat surface.

Once you have decided on a location, mark it out with a surveyor’s line and clear the area of top grass and excess dirt. This is important, to give you an overview of the layout you’re working with.

Approach: Take a spade and carefully create a cut hill along the length of where you plan on digging. You need to have 3-4 inches depth from where the bottom of the trench will be.

Once you’ve marked this cut hill, the next step is to determine how deep your trench needs to be, usually, about 6 inches (15 centimeters) will work fine, this is a reasonable depth if you’re not using any heavy equipment or tool. Since the plan is to dig by hand, your best tool would be a shovel with sharp edges. You can use any of the shovels we reviewed in this article, as they’re perfect for the purpose of digging.

Typically, a simple trench should be dug in a square shape. This allows you to move the dirt from one side of the trench to the other, making it easier for digging.

Once you have your square dug, remove any sticks or branches that might be left inside. Take a spade and make another cut along the bottom of the trench, repeat the process until significant progress is made along the marked path. If you’re working with a flat surface, you would have to create a slope within the trench.

To create a slope, take a spade or shovel and place it on the ground of the trench that’s closest to you. Push back with your body weight and scoop dirt from the trench into your shovel, tilting backward as you push. Repeat this process until the entire trench slopes down towards one end.

Once you’re done digging, it’s time to put water-permeable material in the trench. This will allow water to seep into the ground.

A simple material you can use is gravel. It works perfectly well for absorbing excess water without being too expensive or difficult to acquire. Carefully lay gravel along the trench in a single layer. This ensures water can pass through and flow freely within the ground.

Digging A Trench In Clay Soil With Power Tools

When you have access to tools such as power-diggers, things are much easier. However, keep in mind that you should still take care when digging with power tools. Use protective gear to avoid injuries and accidents!

Planning: Just like before, map out the area where you plan on digging your trench. Ensure you have enough space for the machine to work without breaking any fences or damaging yard equipment.

Approach: Depending on how big your trench is, some tools may require more than one person to operate them safely. But the approach is quite similar, dig in squares, and ensure the trench slopes towards the end.

Best Tool For Digging In Clay Soil:

There are plenty of tools out there that can help you with digging in clay soil. The most popular ones are power diggers, also known as trench diggers or hydraulic shovels. These tools can really make your job a whole lot easier when it comes to digging in clay soil. But trench diggers or hydraulic shovels are often not necessary when you’re working on a small trench in your backyard or garden. Some simple tools to get your started include:

Spade: A spade is a must-have tool for digging in clay soil. It’s the easiest and cheapest way to get started, although it will take a lot more time than a power digger. But if you’re working with a tiny trench or something that isn’t too deep- you can get away with using just a spade!

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Trench shovel: The trench shovel shares a lot of similarities with the spade, but it digs deeper and removes more material at once. This is great if you’re working on a bigger project and don’t want to spend too much time digging.

Hoes: This would help in clearing the top grass or dirt before you begin digging. If the surface is too hard, you might want to use a pickaxe or break it up with a spade- before using any tools.

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Surveyor’s Line: For a more accurate and efficient dig, you can use a surveyor’s line for marking where the trenches should go. This will help you get the perfect shape and size depending on your needs.

FAQ On How to Dig A Trench In Clay Soil

How do you dig a trench in clay soil?

Because of the density of clay soil, it’s not easy to work with as compared to other types of soil. But the approach is not very complicated once you have access to the right tool. Using your spade or shovel, push into the ground and tilt backward to raise the soil into your shovel. Dig in squares, a small square at a time.

Is clay easier to dig wet or dry?

It is easier to dig clay soil when it is dry. Wet clay is difficult to work with because they are denser and stick to your tools.

What do you use to dig in clay soil?

Not all traditional tools are effective when digging in clay soil. A spade or trench shovel is your best bet to break through the surface without too much effort- although it will take more time than using a power digger.

Caution Before Digging A Trench

In most cities, utility cables such as power, water, and internet cables are buried beneath the ground. It is important to contact the local authorities and have them check the area to mark any underground cable path before you start your project since you will be digging into the ground. Make sure you’re not digging in the wrong location or you might have to deal with a lot of problems later on.