Land drains, commonly referred to as perforated drain pipes, are often utilized in domestic, commercial, industrial, as well as agricultural areas to prevent waterlogging. The ground can get waterlogged because of excess rainfall or certain impermeable soils such as clay. Removing the water and channeling it elsewhere can help prevent stagnant water, poor irrigation of fields, and flooding of nearby areas.
Different types of land drains
Typically, there are two different types of land drains: land drain coils plus twin-wall land drains. Both of them are created with PVC and come in various diameters and lengths suitable for different applications. 25m and 50m are the two most common coil sizes (length) though grater, specialist lengths are also available from certain manufacturers.
Ducting features a universal color code system, which guarantees the safety of the pipe and those working around it. However, land drains lack this system. They’re generally black in color and this doesn’t relate with the contents in an anyway since this should only be water.
How they work
Land drains usually work by directing water towards a pipe in waterlogged areas. Soil saturation prevents the absorption of water, causing the ground to become waterlogged. This often occurs due to the type of soil as well as the amount of rainfall.
Thanks to drain pipes, water can now flow naturally down a layer of aggregate into the pipe perforations.gutter
Once water is inside the land drain pipe, the water is channeled to the designated disposal point. It does so with the help of a gentle gradient on install. A land drain typically features a layer of loose aggregate surrounding it so that water has a clear direction to flow in when it can’t gain access to the compacted as well as saturated soil.
Most often, the water coming from a land drainage system is directed to 1 of 3 possible places. For instance, it can be channeled to a nearby water source such as a stream or river, but with the approval of the Environmental Control Agency. Besides, it can as well be directed to a nearby soakaway system or a storm drain.
Where to install your land drain
Land drains are often installed in waterlogged areas or where the soil hasn’t performed well in a percolation test. With the help of a local drainage firm, it’s easier to establish if your land or garden is at risk of waterlogging. This is often achieved through a percolation test. Of course, you can conduct a DIY percolation test but for bigger land, it isn’t worth the risk when there are many professional companies out there who might offer a free test.
Check with your local authority to ensure that they approve your intent to deposit the water from your land drain system at a given site. Water sources are sometimes protected by local authorities, so make sure that everything is assessed and ratified. Failure to abide by the council policy can put you at risk of large fines.
It’s also important to note that storm drains feature a maximum capacity, so the council will provide you with a maximum flow rate which indicates how many liters of water per second are allowed to flow into the storm drain. Exceeding this range means that you risk flooding the storm drain while backing up your land drain.
Installation tips for land drains
It takes the right skills and expertise to correctly install a land drainage system. However, some people choose to perform the procedure on their own. And this really depends on the nature and terrain of your land. If it’s flat, you shouldn’t experience much trouble trying to channel the water, but if it isn’t, then you may need to seek professional help. Below are some tips and tricks for installing a successful land drain system:
Prevent sediment from entering the pipe
When installing your land drain, make sure that you choose one or two techniques for preventing the entry of soil into the pipe. This will trigger a buildup of sediment in both the pipe and soakaway. Utilize a catch-pit or a non-woven geotextile around 10 millimeters above the top of your land drain.
Pick an appropriate soakaway crate
Select the right soakaway crate for connecting your land drain pipe to that soakaway system. Get a robust and strong soakaway crate that’s fabricated with plastic. Conventional, old-school crates might not be primed to withstand a constant flow of water.
Carefully plan the layout of your land drain system to make sure that the region you’re trying to drain isn’t further than 2.5 meters away from the land drain’s location below the ground. For larger spaces, a 10-meter radius is recommended since a 2.5-meter radius could, in theory, quadruple the cost.
Test the soil’s permeability
Testing the soil’s permeability as well as sustainability for the drainage system involves digging holes, taking samples, and determining the rate of water inflow into that particular hole. You can choose to perform this procedure on your own or hire a contractor to help you select the right drainage system.
During winter or early spring, the soil profile often tends to be saturated. So, dig holes that feature a depth of between 1.0 to 1.5 meters. Preferably utilize a hand auger featuring a post-hole size diameter of between 75 and 150 millimeters. Before digging, make sure that the surface water is channeled away from the hole so as to avoid confusing the observations.
Utilise a sensible gradient
When it comes to land drain pipes, the recommended gradient is 1 in 150. And it shouldn’t, therefore, be anything more than 1 in 100 since the water will flow extremely fast and too aggressive. Plus, you should only use industrial gutters to boost efficiency and reliability.
Is your land waterlogged because of excess rainfall or impermeable soil? Don’t worry. Installing an effective land drain system can go a long way in fixing the problem and restoring your land’s condition to normalcy. The above guidelines will help you make an informed decision regarding the purchase and installation of the perfect land drainage system.