A leach field, also termed a drain field, will eventually require repair or replacement as it ages and takes on effluent. A septic and aerobic expert can assist with either, so if your septic system is showing signs of impending failure, the first step is to schedule a professional inspection.
While inspecting your septic or aerobic system, a professional will consider the following factors:
- The cause of your leach field issues
- The age and apparent condition of your wastewater system
- The size and layout of your property
- Your budget and timeline
These factors will determine whether your leach field issues should be corrected with a repair or with a total system replacement.
Signs That a Leach Field Requires Repair or Replacement
Septic and aerobic systems both rely on a leach field to safely dispose of treated effluent. It’s connected to the system’s septic or treatment tank and is made up of several drain trenches. Each trench sits on a gravel bed, which promotes the ideal drainage rate and improves effluent quality further. Microbes in the surrounding soil also treat the effluent as it drains into the leach field.
If your drain field is having trouble keeping this process going, it may show the following signs:
- Reduced drain speeds inside – If your plumbing fixtures (sinks, baths, toilets) are draining slowly or backing up when they are not in use, this a major sign that your septic or aerobic system is draining slowly. If you hear gurgling sounds as water drains, this is also a troubling sign of system dysfunction.
- Water backing up onto the leach field or septic tank – If you know where your septic system and drain field are located, keep an eye on the area for any signs of septic system distress. One tell-tale sign of system failure is water pooling around the septic tank or leach field.
- Sewage odors – You may smell a problem before you see one with your septic system. If you detect sewage odors emanating from your leach field, it’s having trouble processing effluent properly.
- Overgrown vegetation near the drain field – Another problematic indicator for your leach field is an overabundance of vegetation growth. If grass is growing in thicker or if you notice unusually active plant growth, the ground may be receiving extra nutrients from inadequately processed effluent seeping out of the system.
If any of the above signs are present, schedule an inspection with a trusted septic or aerobic expert. The experts will be able to indicate whether your system is nearing failure or if repairs can be made.
The Most Common Causes of Leach Field Failure
The most common causes of leach field failure include:
- Bacterial overgrowth – As bacteria feeds on the effluent, it may experience an explosion in growth that overtakes the leach field and produces a clogged “biomat” or biomaterial layer that chokes off the field’s ability to drain wastewater.
- Oversaturated soil – If your soil has experienced a surge in runoff – via roof gutters, storm drains or another source – this may also overload the leach field and cause clogs to form in the system.
- Intrusive root growth – Trees and shrubs are capable of developing root systems that can intrude into the leach field and cause extensive damage. When roots infiltrate the leach field, replacement is more likely to be recommended as damage may be impossible to repair until the root systems are removed.
Benefits and Costs of Leach Field Repair vs. Replacement
While deciding between leach field repair vs. replacement will likely come down to what the septic expert determines you actually need, here is a quick breakdown of the benefits and a ballpark of costs regarding each:
- Process – There are a few ways to repair a leach field. One is to use high-pressure water to flush out any biological overgrowth and grease from the system’s drain structures. Another repair method is to divert effluent flows from one part of the leach field to another, allowing the oversaturated portion of the field to “rest.” A septic expert may also introduce additives – biological or chemical – to break down the biomat and free up any clogs.
During leach field replacement, the failed parts of the existing system (or the entire drain field itself) are extracted using heavy machinery. Once the existing system is safely decommissioned and removed, a new drain field is installed, often on a different part of the property. - Benefits – Leach field repairs are less expensive and generally less disruptive to the property. This is because any extraction work is confined to smaller areas and there is usually no need to prepare new areas of the property. Repairs will extend the drain field’s life by several years, depending on the age and condition of the field.
Leach field replacement is a larger-scale job, but it offers its own benefits. For one, a new leach field may last more than 20 years if properly maintained. If you’re replacing your leach field, you’ll have the option to upgrade or modify your existing design (such as installing larger pipes or additional drain trenches). Drain field replacement will uncover any hidden sources of damage (like subtle root structures) that may be missed during a repair. - Challenges – There are challenges associated with both processes. If you opt for leach field repair, keep in mind that repairs can’t resolve every problem, such as soil instability or overgrown roots. Further, while repairs will extend your system’s life, they are a temporary fix compared to drain field replacement.
The primary challenges with leach field replacement are cost and potential disruption to the property. As a comprehensive solution, drain field replacement will cost more than repairs and may require new site prep work on the property, depending on local ordinances. - Costs – The cost of leach field repair vs. replacement is highly variable and depends on where the property is located. In general, you can expect to pay anywhere from $1,000 to $5,000 to repair a leach field, depending on the nature of the damage and the required repair method. Replacing a drain field will run between $5,000 to $20,000 and up, depending on the size of the drain field and if your system will require additional components to run, like a distribution box.
Work with a Reputable Septic Company
When Repairing or Replacing a Leach Field
With on-time septic system maintenance, property owners should expect their leach field to provide roughly 20 years of reliable wastewater management. However, soil conditions, bacterial overgrowth or intrusive root systems will eventually cause issues. These issues can be mitigated with expert septic system repairs or replacement services, which will extend your system’s life and optimize its performance.
If you’re contending with drain field problems, or if your septic system just isn’t working as well as it used to, it’s time to bring in the professionals for a detailed septic system inspection. Once your drain field has been thoroughly checked out, your septic team can recommend the right approach – repair or replacement – and help restore your leach field’s efficiency and function.
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