Water in leach field vent pipe

Septic Drain Fields / STAs / Leach Fields

Septic Drain fields, also most commonly called Soil Treatment Areas (STA), or the old term Leach Field, are subsurface wastewater disposal systems used to remove contaminants and impurities from the liquid discharged by a septic system.

There are several different types of STA’s in use today. The most commonly used is a series of four-inch diameter Perforated PVC pipe encased in two-to-three foot wide stone filled trenches, with porous material (like gravel or sand) around and underneath the pipe to promote drainage and reduces root growth near the pipeline. A minimum topsoil placement is covered over the porous material to protect contact with wastewater and reduce infiltration from rain and snow.

Cut-away of Septic Drain field/Leach Field

Cross Section of Septic Drain field/leach Field

Having problems with your STA/leach field?

Symptoms of trouble:

toilets won’t flush, or flush slowly
wetness on top of the leach field (Example pictured here)
water standing in inspection or vent pipe from leach field
water or sewage backing up in the house

Wetness on top of leach field

How do you know if it is a STA/leach field problem or a drainage problem?

You can call your septic company (Us: 303-526-5370!) or if you are able and handy, check the level of liquid in your tank.

Using your favorite shovel, pry up the tank lid or lids. The level of the tank should be down where the inlet comes in from the house or on the outlet where the effluent leaves the tank for the leach field. This is about 10–12 inches down from the top of the tank. If the level is normal, (at the bottom of the inlet pipe), you have a clogged line from the house to the tank. Call us for recommendations if plumbing service is needed!! 303-526-5370

If this level is up to the lid, or overflowing you have an obstructed line to the leach field or a problem with the drainage in the leach field.

Problems with leach fields are a result of many different reasons.

Age of leach field
Engineering or installation problems
Not pumping tank often enough
Compaction problems from parking cars, livestock on top of leach field lateral lines
Spring runoff of water can flood leach fields.
Too much water usage. Hydraulically overloading the system. This causes a bio mat to build up in the leach field and the bio mat starts restricting the water absorption in the leach field

If you are on a septic system and your leach field is not draining the way it should, you can replace the leach field if you have room on your property or we have some alternatives listed below.

Leach Field Replacement Alternatives

TERRALIFT

We have a Terralift machine. We use this over the leach field surface. The machine punches a probe down in the ground 6 ft, then a compressor injects air and polystyrene beads. This fractures the ground and the beads opening up paths for the water to leach back in to the ground. We have had good results with this process. Call us to schedule an appointment to come out for an evaluation. Also check out the Terralift on www.terraliftinternational.com.

BIO-REMEDIATION

Bio-remediation is another possible successful solution. It is a specially formulated bacteria we use on a problem field. Once injected in the system, it goes after eating up the bio-mat that has accumulated. Find out more at www.propump.com or we can send you a booklet on the process. Just contact us.

GET UP TO 150$ OFF A SHOCK TREATMENT

The leach field, also referred to as a drain field, receives the wastewater from the septic tank. This section of the septic system consists of a network of perforated PVC drain pipes, crushed stone and a layer of unsaturated soil. Wastewater generally flows from the septic tank to the leaching bed by gravity. However, a pumping station can also be used to allow the wastewater to reach the leaching bed when conditions do not allow for the simple use of gravity. The wastewater then enters the leaching bed, flows through the crushed stones, and infiltrates into the receiving soil. This final filtration step involves bacteria and other microbes that further treat the wastewater before it reaches the water table. This natural purification principle prevents groundwater contamination. However, it sometimes clogs up. Learn how to unclog your leach field in this article!

How is a leach field made?

The leaching bed plays a crucial role in the wastewater treatment system and if it fails to function properly, the entire system will be affected. It is therefore important to avoid structural problems in the first place by ensuring that it is properly constructed. This is why only properly licensed contractors can carry out such a project. But first and foremost, you will need to perform a percolation test and a thorough evaluation by an engineer. The percolation rate measures the time it will take for water to percolate down 1 inch in a hole that has had water poured into it so that it is completely saturated. Sandy soils have a fast percolation rate while clay soils have a slow percolation rate. For example, the percolation rate in sandy soils may be 3 minutes while the percolation rate in clay soils may be 48 minutes. A good soil should not have a percolation rate that is too high or too low. If the water sinks one inch in less than 5 minutes in the hole, it is an indicator that the effluent will seep out too quickly to be properly treated. On the other hand, if it takes more than an hour for the water to settle, the effluent is not infiltrating fast enough and this can lead to backflow problems. The engineer will use the results of the percolation test and the layout of the various components of your property to recommend the type of system to use and how to install it.

Steps followed when building a leach field

Once all the tests have been completed and the construction plan is in hand, it is time to start digging the trenches. The number of trenches to be dug depends on the size of the septic tank and the amount of wastewater that will be discharged to the leaching field. Each trench should be of equal width (approximately 3-4 feet). In addition, the trenches should slope slightly downward.
After the trenches are dug, they should be filled with crushed stone. The bed of crushed stone should be at least 1 to 1 1/2 inches thick and spread throughout the trenches. This step is important because it allows for better drainage of the effluent under the perforated pipes.
The perforated pipes are then placed on the bed of crushed stone. The pipes are tied down to ensure that they are firmly connected – enough to prevent them from shifting or becoming misaligned over time.
The perforated pipes are then covered with more crushed stone. About 1 to 3 inches of crushed stone should do the trick…
A geotextile membrane is then added over the crushed stones. The membrane prevents soil or dirt from slipping between the crushed stones and blocking the leaching bed.
If not already done, add a drain line connecting the septic tank to the leach field pipes.
Finally, the trenches are filled with soil to level them and make the surface of the leach field more uniform. You can then add a layer of grass over this area. And avoid planting anything else in or near this area at all costs.

How long does a septic leach field last?

A well-maintained weeping bed should last at least 25 years, but it may be shorter or longer depending on a few factors. Most leaching fields fail due to biological or hydraulic overload. Hydraulic overload occurs when too much water is sent to the septic tank. For this reason, it is recommended that tasks such as laundry be spread out during the week instead of doing too much at once. This prevents hydraulic overload of the system. Biological overloading occurs when too much organic material reaches the leaching field. As a septic system owner, you must be very careful about what you discharge to the wastewater treatment system. The only solid waste that should go into your septic system is toilet paper and feces. In addition, we recommend the regular use of biological additives to increase the efficiency and longevity of the system. Bio-Sol’s Septi + can prevent biological overload in your system by maintaining a very active bacterial flora.

What is clogging your leach field?

Like the septic tank, the leaching bed cannot last forever. All leaching fields will eventually need to be replaced. However, with proper care and maintenance, your leaching bed should serve you well for decades. The leaching bed uses aerobic bacteria on the receiving soil to purify the wastewater before it reaches the groundwater. These bacteria break down organic matter and also help eliminate viruses and reduce nutrients in the wastewater. When your leaching bed is in good working order, the wastewater from your home is well treated before being returned to the water cycle. However, clogging in the leaching bed interferes with this process, resulting in inevitable environmental pollution. So, before look at how to unclog your leach field, let’s see what’s clogging it…

Biomat

As the wastewater flows through the leach field, a black, gelatinous layer develops under the distribution lines. This layer is actually a biomaterial sludge called “biomat”. Since the biomat is watertight, it greatly reduces the percolation of effluent into the soil. This biomat is usually composed of organic matter and anaerobic bacteria that attach to the soil and crushed stone. These bacteria feed on the organic material in the effluent. Biomat is not normally harmful to the system. On the contrary, it helps to further filter the wastewater by slowing down the infiltration rate and retaining the organic matter before the water enters the soil. However, an imbalance in the growth of biomat can cause serious problems. The more the black gelatinous sludge accumulates in the trenches, the more difficult it will be for the wastewater to infiltrate and then percolate into the soil. Even a small hydraulic surcharge can cause sewage backups and potentially spills. When sewage backs up, it will always flow to the location that offers the least resistance. This may be where the earth fill of the leaching field is, through the septic tank lids or even inside the house! When this happens, the goal should not be to completely eliminate the biomat. It is simply a matter of restoring the balance of this biological system by reducing the accumulation of organic matter in the trenches. Note that proper care and maintenance of the system will help prevent such an imbalance, which will save you a lot of trouble (like having to unclog your leach field).

How do you know if your leach field is failing?

The most obvious sign of a failing leaching bed is, of course, the overflow of wastewater to the surface. If the receiving soil in the leaching bed cannot accommodate any more water, the effluent will rise to the surface of the soil or, in some cases, flow out the end of the trenches. The main reason the effluent stops flowing is because too much biomat is being produced. Here are some signs to look for to see if you need to unclog your leach field…

Sluggish drains and toilets

Before the drain field stops working completely, you may notice that water is draining more slowly through the house. As long as there is room for water, the drains will continue to work. On the other hand, water may be draining more slowly. If you ignore this problem and it is caused by the leach field, the problem will get worse over time. The septic tank may become too full and the water may not be able to seep into the ground at all. Of course, there are other plumbing problems that can lead to slow drains, so we recommend you look for other signs as well…

Septic odors

Septic tank odors can be present near the leaching field or inside the house. It is another indicator that the leaching field is failing. This is probably one of the easiest signs to identify, as it is very unpleasant. If you smell that rotten egg smell, first make sure it’s not a buildup of organic material in the plumbing system. You can use an environmentally friendly drain cleaner (SeptiDrain) or check for abnormally high water levels in your septic tank. If the signs are accumulating, you can deduce that the leach field is most likely at fault.

Sewage backing up in the house

When water is returned to clogged septic fields, the water level in the septic tank tends to rise. If there is no space left in the septic tank, the wastewater will back up through the opening or into your home. If you notice an abnormally high water level in the septic tank, it is almost certain that your leach field is at fault. The water level should always be at the level of the drain line connecting the septic tank to the leaching field. If the water level is higher than the drain line, it means that the leaching field cannot hold any more water and it is backing up into the septic tank. It is then necessary to check if the soil may be saturated due to heavy rainfall or snowmelt and also to evaluate if there has been a recent hydraulic overload. This may explain a higher than normal water level. But, if the problem persists, we can deduce that the leaching bed is no longer functioning properly (it is most likely clogged).

Greener and taller grass around the drainfield

If you notice taller, greener grass where your leach field is located, it’s an indicator that your leach field is not functioning properly. If wastewater can no longer infiltrate the soil, pressure can cause it to rise to the surface. When this happens, the nutrients in the wastewater can make the grass grow faster and look greener.

Puddles of water in the yard

If you notice puddles on the field, it is possible that a hydraulic overload has caused the water to rise to the surface. With a clogged leach field, the pressure is causing the water to rise. When discharged in large quantities, wastewater can literally puddle on the ground. If this water smells like rotten eggs, be very careful not to touch it and keep your children away from the area. In some cases, perforated pipes in the leach field may become disconnected or break. If a heavy vehicle has driven by, this may be what is causing the sewage to back up. Otherwise, it is more likely to be caused by a clog.

Soil sinking or collapsing over the leachfield

If you notice that the soil is abnormally wet where the leaching bed is located, it is also an indication that the leaching bed is no longer functioning properly.

How to unclog your leach field?

You should attempt to repair your leaching bed as soon as you notice a problem with the system. Otherwise, the problem can get worse and cause wastewater overflows. These overflows are dangerous for you and the environment. Furthermore, it is forbidden to pollute the environment and the local authorities could force you to replace your septic system.

As previously discussed, the discharge of organic particles to the leaching bed promotes the production of biomat and creates an imbalance in the natural water filtration system. This is in addition to the grease that can sometimes find its way to the leaching bed. The result is a watertight biomaterial sludge and this sludge slows down the infiltration of wastewater into the receiving soil abnormally. Biomat is not the enemy of your septic system, but an imbalance in the microbial growth of this sludge can cause the leaching field to clog. Therefore, the accumulation of organic matter in the leaching field must be eliminated and the sludge layer that clogs the field must be reduced.

There are several solutions to try to solve this problem… But the fastest, simplest, safest and most ECONOMIC is without a doubt the one proposed by Bio-Sol!

Bio-Sol offers shock treatments designed to specifically treat organic matter accumulation problems. These shock treatments are 100% ecological (and therefore safe) and you can do them yourself. The products used for shock treatments contain bacteria and enzymes specifically selected to eliminate waste found in septic systems. The addition of a high concentration of these bacteria and enzymes is usually sufficient to break down the organic matter that has accumulated in the leaching bed and unclog your leach field. This reduces the amount of sludge in the field and allows the wastewater to infiltrate much more easily into the soil. And there you have it, your septic system is working again!

In some rare cases, a pipe in the leach field may have become disconnected or the drain line may have collapsed. This usually happens when a heavy vehicle drives by… Has this been the case recently? If so, then you should run a camera and inspect to make sure it is not a structural problem.

Otherwise, the septic system must be replaced…

How much does a new leach field cost?

If you choose to replace your leaching bed, you will most likely have to replace the entire septic system. You will need a new percolation test and an evaluation by a qualified engineer. If you can use a conventional septic system, it will cost you between $5,000 and $12,500. However, if you need to install an advanced system, the replacement will cost you much more (between$15,000 and $30,000).

Replacing a septic system is very expensive! That’s why we strongly encourage you to try to solve the problem first by opting for one of the proposed alternative solutions. Bio-Sol offers, once again, the fastest, simplest, safest and most economical solution.

PROMO TO HELP YOU UNCLOG YOUR LEACH FIELD : Get a discount on a shock treatment by accessing our monthly promotions page. Click here to save even more: SAVE UP TO 150$ ON A SHOCK TREATMENT

Conclusion

A clogged leach field will compromise the entire system. It can result in sewage backups in the house, septic odors, sewage leakage on the lawn, and contamination of groundwater. To avoid these and more problems related to leachfield failure, you should unclog your leachfield through shock treatment. Shock treatment is the introduction of billions of bacteria and enzymes into the septic system by adding biological additives. The idea is to allow bacteria to digest the organic waste at a faster rate thereby unclogging the system. Bio-Sol’s shock treatment product is made from bacteria and enzymes so it will give you a septic-safe remedy to unclog your leach field!

Can you clean field lines?

You can use a sewer jetter to clean perforated PVC septic leach field lines from 2" to 6" ID. A sewer jetter can help you scrub away sticky sludge and flush out dirty residue to help reduce the need for subsequent cleaning of the lines.

How do you unclog a septic tank outlet?

Sprinkle the drain with baking soda, then dump vinegar into the pipe. Leave the mixture to sit in the pipe for an hour or two. Finally, flush the drain with hot water. If the clog is small, this could be enough to clear the pipe.