Disclosure: This post contains affiliate links, meaning we may earn money or products from the companies mentioned in this post if you purchase a product through one of our links. An example would be Amazon.
What Might Cause A Toilet To Gurgle On a Septic System
You may be a part of the 20% of Americans that rely on an on-site septic system to dispose of your sewage. In a properly functioning septic system, your drains clear wastewater at a speed of about one gallon every 30 seconds. The “silence” of the entire process is something we easily take for granted. That is until we experience what could be increasingly persistent gurgling sounds with every flush or draining of water.
You might notice that your toilet gives out a gurgling sound during flushing, or sometimes, at random times. The gurgling sounds are basically gas bubbles being released from collected water and this is a certain sign that there is a problem somewhere. Diagnosing the actual issue may take a bit of detective work, but gurgling sounds from your plumbing, definitely, should not be ignored.
Why is your toilet gurgling on a septic system? The simplest (and least worrisome) diagnosis is that the plumbing drain directly underneath your gurgling toilet, or within close proximity of it, is clogged. This causes slow drainage and gurgling in all fixtures connected to that drain. When a toilet gurgles, it is an indication that negative air pressure (suction) is building up in the drain line, creating an air-lock. This is often caused by non-septic-friendly items being flushed down the toilets (such as disposable diapers, sanitary pads, cigarette butts, and other non-biodegradable matter). A worse possibility is that your septic tank is full, preventing or interfering with the flow of greywater from the tank and into your drainfield. Here, we will discuss the details of what causes your toilet to gurgle and what you can do about it.
If a minor plumbing blockage is a culprit behind the gurgling sounds coming from your toilet, your drains may appear to otherwise be working properly. Although, you may be noticing a sluggishness in how quickly your sinks and toilets drain. This is especially noticeable on days when there are surges in water output (like laundry days or when you have additional guests). More often than not, these clogs require snaking or jetting to remove the blockages. A powerful product like SeptiFix can be flushed in your toilet and be used to break down clogs and waste in your septic tank. Read our SeptiFix Review Here
The first thing to do, if you wish to investigate where the gurgling is coming from, is to seal off the drains in nearby sinks, showers, and tubs and then use a plunger on your toilet. If the cause of the gurgling is in the drainpipe, simply using a plunger on the toilet could create sufficient pressure to dislodge a light-to-moderate blockage. Bathroom fixtures (bathtubs, sinks, showers) typically connect to the same drain line (or the line that runs from the toilet) this is why, before plunging, you’ll want to seal off these other drains. Duct tape will do. If you plunge without sealing these other drains, the pressure from the plunging can escape through these other drain fixtures, instead of dislodging a blockage. With the toilet bowl full of water, fit the head of the plunger tightly to the drain hole in the base of the bowl. Try to dislodge the clog with 10 to 15 firm pumping motions. Then wait to see if the toilet gurgles again. If so, you will certainly need to investigate further into your septic system.
How to Fix a Gurgling Toilet
As one of the most-utilized fixture in the house, a fully-functioning toilet should be a top priority. Fortunately, you can diagnose the cause of bubbling and gurgling sounds coming from a toilet (as there are several possible causes), but if the longer you leave it unresolved, the problem could get worse. Such sounds can come from the water line or the toilet itself, depending on the actual cause. As you undertake to fix one or several of such toilet problems, expect to need locking jaw pliers or vice grips, a wrench, and a screwdriver, at the least.
A clogged toilet bubbles and gurgles when it flushes. The easiest way to fix a clog is to use a plunger. The pumping action creates suction through the toilet trap that moves the blockage up and down to loosen it. Sometimes the force is enough to remove the clog. It is also possible that the vent is clogged from backed-up sewer solids. In this case, use a plumber’s snake to access the blockage through the toilet vent up on your roof. Plumber’s snakes are available at your local hardware or home improvement store. You could also rent a powered model from a home rental yard.
The air within the plumbing lines cause sounds in the toilet as it fills. The air causes the water fill line to spurt and spit, resulting in bubbling and gurgling in the toilet. To remove air from your water lines, turn on all the faucets in the house until the water starts flowing smoothly. Allow the water to run until the spitting and spurting subsides, and then shut all the faucets off. If the problem persists in your water lines, inspect for a plumbing leak elsewhere in the facility.
The build-up of sediment in the toilet tank due to iron, calcium or magnesium in your water can cause the tank’s equipment or water lines to get clogged. If hard water scale forms at inlets to the tank, this could cause the water to spurt, gurgle, and bubble as the tank is filling up. If you notice a red-orange fur-like formation on the inside of your toilet tank, replace water inlet lines from the facility to the tank. You may use a scrub brush and a little amount of bleach to break down the iron bacteria buildup in your toilet tank.
If in spite of these DIY remedies, the gurgling persists, you are best advised to call on your trusted septic service provider for assistance. It is possible that the problem lies further into your septic system.
Why a Full Septic Tank Causes Gurgling in Your Plumbing
The most common reason for gurgling toilets and drains operating on an on-site septic system is that it, at the very least, is due for routine servicing. A full septic tank deters your septic system from properly functioning by interfering with the flow of greywater from the tank and into the drainfield. A full septic tank will not drain properly because sewer lines are blocked and wastewater is unable to flow out as it should. An over-full septic tank may eventually lead to catastrophic septic system failure, including ruining your drainfield and causing sewage to back up through the plumbing and into your home or building.
A septic tank, if left un-pumped for a long period of time, fills up with septic sludge and/or septic scum. The wastewater that comes from your home or facility carries with it solid waste matter. The heavier solids sink down to the bottom and form the sludge layer. Meanwhile, lighter solids (such as fat, oil, and grease) float to the top, forming the scum layer. What’s left is a relatively clearer middle layer of liquid, called effluent, and this fluid is what should leave the tank and travel to the drainfield. The excessive accumulation of sludge and scum will leave little room for effluent, eventually causing it to leave the septic tank prematurely.
That is, with more solid waste matter content, as it had less time to separate. This results in a build-up of solid waste matter ending up in your drainfield. This is where the “catastrophic septic system failure” earlier described begins. Scum and sludge in your drainfield will clog your soil, leading to sewage back-ups and pooling in your property’s surface.
There are four major factors that affect the rate at which your septic tank fills up:
- Septic tank size
- The number of occupants in the home or building
- Water usage
- The volume of solid wastes in the wastewater
A skilled and licensed septic inspection professional should be able to determine whether or not your tank needs to be pumped. Also, by analyzing all of these factors specific to your property, your contractor should be able to tell you the frequency of regular pumping that your septic tank will require.
Troubleshooting Septic Tank Problems
Let’s now take a more detailed look at the three most common septic tank issues and the best way to manage them.
Sludge build-up. The buildup of sludge in your septic tank is almost always the result of poor maintenance practices. It is vital that everyone in the household or facility watch what has flushed down toilets; it can be incredibly easy for solid waste matter to accumulate in a septic tank to the point where it can no longer hold anything else. In order to best avoid the need for septic tank repair, the septic tank should be inspected and pumped-out by a septic service professional on a regular schedule – typically every three to five years.
Broken drain lines or broken septic tank baffle. Broken lines require the assistance of licensed septic professional with the right equipment. They’ll need to perform a video inspection to locate and confirm the damage, whether it lies in drain lines or other components. Broken septic tank baffles (usually as a result of sulfuric acid or rust build-up) are an early sign that your concrete or steel septic tank is failing. Consider having the entire tank replaced with a more modern fiberglass septic tank. The good news is, your drainfield may still be fine.
Tree root pervasion. Tree roots are particularly drawn towards the area of septic fields and tanks and they can cause curtailed functionality or even complete breakdown. This is why it is important to maintain a distance clearing between trees or large shrubs and your septic areas. Simply cutting off the invading roots won’t work as these will simply recover. Your best bet is to hire a septic professional who understands how to treat the problem in the most effective way. Additionally, since roots in drain fields are treated differently, they’ll have the knowledge and experience to handle the problem permanently.
Fortunately, if you observe proper and regular septic system maintenance practices, it is relatively simple to prevent these disastrous and costly events from ever happening. If you follow a periodic schedule for septic service and inspection, you greatly reduce the odds of having to deal with a flooded (and foul-smelling) yard, overflowing toilets, backed-up drains, etc. Remember, the more you can avoid septic tank repairs, the better! If despite your best DIY efforts, your toilet gurgling persists, it is best to call in the professionals. Professional plumbers or septic system contractors are skilled, not to mention have specialized equipment, such as mini-cameras that drop in to vent stacks and powerful sewer augers that can chop right through tree roots. There’s also a slight possibility that the main sewer line in your property has come broken or has collapsed, requiring excavation and professional repairs. Though, we cannot say this enough: It is always better to prevent the repairs with best maintenance practices.