How to Thaw Freezing Underground Sewage Lines [Easy Steps]


fixes and repairs

Freezing is an amazing way to preserve food, because the bacteria that cause food spoilage are completely harmless below freezing temperature. Which is why you have a fridge or a deep freeze sitting somewhere in your kitchen or living room doing just that for you.

But, that is not always the case when cold chilling winds attack your plumbing lines especially the long lengths running from your house to your septic tank. The septic tank is more like a house under the ground with holes that allow waste products from your home into it for storage, with the possible functionality of ferrying them away too.

sewage system

While septic tanks and drain-fields solve the problem of decomposing effluents from your house, they could easily be affected too when they are clogged. One common problem is the issue of freezing septic lines.

The issue of freezing pipes is as old as the introduction of pipes as a means of transporting liquid material from one place to another.

When septic tanks collapse due to freezing lines, this could cause a major blow up. Getting a fix done could drain a chunk of your savings especially if it is serious.

When a septic pipeline, including the entire system freezes, it causes a back-flow of wastewater. Instead of going downstream, they return back, pushing back up due to pressure and finally causing a mess in your sinks, bathrooms, anywhere there is an outlet or inlet.

Why Do Freezing Systems Occur?

Freezing septic system and pipelines are commonplace where cold weathers are rampant. If you are wondering whether the plumbing lines leading to your septic tank is frozen, here are few indicators that may hint so.

  • If your toilet cannot flush.
  • If the drains in your house are struggling to function or have just stopped.

Typically when this occurs during winter periods or colder periods, it could be due to a leaking fixture or joint that has been badly fractured following attacks from the harsh temperature condition. Other times it could be caused by staying away from your home for too long.

Adequate temperature is needed to keep your septic system functioning enough to decompose wastewater. When this happens, your pipes and septic system risk getting frozen. And then, you have wastewater seeping out from the ground ruining your home, smelly things sprawling all over your yard. And worse a burst or break could happen.

How to Thaw Your Septic Pipe

Frozen septic lines and other plumbing lines can cause great problems if ignored or not discovered on time for homeowners like you. Nobody enjoys incurring costs on damages. They sting to the heart. However, when things like this occur, it is important immediate attention is given to it preventing it from ballooning into a very terrible and ugly crisis.

There are different ways of thawing a septic pipe. It important this is done carefully. Any complications could lead to further damages and more money to splash on expenses. This is why plumbing experts are usually recommended for the jobs, unless you are one of them.

This method can be applied if your pipes are hidden inside the tank, underground. It doesn’t work really well for all bends. Some of the tools you will need are: shovel, sump pump, bucket, tools for repairing and cutting pipes, a flexible tubing or hot water hose long enough to reach the pipes.

  • Locate your home’s septic tank/system. This is the central storage that houses your septic waste /wastewater. It shouldn’t be too far from your house. Start by looking for the nearest septic tank cover to your home. (this can be easily achieved with plumbing plan for your home or can reach your local plumber for help)
  • Septic tanks have concrete covers. When you locate yours, you need to find a way around it. Use a crowbar to pull, and eventually drag the concrete cover to reveal the tank. If the ground holding the tank is also frozen, you may need to use a shovel to dig around it.
  • Connect your flexible tubing or hot water garden hose to a hot water supply, preferably one that is not from your house source, like a utility room.
  • Before blowing hot water down the septic pipe, make sure the water is not more than 110 degrees Fahrenheit. If it is beyond that it you could burst the pipe.
  • Next, try locating the septic pipe that is running from your house to the tank. Once done, fix the nozzle into the pipe so that it is pointing towards your house when you release the hot water.
  • Flip the switch to turn on the hot water from your utility room. Drive the host down the septic line until you jam any kind of block in the pipe.
  • Spray hot water directly into the ice block that is stuck in the pipe. This will in turn melt the ice. Keep pushing down until you experience a free course.
  • Once down, and you have successfully cleared and thawed the block, pull out the hose away from the septic pipe.
  • Finally, rearrange the whole area, then clean and sterilize your entire hose.

If your septic pipes are visible enough then the following methods can be applied.

1. Use Hot Water

Kids know that when they are cold, cuddling up in foetus position can solve the problem of limited heat. Other times they could just sit, huddled round a fire, or wear thick clothes. Anything that would sustain their body heat or increase it. It essentially how it works for pipes to. To clear the clog or jam in your pipe, you need to thaw the ice. This means melting it. Only heat can do that. There are various ways of getting heat. One of such is: through hot water.

Once you locate the frozen septic pipe, grab yourself a bucket of hot water and a bowl. Pour the hot water on the pipe. When doing this, do it slowly and carefully. Most PVCs react to hot water quickly leading to excessive expansion. If there is ice in that section, you could end up having a crack or a tear on that area, further worsening your problem. Hot water is a good option for heating the frost pipes. However, make sure it isn’t too hot, as you risk sinking into further problems.

2. Use a Heat Lamp or Electric Heater

If you are shying away from doing 1 above, another alternative is the use of a heat lamp or an electric heater. Both serve the same purpose. Just like burning wood in the cold, the surrounding air turns warm, giving heat to those who are only close to it. The Electric heater or heat lamp performs similar functions. However, for this method you need to know exactly where the frost has bitten your septic pipe. When you know exactly where, you can introduce the heat lamp or electric heater. A light source should be close by where you can plug in. Aim the electric heater or lamp at the septic pipe, the heat from the pipe will warm up the air, gradually thawing the ice on your pipe.

This method takes long but offers excellent results.

3. Use a Heat Gun

If waiting long hours using the heat lamp isn’t a thing for you, then you can opt for a heat gun.

Heat needs to be evenly spread along the pipe to thaw the frost. Move your heat gun back and forth to distribute the heat from the gun around the septic pipe. Take great care not to bring it too close to the pipe. You could risk bursting the pipe. Can’t get a heat gun, a hair dryer will do.

4. Use Electric Heat Tape

Electric heat tapes or wires are not just a good remedy for frozen drain lines indoor; they can also be used for thawing your septic pipes outdoor too.

This method is fine if the frost has affected a large area of your septic pipe. Wind the tape on the peptic pipe. Connect one end of the heat tape to a 110 volts outlet. While this process is effective, it is not really efficient. You may have to wait for longer hours. However, one great benefit of using the heat tapes is: it unfreezes your pipe gradually, keeping them from further freezing.

5. Use a Pipe Thawing Machine

Pipe thawing machines may be expensive in your area and could hurt your budget. Renting one from your local store is the ideal option here if you are trimming down your expenses. Wheel the thawing machine (if it has tires) or carry it if it has none using the holder to the location where the septic pipe is frozen. Connect the pipes to the clamps of the thawing machine.

Take note, the pipe should be in the middle section of the clamps. Make sure the pipe connections are secure and tight to avoid overheating at the clamps. Connect the power cord to an 115V power supply. Sit out, and watch the thawing operation until you are satisfied. Then, unplug your thawing machine and take off the clamps off the thawed pipes.

Any of these methods above should be able to remedy the situation. However, a ounce of prevention is better than a pound of cure. Avoiding or preventing your septic pipes from freezing in the first place is the best method there is here. A good follow-up on the conditions of your septic pipes during cold winter months will definitely prevent your pipes from taking a hit, and eventually getting clogged, which in turn affects your entire septic system.

How to Prevent Frost in Septic Pipes

The first step to stop a looming disaster, especially one you know the odds of it happening is very likely,  is by preventing it.

A septic system will fail if issues like a frozen septic pipe become a spin. However, you can prevent this by doing any of the following.

Apply Mulch and Snow Cover

Applying mulch and snow can act as an insulating layer protecting both your pipes and septic system from freezing. Doing this creates heat around the soil area since these pipes are basically laid outside your home. They’ll prevent frost from creeping deep into the ground and affecting your septic pipes and tank system.

Snow however, must not be compacted or hard-pressed by avoiding putting snow covers where there are too much traffic. This prevents the spread of air which is needed to generate heat.

Make Quick Fixes to Leaks and Drainage Issues

Neglecting a leaking fixture or a broken drain line could inflate the problem of your septic system. You don’t want wastewater that should have been buried underground welling up to the surface of your yard and creating a huge mess.

Ensure damaged septic pipes are quickly replaced. If you notice a strain on your septic pipe and a bulge that looks like it could burst anytime, get it replaced quickly before leaving town and going for a holiday.

Bad Ideas for Thawing Septic Pipes

Septic pipes transport wastewater and other toilet materials into your septic tank where further decomposition takes place. But, they can get clogged up for a number of reasons. A common phenomenon is freezing during winter months. When this happens it could put a strain on wastewater collected from your toilet, bathroom and kitchen. Back-flows are likely to happen. Toilets won’t flush, waters from sinks are driven all the way back to the home etc.

This is dangerous. And if not addressed quickly could turn into a bigger mess. The prevention tips we have given are to ensure you don’t encounter any problems with your draining lines. But, if you notice any of the warning signs, then we suggest you check your septic area to map out the area that has been affected by the cold.

The Do-It-Yourself approach is a guide to help you thaw the septic pipes if you prefer that approach. However, when doing it by yourself, you need to do it with great caution. You put not just yourself but your property at risk when you go doing it all wrong. This will invite extra costs because you may need to hire a plumbing expert to evaluate the nature of damage and proffer solutions for you.

Most times it is easier to hire a professional to do the job for you, just to be on the other side of the line that’s safe.

That said, there are a few things you should never try if you feel the freezing damage has not only dealt a devastating blow to your septic pipes, but also to your septic tank. If this is the case, below are things you shouldn’t do before alert your local plumber.

  • Never attempt to add any form of antifreeze, salt or additives.
  • Never attempt starting a fire on the ground above where the tank has been buried.
  • Do not attempt to leave your faucets or taps running continuously in a bid to thaw the pipes. This could put more pressure on the frozen pipe and eventually cause it to burst open.

Joe Taylor

Over 2 decades of remodeling experience, Joe is an expert in home improvement. He is now the Managing Editor of PlumbJoe where he writes guides for homeowners. His hobbies include climbing, running and playing the piano.

Recent Posts