How much does it cost to unclog main sewer line?

Reviewed by Cristina Miguelez remodeling expert. Written by Fixr.com.

Clogs and subsequent back-ups occur when items get flushed that are not kind to a sewer system, like oil, grease, and paper products that are not septic-safe. It may also occur due to encroaching tree roots, depending on where the line is located. Having a main sewer line clogged is not uncommon, but it can cause other problems and, if not addressed properly, expensive repair and cleanup costs.

The national average cost to unclog a main sewer line is between $350 and $650, with most people paying around $475 to clean a mid-sized clog by hydro jetting the main sewer pipe between a house and municipal main line. At the low end of the spectrum, however, you can have a plumber come to your house and clear the clog using chemicals for $75. At the high end, you can pay up to $2,750 to replace a 10-foot section of a main sewer line with an unrepairable clog.

Cost To Unclog Main Sewer Line

Unclogging Main Sewer Line Cost by Method

Repairing a clogged sewer line ranges between $75 and $600, depending on the method. Whenever you’re experiencing an issue with your main line, the professional will probably have a few solutions to unclog it. This involves the plumber using a different unclogging method, which is the main factor that determines the cost. Below is a table with the most common methods used and the cost to unclog a main sewer line by using each of them.

Chemicals

If you opt to use chemicals to unclog a sewer line, you can expect to spend anywhere between $75 and $300. Chemical cleaners are typically used to unclog drains as they are more effective for them, but they can also be used for main sewer lines. They unclog pipes of the grease and debris buildup and roots, but they are not always as effective as hydro jetting. In fact, chemicals are mostly used for maintenance or after jetting or rodding to ensure the pipes stay cleaner for longer.

Snake Main Sewer Line

The cost to snake a main sewer line is $100 to $500, depending on if you will use a regular snake or an auger. This is the most common and cheapest unclogging method that involves inserting a coiled metal auger and pushing away any buildup down the plumbing system. The terms snake and auger are used interchangeably as both methods are the same, with the only difference being that the auger has a thicker wire used to clear large clogs. A snake is used for kitchen and bath drain clogs. Snaking is very efficient for small and mid-size clogs, but it’s not the best option for major clogs and won’t detect the cause of the clog or any underlying problems with the sewer pipes.

Rodding

Rodding is an option similar to snaking, which addresses any size pipe and is strong enough to remove roots. You can expect to pay $150 to $600 for rodding to remove the clog in a sewer line. Rodding involves using flexible rods of different sizes to push hard to move clogs and break them up so the water in the pipe can move freely again. Rodding is preferred over snaking for larger pipes because you can clear a wider area using bigger rods. Even though the rods are flexible, they are highly durable and strong, making it easier for them to break apart roots in their way.

Hydro Jetting Main Sewer Line

Sometimes, the plumber may decide to use hydro jetting to clear the clog, which costs between $350 and $600. Also known as main line jetting and water jetting, this method involves using a high-pressure hose with a special nozzle to shoot a powerful jet of water to push any buildup away from the pipes and unclog them. The nozzle comes in three different styles: penetrators, spinning rotary, and chain flail. Hydro jetting is effective and clears away more debris and residue than other methods. However, since it uses powerful water pressure, it can damage old pipes and cause leakage.

Replace Main Sewer Line

Sometimes, the clog can be so severe that a portion of the sewer line may need to be replaced. The main sewer line replacement cost can be anywhere between $50 and $250 per linear foot. The varying cost is because of the fact there are different types of replacement. For instance, the trenchless sewer line replacement cost is the most common cost homeowners pay because of the frequency of the method, so it may cost less than cast iron sewer pipe replacement. The price goes up if there are difficulties accessing the main line, such as the need to dig up concrete slabs. In this instance, be prepared to spend around $150 per hour for labor and equipment to excavate your home’s slab to access the line.

Cost to Unclog Main Sewer Line by Problem

The main sewer line clog repair cost depends on the problem to be addressed. Often tree roots grow through the lines bringing in dirt and debris and leading to clogs. In some cases, there can be more damage to the line, such as sagging and breaks. When this occurs, part of the repairs involves replacing the damaged parts. Below you will see the average cost, including labor, that you might expect to spend when having a main sewer line fixed.

Remove Tree Roots From Sewer Line

Removing tree roots that may be causing a clog in the sewer line costs $100 to $600 depending on the size of the tree and the extent of the damage, plus the cost of the replacement of the pipe if required. Tree roots can pose an obstacle when unclogging the main line. If you have trees near your main sewer line, its roots may break the outer protection and start growing into the pipelines. Over time, the roots block the line, and other dust and debris get stuck in the roots and cause a clog. Because of the nature of the clog caused by tree roots, the professional can rarely remove them and clear the clog without having to replace the pipes completely. The most important thing in these cases is hiring a professional who will do the job properly and ensure the sewer line will keep functioning to the best of its ability.

Belly in Sewer Line

Bellied or sagging pipes have to be replaced, which costs between $1,500 and $3,000 depending on the size of the pipe that needs replacement. When the soil or ground around the pipe softens, the pipes start pressing into them and sag, which creates a negative slope (a belly) in the pipeline. This belly disrupts the normal flow of water and collects water, debris, and sediment, which accumulates and clogs the pipes.

Broken Sewer Line

The cost to unclog a sewer because of a broken sewer line is $1,500 to $3,000, as the part that is broken requires replacement. If the lines and system are older, they could be made with clay or cast iron, which deteriorates over the years and eventually cracks. This causes problems in your plumbing, such as a breakdown of the pipeline and a back up of everything that goes down your drains.

Cost of Plumber to Unclog Main Sewer Line

The cost to fix a clogged main sewer line is $475. About $400 of this is labor costs, while the remaining is attributed to the materials the plumber will use. In most cases, plumbers charge a fixed rate depending on the severity of the clog, the location of the line, the urgency of the project, and the time it takes to unclog it. When this is an hourly project, plumbers charge an hourly rate of $45 to $200, with the whole process taking one to four hours. Urgent jobs and more severe clogs take a lot longer and cost more to complete.

If your plumber finds that sections of the line need to be replaced, you can expect to pay $30 to $150 per linear foot for labor, depending on the location and size of the pipeline. For materials, you will pay between $50 and $250 per linear foot.

If this is an emergency and you need to contact a contractor during off-hours, you will pay more to unclog the line. Emergency charges during non-business hours range from $50 to $100. When calling a plumber in the evening or on weekends or holidays, there is a premium of $45 to $200 added to the normal hourly rate.

Main Sewer Line Camera Inspection Cost

If the clog is more severe, or your contractor is unsure of the cause, they may do a video inspection for an additional cost of $100 to $800. However, the cost can be up to $1,500 when inspecting the entire sewer line system of your home. To perform this kind of inspection, the technician places a small camera on the end of the auger and runs it through the sewer pipe to detect the exact location of the clog or assess the risk of your pipes getting clogged in the future.

The sewer scope inspection shows the source of the clog, such as tree roots encroaching in the line. In this instance, the pipe will need to be dug up, the roots removed, and any damaged pipes will need to be replaced. It can take as little as an hour to identify and resolve the issue, or in worst-case scenarios, you could have plumbing contractors working on digging up a sewer line for several days.

Clog Causes

Some causes of an issue with the main sewer line cannot be helped, such as tree roots that find their way into your pipes and block the system. Other causes can be easily prevented. For instance, people often flush and rinse things they shouldn’t down the home’s drains, like thick paper, sanitary products, grease, food debris, or oil. Common toilet clogs are typically isolated to the single flush. On the other hand, sewer line issues impact all of the drains and fixtures in the house.

Another cause of frequent clogs is the age of the home and the plumbing installation. If the sewer lines and system are older, they could be made with clay or cast iron, which deteriorates and eventually cracks. This also causes problems, including a breakdown of the line and backing up of everything that goes down your drains, which would later have to be repaired.

Signs of a Clogged Main Sewer Line

It may be tough to tell if you have a stubborn, clogged drain or if the main sewer line is blocked. Typically, if you notice backflow from the tub or your sink, you probably have a clog or a blockage. If you hear strange gurgling sounds coming from the toilet, it may point toward a clogged sewer main. Also, when water bubbles come out of the shower or in the tub when you run your dishwasher or washing machine, you may have a clogged sewer main. If more than one sink or fixture is not draining properly or you are experiencing standing water in multiple areas, you likely have a clog in your sewer line or a broken pipe.

If the water backing up is coming out of a cleanout pipe, you are likely facing a serious type of blockage. Suppose this occurs with septic tanks, and the backed up water coming out is raw sewage. In that case, the issue needs to be addressed immediately by a professional because raw sewage contains a host of parasites, mold, bacteria, viruses, and chemicals that can be detrimental to your health.

Some other things to look for include foliage. If you see pieces of foliage or debris in the toilet when flushing or when it backs up, you could have an issue with your sewer line and tree roots. Call a plumbing contractor immediately if you notice this. Keep an eye out for water backing up in the shower when you flush the toilet or for sewage coming into any sink or tub in the house, as these are indicative of a main sewer line issue.

Also, don’t overlook a foul smell as this is one of the most common main line clog symptoms. If you notice odd soggy patches or indents on the ground, these signs all point to a problem with the sewer line. They must be taken seriously before they escalate into a bigger issue. If you’re unsure whether the signs indicate a clog, it’s always a good idea to call a professional to come and inspect the sewer line.

Factors That Affect the Cost of Unclogging the Main Sewer Line

The main factors that affect the clogged sewer line repair cost are accessibility, the severity of the clog, and the problem causing the clog. Some older homes don’t have a sewer cleanout, so the sewer lines are harder to access. Others have multiple turns and connection points that may make them harder to clean. The second factor, the severity of the clog, is pretty straightforward. The bigger the clog, the more time and effort it takes to clean the sewer, so the cost increases accordingly. When it comes to the type of problem causing the clog, you will pay more for harder to remove materials, such as roots.

The location and accessibility of the clog are cost factors that play a role in how long your plumber spends on the job. The price goes up if there are difficulties accessing the main line, such as the need to dig up concrete slabs. In this instance, be prepared to spend around $150 per hour for labor and equipment to excavate your home’s slab to access the line.

Roto Rooter Main Sewer Line Cost

A popular method of unclogging is using a roto rooter, which costs homeowners between $200 and $450 on average. A roto rooter is a large root-cutting machine wheeled into your sewer line as close to it as possible. Then, a technician will open up the sewer trap and insert an auger with a rotating cutting head down the sewer line. The curing head cuts everything, including small and mid-sized tree roots, and sends it down the sewer line.

Roto Rooter is also the name of the company that offers plumbing, drain, and water cleanup services to residential and commercial customers. The exact cost of the roto rooter services depends on what you use and where you are located. They provide services in most cities across the U.S. and Canada and typically charge a flat rate that doesn’t change regardless of the time spent on unclogging.

Maintenance

Homeowners can take some simple steps to prevent future clogs. First, make sure that every drain in the home is fitted with a trap to catch anything that should not be doing down. Also, avoid flushing oil, grease, and food debris down any sink, tub, or drain in the home. Keep a coffee can nearby to dispose of cooking fat, rather than risk pouring it down the sink or disposal. Make sure that you are using septic-safe toilet paper and never flush anything besides waste and toilet paper in your bathrooms.

Try to avoid using chemicals such as copper sulfate on your clogs as it is toxic and harsh to the environment. Typically, plumbers recommend having your main sewer line cleaned once every 18 to 22 months if your home is less than 40 years old. However, if your home is older, it comes with a higher risk for sewer and drain line blockages, so the frequency of cleaning should increase. Consider hiring annual cleanings. Sewer line cleaning costs are $150 to $600 from septic cleaning professionals.

Enhancement and Improvement Costs

Unclog Branch Drains

On average, you can expect to pay between $350 and $650 to clean out branch lines from your house, which is the same cost as clearing the clog in a main sewer line. The branch lines include the plumbing lines running from your home that connect to the main line. The process for clearing clogs in these lines is no different than with a main sewer line, with hydro jetting being the most common method for mild to moderate clogs.

Sewer Line Repair

Sewer pipe repair costs range between $50 and $250 per linear foot depending on the material of the pipe that is being repaired. The cheapest material to repair is a PVC pipe, while the most expensive one is a cast iron pipe. Similarly, the location of the crack affects the cost. Sewer lines that are easily accessible cost less to repair. Pipes located under the house cost more.

Sewer Cleanout

A sewer cleanout installation cost is typically around $600 to $2,000, although the cost may be higher depending on the location and installation difficulty. It’s mostly found in newer properties installed on the lawn or near the street, or sometimes even the roof vent. The term “cleanout” refers to a specific part of the system, not the process. It provides an easier way of accessing the in-ground sewer line to clear out any obstacles that older homes don’t provide.

Sewage Backup Cleanup

The cost to clean your home after a sewage backup may range anywhere between $2,000 and $10,000, depending on the extent of work needed. If your main sewage line gets clogged and starts leaking, the water that comes back to your home may carry hazardous elements that are dangerous for your health. When this happens, the first call should be to your local public works department. Your second call should be to your insurance carrier to ensure your home will be protected from any harm.

Septic Tank Cleaning

Septic tank cleaning costs from $400 to $1,000. Because the waste that comes back to your home carries bacteria, viruses, mold, parasites, and other harmful chemicals that pose serious health threats, this job should only be handled by a professional. They have the necessary equipment and knowledge to clean your septic tank without endangering anyone’s health.

Additional Considerations and Costs

• Permits. The average cost of a plumbing permit is $75, although the exact cost varies from state to state. There are many safety codes that you must adhere to when doing anything to a sewer line, which usually requires permits. Every project with sewer drains, inaccessible pipe replacements, new plumbing, water heater installations, and moving existing plumbing require a permit. This is because the sewer line impacts the health of you and your neighbors.
• DIY. There are always some tips to help prevent or unclog drains. DIY supplies run around $10 to $100. You can typically rent a sewer snake for the day for around $50. However, when it comes to an issue with a main sewer line, it really is most safe to rely on the professionals.
• Precautions. Unless you are advised otherwise, avoid flushing, using sinks, and filling tubs until the plumber arrives. It simply makes it easier and cleaner for the plumber to assess the situation.
• Tree root prevention. Annual chemical treatments can prevent roots from re-growing once you have repaired or replaced your line.
• Repercussions. Additionally, a blocked line can become an environmental hazard, subjecting you to fines and litigation in some instances.
• Responsibility. You may not be responsible for the clogged line at all if it’s located in the city’s sewer main. Typically, the city will send out a contractor with a camera to find the blockage and resolve it if it is on their end. If the clog is between your house and the city’s main line, however, the cost is yours to endure.
• Kitchen and bathroom drain clogs. If you notice that several fixtures and drains in your home are clogged at once, this may indicate a clog in the main sewer line. Typically, a clog in your kitchen sink or a clogged toilet at the same time are signs that you need to have it inspected.