How Do Plumbers Find the Cause of a Blocked Drain?

Clearing a blocked drain can restore water flow, but an important question remains: what caused the drain to become blocked in the first place?

Professional blocked drain diagnosis involves more than simply removing whatever is preventing water from flowing.

Depending on the symptoms and drainage system, a plumber may use CCTV drain cameras, specialised drain inspection equipment and high-pressure drain jetting to locate the blockage, clear the obstruction and inspect the condition of the pipework.

At Bright Water Plumbing & Gas, this approach allows us to investigate what’s happening inside a drainage system rather than relying solely on guesswork.

What Causes a Blocked Drain?

There isn’t one single cause of blocked drains.

Depending on the location and type of drainage system, a blockage may involve a build-up or obstruction within the pipe, while recurring drainage problems can sometimes indicate an issue with the pipework itself.

Potential causes can include:

Grease, fats and food waste
Hair and soap residue
Foreign objects
Tree-root intrusion
Sediment and debris
Damaged pipework
Displaced or damaged pipe joints
Restrictions within the drainage line

This is why identifying the underlying problem can be particularly important when a drain has blocked repeatedly.

How Does a Plumber Locate a Blocked Drain?

The investigation normally begins with the symptoms.

A plumber will consider where the drainage problem is occurring and how different fixtures are behaving.

For example, a single slow-draining fixture may indicate a more localised problem, whereas problems affecting several fixtures can suggest an obstruction elsewhere in the drainage system.

Specialist equipment can then be used where necessary to investigate further.

CCTV Drain Camera Inspection

One of the most useful tools for investigating drainage problems is a CCTV drain camera.

A specialised camera is fed through the drainage pipe while the plumber views the inside of the pipe on an inspection monitor.

This provides a real-time view of areas of the drainage system that would otherwise be hidden underground or behind walls and floors.

A CCTV drain inspection can help a plumber:

Locate an obstruction
Investigate the likely cause of a blockage
Check the internal condition of the pipe
Look for visible cracks or damage
Identify displaced joints
Identify some instances of tree-root intrusion
Check whether a blockage has been properly cleared
Record the inspection for future reference

The ability to actually see inside the drain can provide much more useful information than repeatedly clearing a blockage without investigating why it occurred.

Why Use a Drain Camera After Clearing a Blockage?

A drain camera isn’t necessarily used only before clearing a drain.

There can be significant value in inspecting the pipework after the blockage has been removed.

Once the obstruction is cleared, the camera has a clearer view through the drainage line. The plumber can then inspect the affected area and check for conditions that may have contributed to the problem.

For example, if a drain continues to block in the same location, an inspection may reveal an underlying pipe issue rather than simply another accumulation of waste.

If the pipework appears to be in good condition, that is useful information as well.

On a recent blocked drain job, our team used high-pressure drain jetting to clear the obstruction before carrying out and recording a CCTV camera inspection of the drainage system.

How Is High-Pressure Drain Jetting Used?

Where appropriate, Bright Water uses specialised high-pressure drain jetting equipment to clear blocked drains.

Drain jetting directs high-pressure water through the drainage line to break up and remove material causing or contributing to an obstruction.

The objective isn’t simply to create a small opening through the blockage. The equipment can be used to help clear material from the affected section of pipe and restore drainage.

The exact approach depends on the type and condition of the drainage system and the nature of the blockage.

Drain Jetting and CCTV Inspection Work Together

Drain jetting and CCTV inspection perform different jobs.

Drain jetting clears the obstruction.

CCTV inspection helps determine what’s happening inside the pipe.

Using the two technologies together can provide a much more complete approach to blocked drain problems.

A plumber can:

Locate → Clear → Inspect → Assess

This is particularly useful when dealing with recurring blockages or when there is reason to suspect a problem with the drainage pipe itself.

Can a Drain Camera Detect Pipe Damage?

A CCTV drain camera can identify many visible problems within accessible sections of drainage pipework.

Depending on the condition and accessibility of the drain, an inspection may reveal cracks, damaged sections, displaced joints, root intrusion, obstructions or other abnormalities.

However, a camera inspection is part of the diagnostic process rather than a guarantee that every possible defect will be visible.

The information gathered can help determine whether further investigation or repair is required.

What Happens if the Drain Is Damaged?

If an inspection identifies a problem with the drainage pipe, the next step depends on the type, location and severity of the damage.

Not every blockage means the pipe needs repairing.

This is another reason accurate diagnosis is useful. Rather than assuming a drain needs excavation or replacement, the plumber can first establish what is actually happening inside the system and recommend an appropriate course of action.

Why Do Some Drains Keep Blocking?

A drain that repeatedly blocks shouldn’t necessarily be treated as a series of unrelated incidents.

If essentially the same blockage keeps returning, there may be an underlying reason.

Recurring problems can sometimes be associated with:

Tree roots entering the drainage system
Damaged or deteriorated pipework
Pipe joint problems
Persistent build-up
Foreign material
Restrictions within the drainage line

A CCTV inspection can help determine whether there is a visible reason the blockage keeps returning.

Do All Blocked Drains Need a Camera Inspection?

Not necessarily.

Some straightforward drainage problems can be diagnosed and cleared without requiring a CCTV inspection.

However, a camera can be particularly valuable where the cause isn’t obvious, the blockage is difficult to locate, the problem keeps returning or the condition of the pipework needs to be checked.

Bright Water can determine which equipment is appropriate after assessing the drainage problem.

Blocked Drain Diagnosis Across Perth’s Northern Suburbs

Bright Water Plumbing & Gas is based in Quinns Rocks and provides professional blocked drain services throughout Perth’s northern suburbs.

Our priority areas include:

We also provide our plumbing services throughout the wider northern suburbs, so if your location isn’t listed above, contact us to check availability in your area.

Our plumbers have access to specialised drain jetting and CCTV drain inspection equipment, allowing us to both clear drainage problems and investigate what may be causing them.

Frequently Asked Questions

How do plumbers know where a drain is blocked?

Plumbers can use the symptoms of the drainage problem together with specialist equipment such as CCTV drain cameras to investigate the drainage system and help locate an obstruction.

Can a plumber see inside a blocked drain?

Yes. A specialist CCTV drain camera can be fed through accessible drainage pipework, allowing the plumber to view the inside of the drain on an inspection monitor.

Should a drain be camera inspected after jetting?

It can be useful. Once a blockage has been cleared, a camera inspection can help confirm the condition of the pipe and look for visible problems that may have contributed to the blockage.

Can CCTV drain cameras find tree roots?

A drain camera can identify visible root intrusion where the affected section of drainage pipe is accessible to the camera.

Can a drain camera identify a cracked pipe?

CCTV inspection can identify many visible cracks and other abnormalities within accessible sections of pipework, although not every defect will necessarily be visible from an internal camera inspection.

Why does my drain keep getting blocked?

Recurring blockages can have several causes, including persistent build-up, tree-root intrusion, damaged pipework, joint problems, foreign material or restrictions within the drainage system. An inspection can help determine whether an underlying issue is contributing to the problem.

How are blocked drains cleared?

The appropriate method depends on the blockage. Bright Water can use specialised high-pressure drain jetting equipment to break up and remove obstructions from drainage pipework where appropriate.

Need Help Finding the Cause of a Blocked Drain?

If a drain is blocked — particularly if the problem keeps coming back — simply restoring water flow may not tell you why it happened.

Bright Water Plumbing & Gas has specialised drain jetting and CCTV drain camera equipment to locate, clear and investigate blocked drains.

Our plumbers can inspect the drainage system, clear the obstruction and, where appropriate, check the pipework for visible damage or other issues that may be contributing to the problem.

For professional blocked drain services, contact Bright Water Plumbing & Gas on 0430 123 561.