Drainage & sewer systems, built to grade
JMP Group installs and repairs gravity sewer mains, pressure sewer systems, house drains and manholes throughout Brisbane, the Gold Coast and the Redlands. Every line is laid to the designed grade, tested, CCTV recorded and handed over with as-constructed detail for the authority and your project file.
Scope of work
New sewer, replacement drains and everything in between
Gravity sewer mains
Reticulation mains, junctions and property connections laid to design grade with laser or GPS set-out and recorded invert levels.
Manholes & access chambers
Precast and in-situ maintenance holes, benching, step irons and trafficable covers set flush to finished surface levels.
Pressure sewer systems
Pump station chambers, rising mains and boundary kits for low-lying sites and bayside lots where gravity fall runs out.
House & sanitary drains
New sanitary drainage, overflow relief gullies, inspection openings and re-routing around extensions or new structures.
CCTV & jetting
High-pressure jetting to clear the line, then camera inspection with a report identifying defect type, depth and position.
Excavated repairs
Section replacement of collapsed, root-damaged or misaligned pipe, with reinstatement of driveways, paths and turf.
Diagnosis
Reading a blocked drain before opening the ground
The symptom rarely names the defect. This table maps what property owners report to what the camera usually finds underneath, and to the repair that follows.
| Symptom | Likely cause | Typical repair |
|---|---|---|
| Repeat blockages every few months | Root intrusion at a joint, or a partially collapsed section holding solids | Cut out and replace the affected length, remove the root source |
| Sewage surcharging at the overflow gully | Full blockage downstream, sometimes in the authority's main | Clear and camera the line, then determine which side of the boundary owns it |
| Slow drainage across every fixture | Insufficient grade, a sag in the line, or heavy scale build-up | Re-lay the section to correct fall and record new invert levels |
| Wet patch or subsidence in the yard | Cracked pipe leaking and washing out bedding material | Excavate the failure, replace pipe and bedding, compact and reinstate |
| Smell with no visible blockage | Broken inspection opening, dry trap or damaged vent | Locate and rectify the breach, then smoke or camera test to confirm |
General guidance drawn from our own field work. Each line is confirmed by camera before we quote a repair — no drain is diagnosed over the phone.
Boundary of responsibility
Whose pipe is it once it leaves the house?
In South East Queensland the property owner maintains the sanitary drain from the fixtures to the connection point at the authority's sewer. The main itself, and the connection branch within it, belongs to the water authority. Establishing which side a defect sits on decides who pays, and a camera inspection settles the question with evidence rather than opinion.
What the CCTV report gives you
- Footage of the defect with distance from the access point
- Surface-marked location and approximate depth of the failure
- Pipe material, diameter and condition of adjoining lengths
- A written scope you can hand to an insurer or body corporate
Questions
Sewer and drainage questions
What is the difference between a sewer main and a house drain?
The sewer main is the public asset that carries waste from many properties. The house drain, or sanitary drain, is the private line from a building's fixtures to the connection point on that main. Different owners, different licence requirements, different repair processes.
How long does a collapsed drain repair take?
A single excavated section repair is usually a one-day job once the line is located and approvals are in hand. Depth, rock, concrete surfaces and service crossings extend it, which is why the camera inspection comes first and the quote states the expected duration.
Can a drain be repaired without digging?
Relining suits long lengths of structurally sound pipe with cracks or root intrusion. A fully collapsed or badly deformed section needs excavation, because there is nothing left to line against. The footage determines which method applies.
When is pressure sewer used instead of gravity?
Pressure sewer is specified where a lot sits below the main, where fall across the site is too flat for gravity, or where the authority has designated a pressure scheme. Each property gets a pump chamber and a small rising main to the network.
Do you work on body corporate and commercial drainage?
Yes. Recurring blockages in unit complexes are investigated with jetting and camera work, then documented so the committee can approve a permanent repair rather than paying for the same clear-out each quarter.
Is council approval needed to alter a sanitary drain?
Notifiable and compliance-assessable plumbing work requires the appropriate approval before it starts and a certificate at completion. We identify which category the job falls into and lodge the paperwork as part of the scope.
Related work
Stormwater management
Pits, pipes, detention and lawful point of discharge.
Water supply systems
Mains, services, fire feeds and pressure testing.
Guides
Plain explanations of approvals, testing and repair options.
Report a problem
Describe what the drain is doing and we will tell you what to check first.