Finding the best drainage contractors in Whanganui usually comes down to who can get under the ground quickly and tell you what is actually wrong. The firms below handle blocked sewer and stormwater lines, CCTV drain inspection, soak pits and new build drainlaying across the district, from yards in town out to Wanganui East, Putiki and Fordell. Action Drainage & Construction and Sharp Plumbing Services are among the Whanganui drainage contractors who take on both the diagnosis and the dig.
1Action Drainage & Construction
Action Drainage & Construction works across plumbing, drainage and siteworks from its Heads Road base, covering the wider Whanganui, Manawatū and Taranaki regions. Siteworks and drainage are a core part of the business, taking in stormwater, water and wastewater systems along with excavation and pipework for new builds. It suits both homeowners chasing a failing drain and commercial clients who need the whole drainage package on a construction site.
Services
- Sewer repairs
- Drain unblocking, including locating a blockage when its position is unknown
- New home drainage installations
- Repair of collapsed and broken drains
- Stormwater repairs and flooding or water infiltration work
Highlights
- Twenty four hour emergency callout on the same Whanganui landline
- Complete drainage package covering project management, excavation, pipework installation, controlled backfill and road reinstatement
- WorkSafe New Zealand certified for asbestos removal
- Siteworks capability including earthworks, site clearing, subgrade preparation and aggregate placement for building foundations and hardstands
Location & Contact
Name: Action Drainage & Construction
Address: 27 Heads Road, Whanganui
Phone: (06) 345 5891
Website: actiondrainage.co.nz
2Sharp Plumbing Services
Sharp Plumbing Services runs from an office and workshop on Moana Street in Wanganui East, and was founded in January 2014 by Rod Sharp and Charlotte Weber. Rod is a certifying plumber, gasfitter and drainlayer, and the drainage side of the business covers everything from laying new stormwater and wastewater lines to working out what is happening underground with a drain camera. It suits property owners dealing with surface flooding, a sodden lawn or a drain that keeps backing up.
Services
- Laying new stormwater and wastewater drains for new and existing homes
- Repairs to existing sewer, wastewater and stormwater pipes
- Stormwater separation to kerb connection, soak pits and rainwater detention tanks
- Groundwater drainage trench systems, surface water sumps and channel and grate solutions
- CCTV drain inspection and pipe locating
Highlights
- Certifying plumber, gasfitter and drainlayer, with the drainlaying registration exam passed in 2010
- Thirteen years of CCTV drain camera and pipe locating experience
- RIDGID mini see snake camera reaching up to 60 metres, with Tru Sense angle detection for diagnosing humps and slumps in underground pipe
- Drain inspections recorded with audio narration and supplied on a USB drive
- As built plans available once a drain has been traced
Location & Contact
Name: Sharp Plumbing Services
Address: 35 Moana Street, Whanganui 4500
Phone: 06 343 6297
Website: sharpplumbingservices.co.nz
3GROUNDED Company HQ Ltd
GROUNDED Company HQ is a family owned civil contracting business based at Fordell and run by Matt and Carol Loader, with 20 years in civil construction behind it. Certified drainlaying sits alongside earthworks, section levelling and concrete work, with trenching and pipe placement for stormwater and sewer systems handled in house. It suits anyone developing a section or subdivision who would rather have the drainage, the vehicle crossing and the ground preparation done by one team.
Services
- Certified drainlaying for stormwater and sewer systems
- Commercial and residential drainage
- Trenching and excavation for precise pipe placement
- Section levelling, grading and building site preparation
- Council approved vehicle crossings, driveways and retaining walls
Highlights
- Te Manu Atatū Māori Business Awards Supreme Award winner, 2025
- Trades and Construction Award at the same awards, 2025
- Whanganui District Council approved vehicle crossing installer
- Recognised by the Mayoral Taskforce for Jobs for commitment to training, 2025
- Rural work including placement and installation of tanks, water troughs and water lines
Location & Contact
Name: GROUNDED Company HQ Ltd
Address: Fordell, Whanganui
Phone: 027 556 2337
Website: groundedhq.co.nz
4Thompson Plumbing & Gas Ltd
Thompson Plumbing & Gas is a family run business operating from Putiki Drive and trading since April 2019, led by Jed Thompson, who is qualified in plumbing, gasfitting and drainlaying. Its drainlaying arm takes on new build drainage, rural drainage and wastewater systems as well as day to day blockages, and the team now numbers 14 after the business bought Graham Bull Plumbing in 2021 and Waverley Plumbing & Gas in 2023. It suits rural and lifestyle property owners who need septic or secondary treatment work alongside ordinary town drainage.
Services
- New build drainage
- Blocked drain solutions
- Rural drainage and commercial drainlaying
- Domestic and commercial wastewater systems, including septic tanks and secondary treatment systems
- Soak pits, stormwater drainage and backflow prevention
Highlights
- Certified plumbers, gasfitters and drainlayers
- Member of Master Plumbers
- Gold Award for New and Emerging Business and Bronze for Construction, Trades and Infrastructure at the Whanganui Regional Business Awards, 2024
- Approved installer for McDonald Concrete Group
Location & Contact
Name: Thompson Plumbing & Gas Ltd
Address: 83 Putiki Drive, Whanganui 4500
Phone: 06 345 0924
Website: thompsonplumbing.co.nz
5MB Plumbing
MB Plumbing works out of Bell Street in central Whanganui under director Mike Buchanan, with plumbers, gasfitters and drainlayers on the team. Its drainage work runs from designing and installing systems for new builds, including the consent applications and inspections, through to descaling and clearing lines that have stopped flowing. It suits homeowners who want the same firm for a drain emergency and the repair that follows it.
Services
- New build drainage design and installation
- Drain cleaning and unblocking
- Drain maintenance, inspection and descaling
- Emergency drain repairs
Highlights
- Handles drainage consent applications and inspections as part of a new build
- Emergency drain unblocking and repairs available around the clock
- Director Mike Buchanan has more than 40 years in the trade, supported by long serving staff including a plumber, gasfitter and drainlayer of 23 years with the business
Location & Contact
Name: MB Plumbing
Address: 62 Bell Street, Whanganui
Phone: 06 345 7111
Website: mbplumbing.co.nz
Drainage Contractors in Whanganui at a Glance
| Business | Highlight |
|---|---|
| Action Drainage & Construction | Twenty four hour emergency callout on the same Whanganui landline |
| Sharp Plumbing Services | Certifying plumber, gasfitter and drainlayer |
| GROUNDED Company HQ Ltd | Te Manu Atatū Māori Business Awards Supreme Award winner, 2025 |
| Thompson Plumbing & Gas Ltd | Certified plumbers, gasfitters and drainlayers |
| MB Plumbing | Handles drainage consent applications and inspections as part of a ne... |
How to Choose the Right Drainage Contractor in Whanganui
- Check that whoever does the drainlaying holds a current drainlaying licence, not only a plumbing ticket, because the two are separate registrations.
- Ask whether the firm owns its own excavator and drain camera. Subcontracting either one adds time and cost to a small job.
- For a drain that keeps blocking, look for a contractor who will locate and record the fault before quoting the repair, rather than clearing it and leaving.
- Match the firm to the work. A new subdivision, vehicle crossing or section level needs civil earthworks capability, while a blocked gully trap does not.
- Confirm who is handling the council consent application and the drainage inspections on new build work, so the paperwork does not stall the build.
Frequently Asked Questions About Whanganui Drainage Contractors
What does a drainage contractor actually do?
A drainage contractor installs, repairs and clears the pipes that carry wastewater and stormwater away from a property. That covers laying new sewer and stormwater lines on a build, connecting downpipes to soak pits or the kerb, repairing collapsed pipe, and clearing blockages caused by tree roots, grease or a slumped joint. On larger sites the same work extends to trenching, backfill and reinstatement.
How do I check a drainlayer is registered?
Drainlaying is licensed work in New Zealand. Anyone carrying out or certifying sanitary drainage has to hold a current licence, and you can search the public register held by the Plumbers, Gasfitters and Drainlayers Board by name or registration number. A plumbing licence on its own does not cover drainlaying, so it pays to check the specific trade.
Do I need council consent for new drainage work?
New sanitary drainage and connections to the public network generally need a building consent and an inspection before the trench is covered. Some smaller repairs are exempt. The Whanganui District Council sets the local requirements for connections, vehicle crossings and stormwater discharge, and several contractors will lodge the application on your behalf.
What does a CCTV drain inspection show?
A camera run through the line shows exactly where a pipe is broken, root bound, disjointed or sagging, and how deep the fault sits. Some cameras also read the angle of the pipe, which is how humps and slumps get diagnosed rather than guessed at. The recording doubles as evidence for a quote or an insurance claim, and a trace can be turned into an as built plan.
How much do drainage contractors in Whanganui charge?
Local firms do not generally publish fixed prices, because the variables are the depth of the drain, access for a machine and whether the surface has to be reinstated. Most quote after a site visit, and a straightforward unblock is charged very differently from a pipe replacement under a driveway. Ask whether the quote includes excavation, backfill and making good the surface.
Which parts of Whanganui do drainage contractors cover?
Whanganui is small enough that a drainage contractor will usually work the whole district rather than a single suburb, so being in Wanganui East, Putiki, Gonville or the central city makes little difference to a callout. Rural addresses are well served too, with operators based out at Fordell and coverage that often extends into the Rangitikei, Manawatū and South Taranaki.
Why does the same drain keep blocking?
A drain that blocks repeatedly almost always has a structural cause rather than a usage one. Tree roots finding a cracked joint, a section of pipe that has slumped and holds water, or an old earthenware line breaking down are the common culprits in older Whanganui housing. Clearing it treats the symptom, which is why a camera inspection before the second or third clear usually saves money.
Can a drainage contractor handle septic and rural systems?
Some can. Septic tanks, secondary treatment systems, effluent lines and farm drainage need different gear and different knowledge from town drainage, so it is worth asking directly whether a firm does rural work before booking. Several Whanganui drainlayers also install water tanks, troughs and rural water lines as part of the same visit.
How We Chose the Best Drainage Contractors in Whanganui
Every business in this guide was found by searching for drainage contractors in Whanganui, then checked against its own website. Names, addresses and phone numbers are taken from the business’s own site rather than a directory feed, so what you see here is what they publish themselves. We also check that each one is actually based in or genuinely serving Whanganui, rather than a national operator running a local landing page. A business with no website of its own is not listed, because there is no primary source to verify it against.