Finding the best water tank installation in Invercargill starts with matching the tank to the job, whether that is a rainwater tank for a lifestyle block, a buried concrete tank under a new build, or a large storage reservoir for a farm or factory. The businesses below supply and install concrete, plastic and steel water tanks for rainwater harvesting, backup supply, firefighting and irrigation across Invercargill and Southland. For concrete tanks made locally, Harvey Tanks in Winton is a long-established name, while Rohan Mahon Plumbing & Drainlaying handles water tank installation in Invercargill alongside drainage and plumbing on the same site.
1Harvey Tanks
Harvey Tanks is a family-owned concrete tank manufacturer founded by Cecil Harvey in 1950 and now run by the third generation of the Harvey family from its factory at Winton, about 30 minutes north of Invercargill. It makes concrete water tanks from 5,000 to 22,500 litres in standard and underground designs, delivers them by its own Hiab truck, and assists local contractors with installation. It suits rural, residential, commercial and industrial properties across Southland and South and Central Otago.
Services
- Standard concrete water tanks (10,000L, 15,000L and 22,500L)
- Underground concrete water tanks (5,000L to 22,500L)
- Hiab truck delivery and placement on site
- Installation assistance with your local contractor
- Concrete septic tanks and dairy effluent tanks
Highlights
- Family business established in 1950, now in its third generation
- Tanks built by the gunite (shotcrete) method as solid concrete rather than hand-plastered layers
- Underground tanks can be fully buried with a reinforced roof
- Owner Rhys Harvey has more than 30 years in the concrete tank industry
Location & Contact
Name: Harvey Tanks Ltd
Address: 149 Gap Road West, Winton 9781
Phone: 03 236 8731
Website: harveytanks.co.nz
2Rohan Mahon Plumbing & Drainlaying
Rohan Mahon Plumbing & Drainlaying is a small Invercargill-based team led by Rohan Mahon, a certified craftsman plumber and certified drainlayer who started the business in 2014. Water tanks sit within its drainlaying work: the team supplies and installs above-ground and below-ground concrete and plastic tanks and can connect them to pumps, diverters and stormwater on the same job. It suits homeowners and builders from Invercargill and Bluff through to Riverton, Winton, Gore and Te Anau.
Services
- Above-ground and below-ground concrete and plastic water tanks
- Tanks for rainwater harvesting, firefighting, irrigation and backup supply
- Retention and detention tanks
- First flush diverters, pump stations and sump pumps
- Septic and onsite wastewater system installation
Highlights
- Owner holds Certified Craftsman Plumber and Certified Drainlayer registration
- Southland agent for Oasis Clearwater wastewater systems
- Established in 2014 after Rohan trained in his family’s plumbing business from 2005
Location & Contact
Name: Rohan Mahon Plumbing & Drainlaying
Address: Invercargill
Phone: 027 535 0440
Website: rmplumbing.co.nz
3Inside Systems Limited
Inside Systems Limited (ISL) is a plumbing, drainage and heating company on Eye Street in Appleby, Invercargill, serving homes and businesses across Southland and Central Otago. Among its plumbing services it supplies and installs both concrete and plastic water tanks for residential and commercial use, along with the pumps that move water from the tank to the house. It suits property owners who want tank, pump and plumbing work handled by one team.
Services
- Concrete and plastic water tank supply and installation
- Water transfer, greywater and sewerage pump installation
- Spouting and guttering installation and repairs
- Hot water cylinders and hot water heat pumps
Highlights
- More than 30 years of plumbing experience
- Member of Master Plumbers & Gasfitters and IRHAC
- SiteWise Gold health and safety accreditation
- Pump brands include Onga, Grundfos and Wilo
- Free quotes
Location & Contact
Name: Inside Systems Limited
Address: 121 Eye Street, Appleby, Invercargill 9812
Phone: 03 218 8919
Website: insidesystems.co.nz
4Reliant Solutions
Reliant Solutions is an Invercargill-headquartered design and build contractor for large bolted steel storage tanks, working throughout New Zealand and Australia as the Australasian distributor and installer of Permastore glass-fused-to-steel tanks. Its potable water tanks and reservoirs are built for councils, dairy factories, farms and industrial sites rather than individual homes. It suits projects that need water storage well beyond the size of a standard rainwater tank.
Services
- Potable water storage tanks and reservoirs
- Firewater storage tanks
- Water standpipes and elevated distribution tanks
- Wastewater and agricultural effluent storage tanks
- Tank refurbishment and ROV underwater tank inspection
Highlights
- Australasian distributor and installer of Permastore glass-fused-to-steel tanks
- Glass-fused-to-steel tank system carries NSF/ANSI 61 certification for drinking water
- Manages feasibility, design, project management and tank erection in house
- Installed a bolted tank of 12,600,000 litres capacity, 47.8 metres in diameter
Location & Contact
Name: Reliant Solutions
Address: 32 Benmore Street, Prestonville, Invercargill 9810
Phone: 03 215 9125
Website: reliant-solutions.co.nz
Water Tank Installation in Invercargill at a Glance
| Business | Highlight |
|---|---|
| Harvey Tanks | Family business established in 1950, now in its third generation |
| Rohan Mahon Plumbing & Drainlaying | Owner holds Certified Craftsman Plumber and Certified Drainlayer regi... |
| Inside Systems Limited | More than 30 years of plumbing experience |
| Reliant Solutions | Australasian distributor and installer of Permastore glass-fused-to-s... |
How to Choose the Right Water Tank Installation in Invercargill
- Tank material: concrete keeps water cool and dark and suits burying, plastic is lighter and quicker to place, and bolted steel suits very large volumes.
- Above or below ground: an underground tank saves space and hides the tank but needs excavation, a reinforced lid and good site access for the delivery truck.
- Plumbing connections: ask who will fit the pump, first flush diverter and pipework, and whether that person is a registered plumber or drainlayer.
- Site access and preparation: check the truck and crane access and how the base must be prepared before delivery day.
- Purpose and size: household drinking water, firefighting reserve, stock water and stormwater detention each call for different tank sizes and fittings.
Frequently Asked Questions About Invercargill Water Tank Installation
Should I choose a concrete or plastic water tank in Invercargill?
Concrete tanks are heavy, stay put when empty, keep water cool and can be partly or fully buried. Plastic tanks cost less to transport and are easier to place on tight sites. Many installers in Southland handle both, so it is worth asking for a quote on each.
Can a water tank be installed underground?
Yes. Underground concrete tanks are made with thicker walls and reinforced lids for burying, and some plastic tanks are rated for below-ground use. An underground install needs excavation and drainage work, so a drainlayer or plumber usually handles the connections.
Do I need a building consent for a water tank?
Some tank installations are exempt from building consent and others are not, depending on size, height and where the tank sits. Check the exemption guidance on building.govt.nz and confirm with Invercargill City Council before work starts.
How do I check that my water tank installer is registered?
Connecting a tank to household plumbing or drains is sanitary plumbing or drainlaying work, which must be done or supervised by an authorised person. You can search the public register on the Plumbers, Gasfitters and Drainlayers Board website.
What size water tank do I need?
It depends on your roof area, household water use and whether the tank is your only supply or a backup. Common residential sizes range from about 5,000 to 25,000 litres, and a farm or firefighting reserve may need far more. An installer can size the tank from your roof catchment and usage.
What is a first flush diverter?
A first flush diverter sends the first rain off the roof away from the tank, carrying dust, leaves and bird droppings with it. It is a simple fitting that helps keep stored rainwater cleaner and is usually added when the downpipes are connected.
Which parts of Invercargill and Southland do these water tank installers cover?
Water tank installers in Invercargill generally work right across the city, from Appleby to Prestonville, and many also travel out to Bluff, Riverton, Winton and Gore. Concrete tank manufacturers in rural Southland deliver by truck throughout the region, so farms and lifestyle blocks outside the city are well served too.
How long does a water tank installation take?
Placing an above-ground tank on a prepared base can take a few hours once it arrives. A buried tank or one that needs new pumps and pipework takes longer because of excavation and connections, so ask your installer for a timeline when you get a quote.
How We Chose the Best Water Tank Installation in Invercargill
Every business in this guide was found by searching for water tank installation in Invercargill, then checked against what the business publishes itself: its own website, or where it has none, its official social or booking page. Names, addresses and phone numbers come from those pages rather than a directory feed, so what you see here is what the business says about itself. We also check that each one is still trading and is actually based in or genuinely serving Invercargill, rather than a national operator running a local landing page. A business we can’t confirm from its own pages is not listed.