Concrete Water Tank Liners — Fix a Leaking Tank for Good

Get a quote — call or send photos

Fill out the contact form and I'll get back to you soon!

Fastest: call Marcus and discuss your water tank — most liner quotes start with a phone call and a few photos of your tank.
No obligation, no call-out fee for a quote.

📞 0449 933 085

Prefer email? Please include the tank capacity (litres or dimensions - height x diameter) and town — you'll get a reply from concretewatertankrepairs@gmail.com.

Photos help a lot — text them to 0449 933 085 or email them to concretewatertankrepairs@gmail.com.
Best shots: the whole tank (helps me judge capacity), any visible damage, and the outlet so I can size the pipework.

Why concrete tanks leak — and why other solutions fail

Concrete water tanks crack — in the base, where the walls meet the base, and the walls themselves.

It's not a defect; it's the clay and soil underneath going through wet and dry cycles, working the tank a little with every season. The movement is minor, but concrete is inelastic — it can't flex with it, so it cracks.

Underground tanks hide even more. Because they're buried, a crack doesn't just leak out — water moves back and forth between the tank and the surrounding soil, so groundwater, roots and whatever's in the ground can work their way into the water you're drinking. Out of sight, but not out of mind.

Here's the key thing: structurally, your tank has likely got decades left in it. What it can no longer do is be both the structure and the waterproofing at the same time.

A liner separates those two jobs — A liner separates those two jobs — the concrete keeps doing the structural work, and the liner takes over the waterproofing.

That's also why a liner beats rendering or sealants: renders and coatings delaminate and crack again because they're bonded to a surface that keeps moving.

A liner isn't bonded — it allows for the movement.

Liners are food-safe and meets AS/NZS 4020 for the storage of drinking water, and it's no experiment: liners have been used in water storage tanks for over 40 years and are the industry standard for tank repair. That's why I can comfortably back mine with a 10-year warranty.

Cracked concrete water tank wall before liner installation

Cracked interior of an underground concrete water tank

How it works

From first phone call to a full tank — the whole process, no surprises.

Measure the tank

Marcus can callout & measure the tank, quote via email detailing your situation.

You can send measurements and photos yourself: estimated capacity, height x diameter, plus a few photos.

Free detailed quote, no obligation either way.

Manufacture Liner

Your liner is made to measure in Australia to the AS/NZS 4020 drinking water standard — allow 3–4 weeks.

CNC cut, triple checked, high frequency welded seams, best in class quality.

Once it's shipped, I'll call to arrange an installation date.

One-day install

Tank is vacuum cleaned, surfaces prepared, backing fabric installed for abrasion resistance, support post modifications, fit the liner, plumb it up — inlet, outlet, overflow — in a single day.

Ready for water that evening. We can help arrange a water carter.

Designed to last decades

Backed by a 10-year warranty on both the liner and the workmanship — with a working life of 20+ years, no problem.

Our installation method has a proven track record for over 12 years and counting.
Tank Fixed.

Liner vs crack repair vs new tank

The three ways to deal with a leaking concrete tank, honestly compared. We do all three — this is how we help you pick.

Option	The honest verdict	Longevity	Cost
Crack repair	We'd avoid it. Patching can fail after just a couple of wet/dry foundation cycles — regardless of workmanship — or it delaminates from the moving surface. Many products aren't food-safe either.	Most products fail within a couple of years	A little bit cheaper upfront — then paid for again
Tank liner	We use the highest-quality liners on the market — food-safe (AS/NZS 4020), moves with the tank, backing fabric protecting it from abrasion. Compatible with internal support posts. The same material the big brands use in new Colorbond tanks. Minimum hassle and a guaranteed fix.	10-year warranty, 20–30+ year life expected	A fraction of the cost of a new tank, only a 4 week lead time, a phone call and a couple of photos
New tank	Can be the right call for a smaller tanks or one that's severely damaged — but for most concrete tanks it's just the expensive, difficult option, especially as the tank you've already got can likely be repaired. Hidden costs, budget for site prep, redoing the plumbing and disposal of the old tank.	Decades	2–6× cost of a liner, with a 6–12 week lead time, maximum effort

Not sure which camp your tank is in? Send Marcus a few photos — you'll get a straight answer, even if that answer is "just patch it."

Designed to outlast the problem

10 yrwarranty — liner & workmanship

20–30+ yrexpected lifespan

1 dayinstallation
3-4 week lead time

22,500–100,000Lcommon tank sizes fitted

Every liner is Australian-made and certified to AS/NZS 4020 — the Australian standard for 'The Storage of Drinking Water'.

No taste, no chemicals, no worries — the same material the big brands use in their new Colorbond tanks.

And they last: we've been called out to replace liners that were installed in the 1970s that are only now reaching the end of their run. Liners work in concrete and metal tanks — above ground or below - compatible with tank that have internal support posts — roof remains on during installation.

Our installation method has a track record of 12 years and counting. We trust it.

Liners complete, in various locations

Concrete tank fitted with a new liner, refilling with water — New roof on the way. 100,000L tank being refilled for stock straight after the install.
Narrandera, NSW.

Completed tank liner with walls and floor fully lined under the original roof — 90,000L Tank complete, ready for water, original roof retained.
Tangambalanga, VIC.

Finished tank liner with sealed outlet penetrations — 45,000L Concrete tank with concrete roof, support post maintained.
Mansfield, VIC.

New liner fitted to a large open concrete tank — 80,000L liner complete. About to be refilled with bore water.
Corowa, NSW.

Tank liner installed in a roofed concrete tank — Concrete roof tank, liner complete. 45,000L support post maintained.
Shepparton, VIC.

Tank liner installed in an underground concrete tank — Oval shaped 42,000L tank. Custom liner shape. Complete and ready for rain.
Markwood, VIC.

What a finished job looks like: the liner runs wall-to-wall and floor-to-ceiling in one continuous membrane, every pipe penetration sealed, roof support posts accommodated, and each liner carries its factory job number — custom-made for that tank and no other. Whether it's an open farm tank, a roofed tank, or one tucked under the house, the result is the same: a tank that holds every drop again.

Tank liner questions

How much does a water tank liner cost?

Every tank is quoted individually — size, condition, outlet size and access all matter. Call and let us know your location, tank capacity and a couple of photos, or we can come to you, and Marcus will discuss the job with you and give you a obligation free quote and an honest price. Most rural tanks we line are between 22,500L and 100,000L, either concrete roof or metal roof is no issue.

How long does a tank liner last?

The 10-year warranty covers both the liner and our workmanship, and the working life is 20+ years — likely 30 or more without damage. We regularly replace liners from the 1970s and '80s that are only now wearing out.

Is the liner safe for drinking water?

Yes — Australian-made and certified to AS/NZS 4020, the standard for products in contact with drinking water. It imparts no taste or chemicals.

How long until my tank is back in service?

The liner is custom-made for your tank, which takes 3–4 weeks. Installation itself is done in a single day, and you can refill immediately — we can organise a water carter if you don't want to wait for rain or haven't got access to bore water etc.

My tank is badly cracked — is it too far gone for a liner?

Usually not. As long as the tank is structurally standing, a liner doesn't care how cracked the concrete is — that's the whole point. If a tank genuinely is beyond lining, Marcus will tell you straight and talk through replacement options. We do not want to warranty a tank that is beyond repair, but it's very rare that a tank can't be fixed due to the reinforcement in the concrete.

Do liners work in metal and corrugated tanks?

Yes — liners suit concrete, metal and corrugated tanks, above ground or underground, with or without internal support posts, we can manage it.

Does my tank roof have to come off?

No. Most liners go into tanks with the roof left in place — the liner goes in through the existing access hatch. No crane, no removing the roof, no rebuilding it afterwards. It's the most common assumption people get wrong about liners, and it puts them off calling.

Can a liner be installed in an underground tank?

Yes. Underground and partially buried tanks are lined regularly. Access is the main variable — I'll want to know the hatch size and how the tank sits in the ground before quoting.

What happens to my existing outlets and fittings?

They're sealed through the liner with proper flanged fittings, so your existing pipework keeps working. Outlet size and position are things I check when quoting, because they affect the liner spec.

Will I lose much capacity?

Negligible. The liner sits against the wall and floor — you're losing the thickness of the material, not any usable volume.

What if my tank is still holding water?

It needs to be empty and clean for the liner to go in. If there's sludge on the floor I'll vacuum it out first — that's usually done as part of the same job rather than a separate visit.

The end of your tank problems.

Get a quote — call or send photos

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