For many households and farms across Northern NSW and South QLD, rainwater tanks are a lifeline. But after Cyclone Alfred’s intense winds and heavy rainfall, it’s crucial to check for leaks and water loss. Even small leaks can waste thousands of litres of water, drive up costs, and leave you without a reliable water supply when you need it most.
Whether you’ve just been through extreme weather or simply want to ensure your water tank is in top shape, this guide will help you detect a leaking water tank, troubleshoot common issues, and fix them fast.
How to Tell If Your Water Tank is Leaking
Some water tank leaks are obvious, while others can be slow and difficult to detect. Here’s how to check:
Visual Signs of a Leak
✔️ Wet patches around the base of the tank – Even if it hasn’t rained, standing water or damp soil could indicate a slow leak.
✔️ Water trickling from seams, fittings, or cracks – Look closely, especially near pipe connections and valves.
✔️ Discolouration or algae growth – Damp areas on the tank’s exterior can encourage algae and mould growth.
✔️ Rust or corrosion (for steel tanks) – This could weaken structural integrity and lead to leaks.
Water Level Drop Test
1️⃣ Mark the water level inside your tank.
2️⃣ Turn off pumps and any water usage for at least 24 hours.
3️⃣ Check if the water level has dropped – If it has and there’s no external use, you likely have a leak.
Listen for Leaks
If your tank is quiet, listen carefully for hissing, dripping, or trickling sounds that could indicate water escaping from a crack or faulty fitting.
Common Causes of Water Tank Leaks
Understanding why your water tank is leaking can help you fix it quickly and prevent future damage.
Post-Storm Damage (Cyclone Alfred & Other Extreme Weather)
- Flying debris or strong winds may have cracked or dented your tank.
- Heavy rainfall and flooding could have shifted the base, causing stress on the tank walls.
- Overflow pipe blockages can create pressure buildup, leading to leaks.
Structural Issues
- Small cracks in poly tanks – Can form over time or after extreme heat/cold fluctuations.
- Seam leaks in steel tanks – Caused by rust or poor welding over time.
- Loose fittings and pipe connections – Movement from storms or general wear and tear can create leaks at joints.
Contamination & Biological Growth
- Tree roots seeking water can infiltrate underground or partially buried tanks.
- Algae buildup inside tanks can corrode materials, leading to leaks.
- Sediment buildup at the base can put stress on the tank’s structure.
How to Fix a Leaking Water Tank Fast
Once you’ve identified a leak, the next step is fixing it as quickly as possible to prevent further water loss. The repair method depends on the type of tank and the severity of the leak.
Fixing Small Cracks in Poly Water Tanks
✅ Poly Welding (Permanent Fix) – If the crack is small to medium-sized, a poly welding kit can heat and fuse the material back together.
✅ Plastic Tank Sealant – Food-safe, waterproof epoxy can be applied over small cracks or pinholes.
✅ Waterproof Tape or Patch Kits (Temporary Fix) – Great for emergency repairs until a permanent solution is applied.
Fixing Leaks in Steel Water Tanks
✅ Seal with a Waterproof Tank Liner – If corrosion has led to multiple leaks, a liner can restore full water-tightness.
✅ Epoxy or Silicone Sealants – Apply food-grade sealants over small cracks and seams.
✅ Replace Rusted Panels or Rivets – For larger damage, replacement parts may be required.
Repairing Leaking Pipes & Fittings
✅ Tighten Loose Connections – Check all outlets, overflow pipes, and inlets for loose seals.
✅ Replace Worn-Out Washers & Gaskets – Rubber seals can degrade over time, causing slow leaks.
✅ Use Plumber’s Tape on Threaded Joints – Helps prevent small leaks in pipe fittings.
Important: If you’re dealing with major cracks, structural failure, or ongoing leaks, it may be safer and more cost-effective to replace the tank rather than continuously repair it.
When to Consider Replacing Your Water Tank
If your tank has multiple leaks, severe cracks, or persistent issues, it may be time to invest in a new, high-quality tank built to withstand Australia’s extreme conditions.
If your poly tank has large cracks or structural warping, repairs may only be temporary.
If your steel tank has extensive rust or failing seams, a replacement is often the safest long-term solution.
If your tank base has shifted due to flooding, it may lead to ongoing damage even after repairs.
Ready to replace? Our team at The Water Tank Factory can help you find a long-lasting, tough, high-quality water tank suited to your needs. Call 1300 826 532 , our friendly, expert team are on standby to help.
How to Prevent Water Tank Leaks in the Future
A few simple maintenance habits can help extend the lifespan of your tank and prevent costly water loss:
✔️ Inspect Your Tank Monthly – Look for small cracks, leaks, or loose fittings before they become big problems.
✔️ Keep Gutters & Pipes Clean – Prevent overflow and pressure build-up by maintaining clear pathways.
✔️ Secure Your Tank in Storm Season – Ensure your tank is anchored and fittings are reinforced.
✔️ Flush Your Tank Yearly – Remove sediment that could put stress on the base and walls.
✔️ Invest in a Quality Tank – A well-built tank, like those from The Water Tank Factory, can last for decades with proper care.
Final Thoughts: Act Fast to Stop Water Loss
A leaking water tank doesn’t just waste water—it can lead to contamination, structural damage, and costly repairs. By detecting leaks early, taking quick action, and maintaining your tank properly, you can protect your water supply for years to come.
If you’re unsure whether your tank needs repairs or replacement, we’re here to help. Visit The Water Tank Factory for expert advice on high-quality, storm-resistant tanks built for Australian conditions.