When you invest in ocean buoys, one big question always comes up: how long will they last? The answer is not the same for everyone. Different buoys serve different jobs, face different conditions, and are built with different materials. At Sunhelmmarine, we often help shipowners, offshore operators, and fish farmers decide if their buoys are still safe to use or if it’s time to replace them. This article will walk you through the key points in plain language.
Why the lifespan of ocean buoys matters
If an ocean buoy fails, it can cause safety problems, data loss, or even accidents. For example:
- Shipowners and ports rely on navigation buoys for safe passage.
- Offshore wind and oil & gas companies use them for marking or monitoring.
- Fishing fleets and aquaculture farms depend on ocean buoys for mooring and daily operations.
A failed buoy can stop your work or damage your equipment. That’s why knowing when to repair or replace a buoy is important.
Types of ocean buoys and their average lifespan
- Drifting buoys – These are small units that float with the current and collect data. They don’t last long, usually between 1 month and 1.5 years. They are made for short missions.
- Data or observation buoys – These are larger, often anchored in one place. The buoy body can last close to 10 years if maintained, but the electronics, sensors, and batteries often need replacement every 2–3 years.
- Boias de navegação – Used for marking channels or hazards. With good maintenance, steel or polyethylene buoys can last around 10 years, and sometimes up to 20 years for modern plastic designs.
- Bóias de amarração – These take heavy loads from ships or fish cages. The buoy body itself may last many years, but the chains and shackles wear faster. Often, the mooring parts need replacement every few years depending on corrosion and wave action.





What affects the lifespan of a buoy?
Several factors decide how long a buoy really lasts:
- Environment – Strong waves, ice, or fast currents shorten life.
- Material – Steel is strong but rusts; plastic resists corrosion but can weaken under UV light.
- Marine growth – Barnacles and algae add weight and drag.
- Electronics – Batteries, solar panels, and sensors wear out faster than the buoy body.
- Accidents – Vessel collisions, fishing nets, or storms can damage ocean buoys quickly.
How to check if your buoy needs replacement
Look for these signs:
- Cracks, leaks, or visible rust on the body
- Chains, shackles, or anchor points worn or thinned by corrosion
- Sensors not sending stable data
- Batteries losing charge too quickly
- Buoy drifting from its position
If you see several of these issues, it might be cheaper and safer to replace the buoy rather than repair it again and again.
Maintenance tips to extend buoy life
- Inspect buoys regularly from the surface and underwater if possible.
- Clean off marine growth before it gets too heavy.
- Recoat or repaint steel buoys to protect against rust.
- Replace chains and shackles before they fail.
- Test electronics and change batteries on schedule.
Small, steady maintenance often adds years to a buoy’s service life and saves money in the long run.
When to repair, when to replace
- Repair when the buoy body is still strong, and only small parts or electronics need attention.
- Replace when the structure is damaged, maintenance costs are too high, or the buoy no longer meets safety or regulation standards.
Final thoughts from Sunhelmmarine
Every buoy has a different story, but the general rule is simple: the body lasts longer than the electronics and mooring gear. If you manage your maintenance well, a buoy can serve you reliably for many years. If you ignore problems, the lifespan will be cut short.
Em Sunhelmmarine, we provide inspections, maintenance support, and high-quality replacement buoys built for tough offshore conditions. If you are unsure about your current ocean buoys, we can help you decide whether to repair or replace them, so your operations stay safe and cost-efficient.
PERGUNTAS FREQUENTES
Q: My buoy is 8 years old but looks fine. Should I still replace it?
A: Not always. If inspections show the body and mooring are solid, you can continue using it, but check electronics and chains more often.
Q: The sensors keep failing. Do I need a new buoy?
A: Not necessarily. You may just need new electronics or batteries while keeping the same buoy body.
Q: How often should I replace mooring chains?
A: It depends on corrosion and wear, but many operators change them every 2–5 years.