Electrolysis May Be Damaging Your Copper Pipes

If your plumbing system includes copper piping and you’ve noticed unexpected leaks or signs of pitting, electrolysis may be the reason.

This May Also Interest You: How to Use a Drain Snake and Unclog Your Toilet

Damage from electrolysis to copper pipes is a less obvious but very real problem that can lead to expensive repairs. Left unchecked, this process can slowly erode your pipes, even if your water quality appears fine and your system seems modern and well-maintained.

What Is Electrolysis, and Why Does It Affect My Copper Pipes?

Electrolysis in plumbing refers to an electrochemical reaction that happens when stray electric currents pass through your water line or when dissimilar metals are connected within the same system. These currents can cause copper to dissolve over time, creating small holes or “pits” in the pipe wall.

This process is a major contributor to copper pipe pitting, which often goes undetected until a pipe begins to leak. Unlike corrosion caused by water chemistry alone, electrolysis damage can accelerate when your electrical system isn't properly grounded or when your plumbing system includes a mix of materials.

How Does This Happen?

Electrolysis can occur when electric wiring or household appliances introduce stray current into your plumbing system. It often starts where copper pipes are in contact with steel supports or valves made from different metals. The problem is widespread in homes that combine copper with galvanized steel or brass fittings. This combination creates a small electrical current between the dissimilar metals, which results in metal loss from the copper pipe.

Another source of damage is improper grounding. If your electrical system uses copper pipes as a grounding path — a common practice once— any flaw in that grounding system may allow electricity to flow through the water pipe. This causes electrochemical pipe damage over time, especially in areas where metal plumbing comes into contact with the soil or concrete foundations.

Stray current corrosion on pipes is also a growing concern in older homes or areas where power lines aren't well insulated. Even something as simple as a nearby lightning strike can introduce stray voltage into the ground, which then travels through your copper pipes if they're part of the grounding network.

Warning Signs of Corrosion

The signs of electrolysis in copper pipes may not be dramatic at first, but they're serious indicators:

• Pinhole leaks in otherwise solid copper pipes

• Unexplained wet spots on walls or ceilings

• Green or bluish corrosion at joints or fittings

• Discoloration or a metallic taste in tap water

• Frequent plumbing failures in localized areas

If you’ve ruled out basic water pipe corrosion causes, electrolysis may be the hidden culprit behind these problems. It’s more common in mixed-material plumbing systems or homes with outdated electrical grounding.

More Related Articles:

• Snake’s in a Drain! How to Unclog Your Sink With a Drain Snake

• Checked Your Storm Drains Lately? Here’s a List of Maintenance Tasks

• Prevent Frozen-Pipe Problems by Knowing These Things Down Cold

• Pipe Burst? Here’s What to Do Next

• Au Revoir, Standing Water! How to Install a French Drain in 8 Steps

How Can I Prevent Electrolysis From Damaging My Copper Pipes?

The most effective strategy for pipe electrolysis prevention is to eliminate sources of stray electrical current. Here are a few practical steps you can take:

• Install dielectric unions. These are fittings that separate dissimilar metals using a nonconductive material. They're commonly used where copper connects to steel, helping prevent electrochemical reactions.

• Upgrade your grounding. Make sure your electrical system is properly grounded and doesn't rely on copper pipes to carry current. Licensed electricians can reroute grounding to avoid water lines altogether.

• Use plastic piping as a buffer. Replacing a short section of your water line with plastic piping can help interrupt the path of stray electric currents. This is particularly useful where plumbing enters the house or near appliances that may produce electrical interference.

• Regular inspections. A plumber can check for telltale signs of electrolysis and test your system for stray voltage. Addressing the problem early can save you from more costly pipe replacements later.

• Monitor for pitting or corrosion. If you’ve had previous leaks or repairs, ask your plumber to check the condition of surrounding copper pipes. Early-stage copper pipe pitting is often a sign that electrolysis is occurring, even if no leaks are visible yet.

Preventing Leaks Is Important

Water pipe electrolysis damage can quietly degrade your home’s infrastructure. Even a small pinhole leak can lead to mold growth, increased water bills or structural damage if it occurs behind a wall. By understanding how electrolysis can occur and knowing the common triggers — such as when two dissimilar metals are joined or when there’s a faulty ground — you can take practical steps to protect your copper pipes.