You probably haven’t heard the term “galvanic corrosion” unless you’ve dealt with serious pipe issues. But we have — a lot. And if your home in Sacramento has older plumbing, this hidden problem might already be working behind the walls.

At Golden Valley Plumbing, we’ve opened up walls that looked perfectly fine, only to find discolored, flaking, or outright crumbling connections inside. The cause? Two different types of metal reacting to each other — slowly eating the pipe from the inside out.

Let’s break it down, without the chemistry lecture.

What is galvanic corrosion?

When two dissimilar metals (like copper and steel) are connected with water flowing between them, they start a subtle chemical reaction. One metal gives up electrons faster — and that metal starts corroding. This doesn’t happen overnight. But over time, it creates leaks, weak spots, and in some cases, full pipe failure.

In Sacramento, we’ve seen this happen in:

• Older homes where galvanized steel was partially replaced with copper
• DIY repairs that mixed pipe types without proper fittings
• Water heaters connected with the wrong kind of union
• Outdoor plumbing where the weather accelerates the process

What does it look like?

This is what we find on the job:

• Greenish or white crust at pipe joints
• Flaky or bubbling pipe surfaces
• Discoloration where two metals meet
• Damp spots on drywall — even if the pipe looks “mostly okay” from the outside

Inside, the pipe walls often look jagged, eaten away, and full of mineral buildup. These leaks don’t gush — they drip just enough to quietly destroy what’s around them.

What can you do about it?

First, if your home is older and you’ve had small, unexplained leaks — get it checked. Galvanic corrosion is silent until it’s not.

Second, don’t mix and match pipe types without using dielectric unions — the special connectors that stop this reaction. We’ve replaced too many patch jobs that skipped this tiny, crucial detail.

And third, if you’re doing renovations or replacing fixtures, ask your plumber to take a look at what’s behind the wall. We’ve saved homeowners thousands by catching this early — and when needed, performing targeted repipe work to replace corroded lines before they failed completely.

Bottom line:
Galvanic corrosion sounds technical, but the damage is very real. If your home in Sacramento has mixed metal plumbing — or you’re not sure what’s behind your walls — call Golden Valley Plumbing. We know what to look for, and more importantly, how to stop it before it spreads.