Borehole pumps

HOW TO AVOID CORROSION IN COPPER PIPE

One of the most significant milestones in our lives is when we are finally able to purchase a property!  It’s something most people dream of and work diligently towards achieving. It takes hard work and effort to achieve this so naturally, you want to make sure you do everything in your power to take care of it.  If your property has copper piping and you’re using borehole or well-point water then it’s imperative to ensure that you avoid corrosion in your copper pipe.  This is due to the cost of plumbing repairs, expenses that can arise from repairing water-damaged materials, and even mold issues.  It’s simply not something that can or should be ignored!

Copper has typically been a favored choice for piping water to numerous households.  The reason for this is obvious when you consider the fact that it has strong corrosion resistance and can last for many years.  It seems to be an easy, clear-cut choice, doesn’t it? 

While copper piping is generally a safe choice when it comes to council water it’s another story entirely when it comes to water sourced from well-points and boreholes.  Corrosion of copper piping is typically associated with water that is used from a borehole or well-point.

“Research into the mechanism of pitting corrosion has been undertaken by the copper industry in many countries of the world.  Pitting occurs typically in cold, aerated, hard, organically pure waters from deep wells or boreholes and not in surface waters as generally used”.

When you decide to drill a well-point or borehole and use that water inside your home by means of copper piping you need to test it first and treat it if necessary to ensure you don’t end up with copper corrosion issues.

Let’s take a closer look now at what copper pipe corrosion is.

WHAT IS COPPER PIPE CORROSION?

According to Wikipedia, corrosion is defined as “the gradual destruction of materials (usually a metal) by chemical and/or electrochemical reaction with their environment”. As a result, when copper pipes are used to convey water, they can become susceptible to erosion.  While copper is corrosion resistant it is not corrosion-proof.  What this means is that when it is exposed to specific chemicals found in water, in particular, those found in borehole or well point water, then corrosion can occur over time.

WHAT ARE SOME OF THE MAIN CAUSES OF COPPER PIPE CORROSION?

1. pH levels of the water
2. High levels of dissolved oxygen
3. High levels of salts dissolved in the water
4. High velocity of the water

Let’s take a closer look now at each of these causes:

1. PH LEVELS OF THE WATER

To understand this let’s first look at what pH actually means.  pH is a way to measure the electrically charged particles in a substance.  It shows whether the water is acidic, neutral, or alkaline based on a reading from a pH scale that ranges from 0 – 14.  A reading between 0 – 6 indicates that it’s acidic with the most acidic substances showing a pH of 0.  A reading between 8 – 14 indicates alkalinity.  A pH reading of 7 indicates pure water because 7 is neutral.  It’s neither acidic nor alkaline.

In light of this, we can see that a high acidic pH level in the water will increase corrosion by providing hydrogen ions to the corrosion process.  

As a result, it’s important to note that water with a pH between 7.0 and 8.2 is usually not corrosive.  By contrast, water that shows a pH of 6.5 and below will be corrosive.

2. HIGH LEVELS OF DISSOLVED OXYGEN

Dissolved oxygen is the amount of oxygen found in water.  Numerous metals are coated with a protective hydrogen film but this can be destroyed by dissolved oxygen.  As a result, oxygen comes into contact with the copper and oxides it which causes the pipes to rust.

3. HIGH LEVELS OF SALTS DISSOLVED IN THE WATER

When it comes to corrosion from high levels of salt, copper is the metal that is most susceptible to it.  High salt levels in the water contribute to corrosion because it’s an electrolyte.  As a result, it conducts ions which accelerates the rusting process.

4. HIGH VELOCITY OF THE WATER

This can cause corrosion as the abrasive particles in the water scour against and erode the protective film which is usually found on the inside surface of the pipes.  This can lead to pinholes forming in the pipes and ultimately to corrosion.

WHAT TYPE OF CORROSION CAN OCCUR?

The main type of erosion that occurs in copper pipes is pitting corrosion.  Here’s how it works.  When the copper pipe comes into contact with chemicals like chloride, hypochlorite, or bromide ions that are found in the water it causes a reaction on the copper.  It starts as little patches that have the appearance of a greenish spot.  These weaken the copper over time which causes pinhole leaks.  These can be difficult to locate and can lead to much damage and water wastage.  

Now that we understand copper pipe corrosion and have looked at what causes it, let’s explore the various options available to you to deal with it.

The first step is to draw a water sample and have it tested at a laboratory.  They will give you a full report on the quality of your water. Your water systems specialist will treat your water according to these results.

PLEASE CLICK HERE TO GET A WATER SAMPLE DONE TODAY

 The important thing to note is that they will indicate the correct amount for each substance.  It will also let you know if your water is on par and can be used for drinking water.  It’s very important to take note of the Langelier index which tells you how corrosive the water is.

4 WAYS TO DEAL WITH COPPER PIPE CORROSION

1. PH LEVELS

If the laboratory tests show that the pH levels of your water are too acidic then a corrosion-resistant chemical feed pump will be installed that will release sodium hydroxide solution into the water.  This will raise the pH level of your water making it alkaline.  Ideally, you are looking to have the pH level around 7 for your water.

Alternatively, a pressure vessel filled with calcite can also be used to raise the pH level of your water.

2. HIGH LEVELS OF DISSOLVED OXYGEN

Reducing dissolved oxygen levels can be challenging.  However, a flexible membrane or floating disc can be added to the pressure tank.  This will help reduce the water’s contact with air.

3. HIGH LEVELS OF SALTS DISSOLVED IN THE WATER

If your water testing results reveal that your salt levels are too high then a reverse osmosis system will need to be installed.

Reverse osmosis refers to the way in which water is processed and treated so that salts are removed from the water.  This is achieved by using pressure that forces the water molecules through a semipermeable membrane.  As a result, the salt gets trapped in the semipermeable membrane where it is filtered and flushed out.  All that’s left now is clean drinking water.

4. HIGH VELOCITY OF THE WATER

If you need to reduce the flow rate (velocity) of your water then consider using larger diameter pipes which can slow the flow rate of the water down.

The velocity for a pipe with cold water should be around 2.4 meters per second.  

Copper pipe corrosion can be a factor for people using underground borehole and well-point water.  However, it’s something that can be addressed and dealt with through the above-mentioned methods.  

In these uncertain times in which we live having your own source of water is essential.  Equally essential is ensuring your underground water is clean, drinkable, and not running through corroded copper pipes.  It takes a willingness to be proactive and the decision to invest some money into it but it’s the best investment you’ll ever make! Never forget, water is life!