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What is Dye Testing?

13th October 2021

What is Dye Testing?

Drainage systems can be complicated and working out all the connections and water flow from above ground can be especially challenging to decipher.

Our expert team of engineers are trained in all things drains and are here to help if you need to identify where a problem lies. To do this we often use dye testing techniques to identify the water flow around a property. You can read more about the drain dye testing process and its uses below.

What is Drain Dye Testing?

Drain dye, or specifically tracing dye, is used for detecting the flow of water throughout drains or pipes connected to a property. It is used as a technique when identifying individual drain flows into a common drain system, as well as tracing missed connections of foul water into rivers and streams.

When is Drain Dye Testing Used?

We often use dye testing where there is a problem in the drainage system, and we are not sure where a series of drains connect to. Dye testing is a useful aid to ensure environmental conformity to make sure that all the foul water and surface water connects into the correct drainage systems.

What Does Dye Tracing Involve?

Drain dye testing can be used within any property that is connected to the sewage system to inspect water flows in the pipework.

Dye testing is a simple process that involves adding environmentally friendly and biodegradable coloured dye to water flows around the home, such as sinks, toilets and outside drains to track the flow of water to the sewer. This water can then be inspected along the drainage route or at manholes and inspection ports to observe the dyed water flow through the drainage system. The water dye disperses naturally in a short period of time, leaving no residue.

Dye testing helps to locate cross-connections in existing pipework, as well as problems with leaking and the infiltration of rainwater from outside.

Dye testing can be carried out in combination with drain mapping to locate property pipes and water flows, helping to identify issues and keep your drains in working condition.

What is Drain Dye?

Concentrated drain dyes come in a variety of colours to differentiate different water flows around the home or property.

Fluorescent dyes are also available and can be seen using ultra-violet light, so they can even be traced at night.

Once mixed with cold water, non-toxic tracing dye can be poured directly into drains, toilet bowls, or sinks. It's an excellent way of tracing and locating underground drains as it follows the flow of pipes. By diluting powdered drain dyes into water, the coloured or fluorescent dye will leave a coloured trace on any liquid it comes into contact with.

The Step-by-Step Dye Testing Process

Our experts follow a simple process to ensure that the drain dye is used effectively and efficiently to help map your drains.

  1. Mix concreted dye into cold water, using a bucket for easy pouring.
  2. Add the dyed water directly into the water flow via a drain, toilet, sink etc.
  3. Get ready to inspect the water flow at an outside manhole inspection point
  4. Identify which pipes are used from particular water flow start points
  5. Note any leaks in the drainage system causing the dye to disperse into surrounding areas of the property
  6. Map the entire water flow drain system noting any slow flows or problem leaks
  7. Repeat the process once the fixes to pipework have been installed in problem areas.

Give the Drain Experts a Call

Dye testing is just one of the techniques Metro Rod use to solve problems in your pipework and drainage system.

We are able to combine it with our expert techniques to access any problem you may be having with your drains, to be sure the right solution is applied for a safe and effective result. This is a simple, quick, cost-effective and environmentally friendly technique for identifying the outfall of many drainage services.

If your home or business needs a professional and reliable drainage service, give us a call today on 0800 66 88 00. Our nationwide network of over 450 engineers are available around the clock, 365 days of the year for all of your drainage needs.

Talk to you local metrorod specialist

Talk to your local Metro Rod specialist

We are always happy to arrange a free site assessment and no obligation quotations for any work you might need. Alternatively, you can call our emergency hotline number on 0800 66 88 00

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