Application field

Drinking Water ANALYSIS

ColiMinder™ is an instrument for real-time and online microbial analysis of drinking water
It is able to monitor microbiological quality of drinking water continuously.

Drinking Water Quality MONITORING

The quality of drinking water is essential as water is distributed throughout networks reaching thousands of people within a short period of time. Besides contamination resulting from external sources and being spread within a network, bacteria and microorganisms are able to grow within the system and act as an internal source of hazard.

The ColiMinder has proven its capability to ensure precise and reliable monitoring of microbiological contamination

• in drinking water treatment and production processes
• in drinking water distribution systems (networks and storage tanks)
• at raw water intakes for drinking water production

Performance and sensibility of the ColiMinder for drinking water analysis have been evaluated and proven to be the most sensitive available technology for monitoring of microbiological quality of drinking water.

Application example (picture on the left):

As part of a scientific study conducted by the University of Ghent, the ColiMinder monitors the microbial quality of drinking water supply in distribution systems in Belgium.

How does it work?

The ColiMinder measures the specific metabolic (enzymatic) activity of the target organisms present in the sample. The measured value provides information about the energy turnover of living organisms in the sample.

Living organisms need energy, which they gain through their metabolism, so the metabolic activity reflects the energetic turnover of the existing microorganisms. The measured activity directly indicates the microbiological quality of the water.


How do I use the ColiMinder?

ColiMinder can automatically monitor various process steps – critical control points – in drinking water treatment and production, providing a direct visualization of microbial dynamics of a processes.

The timeline displays any change in microbial contamination, providing precise and valuable information that was previously unavailable.

Since the results of the ColiMinder are available in near real time, microbiological water quality is now available as a parameter for process control. In addition, real-time alerts can be sent when defined bacterial contamination limits are exceeded.

The ColiMinder has proven its ability to measure the microbial quality of drinking water regardless of the type of microbes present. It reliably detects any type of contamination whether it is bacteria such as E. coli, coliforms, Pseudomonas, and other bacteria as well as algae, mold, yeast or biofilm.

Different add-on modules are available to ensure stable and reliable sampling and results.

How do I use the results?

The measured enzymatic activity of the sample provides a direct answer to the question: “how high is the microbiological contamination of the sample?”.

Depending on the reagent used, the measurement results are specific for the corresponding target organism.

The results not only provide direct quantitative information about the microbial contamination of the sample, but the shape and course of the measurement timeline  contain valuable information about the dynamics of the microbiological load and thus allow conclusions to be drawn about the causes of changes.


Sensitivity of the ColiMinder in drinking water measurement corresponds approximately to that of a determination of the heterotrophic plate count for 100ml sample.

A recent scientific study published in Water Research shows that the ColiMinder is the most sensitive instrument available on the market for measuring the microbial quality of water. Please see: Favere, J., Waegenaar, F., Boon, N., & De Gusseme, B. (2021). Online microbial monitoring of drinking water: How do different techniques respond to contaminations in practice? Water Research

Please see an overview here.


The reliability of the ColiMinder has been demonstrated in many installations where the devices have been providing reliable measurement results in continuous operation since 2015.


Thanks to the sophisticated system for fully automatic cleaning and calibration, the maintenance effort is limited to just refilling the consumables.


ColiMinder instruments calibrate themselves automatically at regular intervals, therefore no manual re-calibration is necessary.


The ColiMinder can measure any type of sample without

It has no problem with suspended solids or turbid samples. Even fluctuating background fluorescence has no effect on the measurement result.

Its robustness towards environmental influences, like temperature or humidity, is evident in installations like Stonecutter Island Sewage Treatment Plant in Hong Kong, where it has been monitoring effluent 24/7 since 2017 without any issues.

Its housing is IP65 protection class, measurement temperature range is 0°C to 40°C.

Can I do compliance testing with the ColiMinder?

The ColiMinder provides operational monitoring as recommended by the WHO, the EU Drinking Water Directive, and others.

Real-time measurement of microbiological quality enables rapid response and correction, so the ColiMinder helps you to meet specified limits at the lowest cost and with the highest level of safety.

A correlation between standard lab results and ColiMinder results can be established and used internally but the system is not intended to replace compliance testing.

Can ColiMinder results be expressed in CFU ?

In contrast to classical culture-based laboratory methods, which are based on the cultivation of bacteria, the enzymatic measurement method of the ColiMinder is based on the direct measurement of the metabolic activity of the target organisms. There is therefore no direct and generally valid conversion between the two methods.

In general, however, a correlation table can be created through comparative measurements, which can then be used for conversion.


Receive real-time warning

In case of contamination events

Monitor your process performance

In order to increase process efficiency, safety and sustainability

Learn more about your process

The result timelines (microbiological activity & turbidity) carry important
additional information about the dynamics of your system

Safeguard your water quality

during production as well as in storage facilities and distribution networks

Scan your distribution network quickly

in case of microbiological contamination events, to identify source of contamination

Avoid overdosing

Adjust disinfection intensity to actual contamination



Hover Text

Austrian municipal drinking water production from groundwater well: the ColiMinder monitoring raw water intake and after activated carbon filtration in alternating mode.


Hover Text

The Seoul Metropolitan Drinking Water Institute, Korea. The ColiMinder monitoring the performance of two different activated carbon filtration columns in alternating mode.


Hover Text

De Watergroep’s national drinking water network, Belgium: the ColiMinder is monitoring microbiological contamination level in semi final drinking water, detecting any deviation from baseline


Hover Text

The ColiMinder down under: in Unitywater’s drinking water network, it is safeguarding microbial quality of final drinking water, installed at remote BliBli reservoir.

Result timeline of a drinking water production

sample 1 (black) monitoring raw water intake and sample 2 (green) after activated carbon filtration

ColiMinder use cases

proven by customers!

The ColiMinder bacterial analyzer can be installed at any stage of a drinking water production process for real-time monitoring of microbiological contamination.

Raw water intakes

Filtration (Sand, AC, UF, NF, RO)

River bank filtration wells

Disinfection process

Groundwater wells

Storage tanks

Flocculation process

Distribution network

For more information:

Several White Papers on Drinking Water measurements can be found here in the download area to provide further information about drinking water measurements with the ColiMinder.


The ColiMinder™ had proven its reliability and stability in various applications world-wide


Austrian municipal drinking water production from groundwater well: the ColiMinder monitoring raw water intake and after activated carbon filtration in alternating mode.

Quick live introduction