UNIC study finds no proof Cyprus water pipes corroded by microorganisms  

A preliminary study conducted by the University of Nicosia’s Environmental Health Research Centre found no evidence of microbiologically-influenced corrosion (MIC) in Cyprus’ drinking water pipes, despite detecting microbial presence in all samples examined.

The research, part of the CyMIC project funded by the Research and Innovation Foundation of Cyprus, examined whether microorganisms were causing or accelerating corrosion in the country’s water distribution systems. Contrary to initial concerns, researchers could not confirm the potential involvement of microbiologically-influenced corrosion in the drinking water pipes evaluated.

Key research findings

The study’s results suggest that biofilm present in the pipes could actually be involved in maintaining biostable and high-quality drinking water, rather than causing corrosion. While microbial presence was detected in all samples examined, with consistently higher levels in metal connectors compared to plastic pipes, this microbial activity does not appear to be contributing to pipe deterioration.

However, researchers emphasise that more extensive research is required, particularly considering the challenges facing Cyprus’s water network infrastructure.

Project background

The CyMIC (MIC involvement in damaged water pipes) project (CONCEPT/0823/0479), funded by the Research and Innovation Foundation of Cyprus under the Proof of Concept for Technology/Knowhow Applications RESTART 2016-2020 Programme, evaluated microbial presence in metal and plastic pipes and drinking water samples obtained from scheduled works for replacing leaking pipes.

The research team comprises Professor Edna N. Yamasaki, Elena Patrikiou and Kyriakos E. Georgiou from the University of Nicosia’s Environmental Health Research Centre, working in collaboration with Dr Torben L. Skovhus from the Research Centre for Built Environment, Climate and Water Technology, VIA University College, Horsens, Denmark.

Cyprus water context

Cyprus ranks among the five most water-stressed countries globally. The combination of extreme summer heat, droughts and significant water losses from the distribution system critically affects drinking water availability. Distribution losses, categorised as non-revenue water, represent a major challenge within drinking water networks. Local district government departments have established systems to detect leaks and implement programmed replacements of obsolete water supply networks.

Cyprus’ drinking water originates from dams collecting rainwater, boreholes and desalinated water. The treatment process involves pre-chlorination, aeration, flocculation, sedimentation, filtering, lime dosing and post-chlorination before reaching consumers. Drinking water undergoes microbiological and chemical controls in addition to evaluation of organic pollutants. Whilst chlorination remains the standard in Cyprus, other countries whose main drinking water source is groundwater ensure quality through high-quality distribution networks and maintenance of biostable water through biofilms that prevent pathogenic microbial growth.

Methodology and findings

In collaboration with EOAL (The District Local Government Organisation of Larnaca), researchers collected pipe and water samples from sites where leakages were detected and from scheduled network upgrade works. Samples were photographed and identified in situ before being transported to the University of Nicosia laboratory. A water filter from a household in Nicosia was also evaluated.

Samples consisted of asbestos pipes, plastic pipes, metal connectors and a household filter. Photographic evaluation and ATP (adenosine triphosphate) measurements were conducted on swabs obtained from the samples. Additional samples were collected for DNA analysis and stored at 4°C and -20°C.

Sample collection in situ, facilitated by the utility organisation, proved challenging in maintaining samples free from soil contamination. In many cases, pipes had been replaced before sample collection, preventing further analyses. Nonetheless, results show microbial presence in all samples examined, with consistently higher levels in metal connectors (joints) compared to plastic pipes.

Future research

The next steps in research would involve expanding to additional areas and conducting bacterial species profiling in different environments.

Contact information

For further information, contact Professor Edna Yamasaki, School of Life and Health Sciences, Department of Health Sciences:

• Tel: 22 841743
• Email: yamasaki.e@unic.ac.cy