School of Engineering


Cara Wray

Cara is one of our current STREAM researchers.

My PhD project focuses on the relationship between chlorine disinfection and bacteria in water treatment plants. Coliform bacteria are used by the water industry as an indicator of faecal contamination and organisms potentially harmful to human health.

They are an extremely important group of bacteria to monitor as they have the greatest capacity for causing illness in humans and causing repercussions for the water company if not successfully removed by the treatment process.

Chlorine is the most widely used method of water disinfection globally as it is both cheap and highly effective.

My research aims to investigate the possible ways in which coliforms could survive chlorine disinfection in water treatment plants – whether through genetic resistance, shielding by particles, shielding within biofilms or any other process.

Bacteria that develop resistance to chlorine could compromise water quality and put the public at risk of infection with microbial contaminants.

The emergence of chlorine resistance could also explain situations where water treatment plants detect coliforms in their final water despite seemingly working to satisfactory standards.

My academic background is mainly in microbiology and molecular biology. I graduated from the University of Birmingham with a BSc in Human Biology, where my final year project focused on antibiotic resistance plasmids in E.coli.

This project greatly interested me in microbiology and resistance mechanisms, leading me to undertake an MSc in Clinical Microbiology at the University of Nottingham. After graduating in 2013, I began working as a microbiology quality analyst for Severn Trent.

This job involved analysing drinking water samples for the presence of coliforms and other indictor organisms and developed my interest in the microbiology of water treatment processes.

The STREAM program was the perfect opportunity to combine my academic interest in resistance with the more practical concerns of the water industry.

A huge benefit of STREAM is that it allows you to consider problems and questions from different viewpoints as you gain advice and experience from both academia and industry.