Dr Louise Fletcher

Dr Louise Fletcher


  • Programme Leader MSc Environmental Engineering and Project Management

Research interests

My research interests encompass a range of different areas within the fields of microbiology and aerobiology. At present my interests lie primarily in the field of environmental microbiology with particular emphasis on the generation and control of pathogens in indoor and outdoor environments. I am also interested in the aerobiological aspects of waste treatment and disposal with the focus being the generation, dispersal and control of bacterial and fungal pathogens during composting.

 Current Research Projects:

BEFWAM: Bioenergy, Fertiliser and Clean Water from Invasive Aquatic Macrophytes, Funder BBSRC, £1.7 million, 2019-2022


The project is a collaboration between University of Leeds, The Centre for research in energy and energy conservation (CREEC) Uganda, The Institute of Chemical Technology, Mumbai, India and Visva-Bharati University India. The project focuses on utilising invasive aquatic macrophytes such as water hyacinth in combination with nutrient rich waste and immobilised microbial systems to maximise the production of biogas whilst generating clean water and recovering nutrients in low income communities, by developing innovative biotechnology solutions that promote resource efficiency and long-term sustainable services.

Completed Research Projects:

EU LIFE project – CONDENSE – The Condense Managing System – Production of Novel Fertilisers from Manure and Olive Mill Wastewater

The research involves evaluating the performance of fertilisers made from organic wastes using pot and field trials on a range of crops appropriate to Northern Europe and determining whether the fertiliser will be accepted as a replacement for inorganic fertilisers by farmers. The nutrient levels of the fertilisers will be enhanced through composting and solar drying. The LIFE project is being led by Greek partners who have a particular problem with wastes from farm animals and the processing of olives. The intention is to produce an organic fertiliser with enhanced levels of N, P and K which will compete with inorganic fertilisers currently on the market. The fertiliser must not only have the nutrient levels required by the farmers but it also be in a form which is acceptable to farmers for application to conventional crops.

EU FP7 Project – FERTIPLUS – Reducing Mineral fertiliser and Agro-chemicals by Recycling Treated Organic Waste as Compost and Bio-char products.

The research will identify urban and farm organic wastes that can be used to recycle nutrients into agriculture as biochar, compost or combinations of them. It will assess and use this potential and contribute to sustainable crop production and soil productivity and quality across regions in Europe. It will demonstrate effective innovative processing and application of biochar and compost while ensuring safety for soil organisms, the environment and human health throughout the food chain as far as potential mineral and organic contaminants are concerned.

Sniffer - Understanding Biofilter Performance and Determining Emission Concentrations ubnder Operational Conditions.

This research project was commissioned by Sniffer on behalf of the UK environmental agencies and was carried out by a team led by myself at the University of Leeds in partnership with Odournet UK. The overall objective was to determine the extent to which abatement methods incorporating either open or enclosed biofilters reduce both bioaerosols and odour enmissions from enclosed biowaste treatement operations. A total of 8 enclosed biowaste sites have been sampled and sim,ultaneous odour and bioaerosol samples collected from the inlets and outlets of the biofilters. Samples have been analysed fro odour, hydrogen sulphide, ammonia, VOCs, Aspergillus fumigatus, total bacteria and gram negative bacteria. The results will be used to determine the performance of the different abatement systems and impact of key design, operating and maintenance parameters on performance. The information will then be used to provide the UK environmental agencies with a recommendation for the Best Available Technology (BAT) for biofilters.

British Council New Partnerships Grant

Funding was obtained to facilitate the establishment of new links and collaborations between the School of Civil Engineering and other academics outside the UK. The other institutions involved were The Centre for Global Safe Water, Emory University, Atlanta, USA, Universidad del Valle, Cali, Columbia and the Faculties of Chemical Engineering and Engineering at the Universidad Autónoma de Yucatán, Mexico. The focus of the research project was theIdentification of Norovirus in wastewater samples from natural wastewater treatment systems.  

DEFRA - New Technologies Demonstrator Programme

Two projects funded by DEFRA totalling £300,000 to idependently monitor and provide data on the economic, social and environmental viability of two innovative waste treatment technologies providing an alternative to landfill. It is hoped that the results will provide key decision makers with the information about the realities of implementing such technologies and allow them to make informed decisions about the future of biodegradable waste treatment in the UK.

Department of Health - Design and Performance of Isolation Rooms

This project focuses on the design and performance of isolation rooms for hospital nvironments. The study involves infection risk modeling, CFD modeling of isolation room airflows, experimental studies comparing tracer techniques to bioaerosols in the Leeds aerobiology chamber and experimental studies in full scale mock-up rooms to assess steadt state and transient behavious against particles and tracer gases. Applications include the assessment of the PPVL isolation room which i9s discribed in HBN 4 suupliment 1, and is now the recommended design for most isolation rooms in UK hospitals

KTP Project - Development of Ultraviolet Sterilisation Products for the Ventilation Industry

This £120,000 project in partnership with Mansfield Pollard Ltd aims to develop a state-of-the-art range of industry leading 'airside' untraviolet starilisation prducts for the H&V industry and establish an R&D function.

EPSRC - The Use of Small Negative Air Ions to Disinfect Acinetobacter spp. and other Airborne Pathogens in Hospital Buildings

This £280,000 project followed on from a successful pilot study in the intensive care unit at St James's Hospital, Leeds , which demonstrated the potential for negative ionisers to be used to reduce the transmission of airborne infection in hospitals. The study involved complementary experimental and CFD modelling work to understand the physical and biological processes that occur when airborne microorganisms are exposed to negative ions. The study aimed to investigate these fundamental processes to gain an understanding of the potential for using ionisers in tackling hospital-acquired infection. The project examined how and where ionisers could be used, producing results of great value to those involved with infection control in hospitals.

EPSRC - Ultraviolet Disinfection of Mycobacterium Tuberculosis and other airborne pathogens in hospital buildings

This £219,000 project followed on from an initial clinical pilot study sponsored by NHS Estates. It investigated in detail the aerobiology associated with the transmission of tuberculosis and other infections in hospital buildings. In particular, the project studied the photobiology associated with ultraviolet germicidal irradiation and sought to optimise the air disinfection capability of ultraviolet germicidal lamps through experimental work and CFD analysis. 

<h4>Research projects</h4> <p>Any research projects I'm currently working on will be listed below. Our list of all <a href="https://eps.leeds.ac.uk/dir/research-projects">research projects</a> allows you to view and search the full list of projects in the faculty.</p>


  • BSc (Hons) in Geography, Huddersfield Polytechnic, 1989
  • MSc Environmental Pollution Control, University of Leeds, 1990
  • PhD

Student education

I currently teach a range of undergraduate and postgraduate modules that cover the areas of sustainability, environmental impact, water quality, aerobiology and waste management. Alongside this I am also involved in undergraduate professional/transferable skills development.

Research groups and institutes

  • Water, Public Health and Environmental Engineering
  • Cities, Infrastructure and Energy
<h4>Postgraduate research opportunities</h4> <p>We welcome enquiries from motivated and qualified applicants from all around the world who are interested in PhD study. Our <a href="https://phd.leeds.ac.uk">research opportunities</a> allow you to search for projects and scholarships.</p>