Food from waste

  • February 8, 2013
Food from waste

Luca di Mario is doing research into how sewage can be used in agriculture in safe and cost effective ways.

How can we boost agricultural output in an affordable and safe way and benefit urban and peripheral communities in developing countries?

For Luca Di Mario [2009], water sanitation is the key. He is doing his PhD at the Centre for Sustainable Development (Engineering Department) and is looking to find sustainable business models for scaling up resource recovery from solid waste and waste water so that it can be used in agriculture in developing countries. That includes assessing the benefits and risks for public health and the environment. “If you use waste in agriculture it can be a win-win solution, but you have to make sure it is safe for people and the environment. Waste/waste water contains nasty things such as pathogens or heavy metals and we do not want to offset any benefits we want to create,” says Luca.

The project aims to give farmers access to safe resources from waste such as water, nutrients and energy which are cheaper than traditional fertilisers; ensure the ecology of rivers is maintained; and help people to see sewage as a resource and so boost interest in investing in sanitation.

But although engineering is important, there are wider issues involved which present the main challenges. “The big challenge,” says Luca, “is to make the process profitable for scaling up and to create a sustainable impact.” That is why his research project is doing fieldwork in a range of areas where different issues present, including water scarcity. “We are trying to understand which business model might work in which region so that we can expand them and to investigate the social, legal and environmental impact, both positive and negative,” he adds.

Early days

Luca has always had a broad range of interests, encompassing politics, science and internationalism. He was born in a small town near Rome. His mother was an English teacher at his school which put him under extra pressure to study hard and behave well. So much so that he rebelled as a teenager and refused to learn any more English – ironically, given that soon after he became heavily involved in international exchange programmes.

Luca had broad interests at secondary school, including literature and politics, but his main focus was on science and maths. He did voluntary work on environmental issues which he was passionate about from an early age, partly due to his mother’s green concerns, but then got involved in intercultural exchanges in Europe. He did his first one while he was still at school after taking part in a student version of the European Parliament.

He so enjoyed the exchange that he ended up doing 16 more and travelled to countries ranging from Bulgaria to Sweden meeting fellow Europeans and also young people from the Middle East and North Africa. “It was then that I understood the importance of speaking languages and of multiculturalism,” he says. “The exchanges really shaped my way of thinking and made me appreciate different cultures and gave me a broader perspective.”

Luca also hosted an exchange of around 40 people with his friends. It was his first experience of project management and he had a budget of 25,000 Euros. The exchange involved videos on issues such as gay rights and gender. The committee that organised the exchange is now an association and is still going strong.


Luca did a degree in engineering at the Universita’ La Sapienza in Rome, but he was not sure even on his first day whether he was going to do that or political science. He decided that he could further his interest in politics himself so opted for civil and environmental engineering. He did his dissertation on water distribution systems and how to avoid leakages, but wasn’t sure what he wanted to do when it ended. The obvious next step on leaving university was to get a job with a local water distribution company, but he wanted to broaden his outlook and do a job which would have “impact”.

He spoke to one of his professors and he invited Luca on an expedition to a refugee camp in the Sahara to build a water distribution system for a hospital and implement a pilot project involving irrigation powered by solar energy. Luca was there for three months, sleeping in a mud house in the desert of southern Algeria. He really enjoyed being there, particularly meeting the people of the ex-Spanish colony of Western Sahara. “It changed my life,” he says.

Luca returned to Italy and applied for a masters course in environmental engineering at Imperial College in London. He wanted to do something that was more practical. “I was aware from my time in Africa of the impact of engineering on health and realised that sanitation is a vital issue for developing countries,” he says.

His dissertation was on a water treatment project in rural and slum communities in Nepal. It involved a lot of fieldwork and a whole range of different areas, from technical and environmental issues to social and political ones.

It was his awareness that many of the problems demanded a broader response which led Luca to apply for an MPhil in Engineering for Sustainable Development at the University of Cambridge where he focused mainly on social, economic and political issues. He got a Gates Cambridge Scholarship for the MPhil and applied to do a PhD.

However, he decided he was losing touch with what was going on the ground so he applied for a consultancy post with a UN agency – the International Fund for Agricultural Development in Rome. He was advised by his manager to travel as much as he could with the job and so he visited India, Bangladesh, Sri Lanka and Ethiopia.

He spent three and a half months in Ethiopia helping with grants and loans and monitoring the implementation of several small-scale irrigation schemes. “It was more about capacity building with local communities than engineering,” he says. “It was about investigating the long-term sustainability of the project – would the people who lived there benefit from it in 10 years’ time.” His work involved liaising with water user associations and other local institutions and also with the Ethiopian government.


Luca spent a year and a half working for the UN agency and feels he learnt a lot. “I was managing research grants and was in touch with international research institutions for water, all of which I am now doing for my PhD,” he says.

At the end of his stint at the agency Luca worked on a $200,000 project funded by the UK Government’s Department for International Development (DFID) whose aim was to inject innovation into the procedures of the International Fund for Agricultural Development by bringing together younger and more senior consultants working on water for agriculture issues. The project is now being implemented in several countries, including Ethiopia, Burkina Faso and Senegal.

Luca returned to Cambridge to do his PhD which involves working with six international partners on a $2m project with fieldwork in four countries – India, Vietnam, Uganda and Peru.

The project is funded by the Swiss Development and Cooperation agency and has a range of partners, including the International Water Management Institute, the World Health Organization, the Swiss Institute for Aquatic Research and the Swiss Institute for Tropical Hygiene.

Luca says the work he is doing is very fulfilling as it brings together all his passions, from engineering to politics and multiculturalism. “It is truly interdisciplinary,” he says, “as these issues encompass so many different areas.”

Picture credit: and africa.

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