Alumnus Masaka Maganga (2004/2006) from Tanzania and alumnus Nirajan Dhakal (2009/2011) from Nepal, currently Lecturer at IHE Delft, are working together in designing and studying the feasibility of rainwater harvesting technology in Tanzania. The feasibility study project “Mbinguni Maji (Water from Heaven/Hemel (s) water®)” receives support from the Dutch Government “Partners for Water” programme. The project started on 1 January 2019 and will end by 31 December 2019.
Supply of reliable, affordable, and safe drinking water is a major challenge in Tanzania. The current water demand is much higher than the supply. Water borne diseases such as cholera account for half of the diseases affecting the Tanzanian population due to lack of access to safe drinking water. The untreated water has high concentrations of nutrients in it, which makes it unsafe to drink. Furthermore, there is a lack of maintenance of the network which causes leakages and contamination of the drinking water.
The situation is already critical, and the government has embarked on decentralized policy in providing clean and safe drinking water to the people. Currently, the Tanzanian government implements a new policy to have rainwater harvesting infrastructure in new buildings.
Rainwater treatment technology
The technology to treat rainwater was developed by Water Innovation Consulting. It was a first prize-winning water solution (Challenge City of the future 2016), as well as a finalist in the Herman Wijffels Innovation prize 2016 and the Water Innovation prize 2017.
The rain water from the roof is first collected in the upper tank and is treated using a Denutritor (for nutrients removal) and an ultrafiltration membrane (for bacteria and viruses removal) by gravity. The purified water as “Water from Heaven” is stored in the bottom tank, and can be used as drinking water. The closed system design prevents the evaporation of treated water and as well as the contamination of bacteria, algae etc.
The system provides enough water all year round for drinking and cooking and meets the WHO and Dutch water quality standards. Operation and maintenance of the system can be done appropriately by the owners themselves. The water is produced in a sustainable way; the technology consumes no energy nor chemicals and produces no waste streams.
In the feasibility study of this project, the partners are looking at the technical, social, economic, marketing and legal aspects of the technological solution. The outcomes will help decision-making for future pilot and demonstration projects.
Pilot and upscaling of the technology
The outcome of the feasibility study will determine if a successive pilot demonstration project in Tanzania is possible. The success of the project in both the feasibility and pilot phase will provide more business opportunities and further collaboration within the Tanzanian water and public sector.