MalawiDrop is an affordable household water treatment system that delivers safe drinking water directly at the point of use for off-grid rural communities. It was co-founded by Tadala Mtimuni, a chemical engineer. The device incorporates a refillable chlorinated resin cartridge that enables controlled chlorine release for effective disinfection, removing the need for complicated manual dosing and making water treatment simpler and more reliable for households.
In Malawi, access to treated piped water cannot be taken for granted.
Even in semi-urban areas, households regularly rely on wells or surface water sources that must be treated before use.
Tadala has seen the water access gap up close.
“Even as I speak, there are people just five kilometres from where I live who must collect water from wells or rivers,” she explains.
These realities inspired her to focus her engineering research on improving water treatment solutions for underserved communities.
Although chlorine is widely recognised as effective for sterilising water in rural Malawi, safe dosing remains complex and for many households, especially where literacy levels are low, consistent treatment is difficult to maintain at home.
Liquid chlorine requires measuring, testing strips and consistent supply chains.
Over-dosing affects taste and health, while under-dosing leaves pathogens behind.
Tadala beams: “I didn’t expect my work to leave the lab and go into communities. I was experimenting on artificial water at first, contaminating it myself for testing. To see it now moving beyond research and into real households is something I’m very proud of.”
She is now shortlisted for the Royal Academy of Engineering 2026 Africa Prize as one of the 16 innovators across 11 African countries who will compete for a share of £85 000 (about K153 million) Africa Prize fund.
Shortlisted innovations and entrepreneurs from Ghana, Kenya, Lesotho, Malawi, Niger, Nigeria, Rwanda, Senegal, South Africa, Tanzania, Zambia have each been selected for their solutions to critical environmental, educational and health challenges in their communities.
In a press release on Wednesday, the academy said Lesotho and Niger based innovators shortlisted for the first time after a record number of applications from more than 30 countries.
According to the statement, The Africa Prize, which is partly funded by the UK’s Department for Science, Innovation and Technology, is the continent’s largest prize dedicated to stimulating, celebrating and rewarding engineering innovation and entrepreneurship across sub-Saharan Africa.
It further said the innovators will enter an eight-month programme of training, mentoring and networking opportunities ahead of the final in October.
This year’s shortlist features innovators located across 11 African countries, with products ranging from AI-powered maternal, cardiac health tools and mobile dialysis technologies to digital education for biomedical and coding skills and smart public transport platforms.
Other innovations include solutions to sustainability challenges, such as renewable energy systems for off-grid communities and hospitals, smart agritech platforms, low-cost clean water supply and waste management systems.
As part of the prize, they will also receive expert business, technical and sector-specific engineering mentoring, alongside access to the Academy’s extensive network of engineers and business leaders across the UK and Africa.
The statement said the winner will receive £50 000 (about K90 m), while the three runners up will each be awarded £10 000 (about K8 m).
Since its inception in 2014, the prize has supported 165 businesses from 22 countries that employ more than 40000 people and benefit more than 11 million people through their innovative products and services.
The innovation
Tadala began developing her innovation during her undergraduate studies in 2018.
What started as a prototype funded by a small government grant evolved into her master’s research in chemical engineering at Stellenbosch University in South Africa, where she focused on water treatment systems.
MalawiDrop consists of two stacked buckets connected by a refillable cartridge containing a chlorinated Merrifield resin.
As untreated water flows from the top bucket to the bottom, the resin releases a consistent, pre-determined dose of chlorine that treats the water in seconds.
Laboratory testing and modelling indicate the system can inactivate over 99.99 percent of pathogens in less than a second per litre.
The innovation relies on a combination of chemistry and engineering.
Tadala and her team impregnate a merrifield resin with chlorine using sodium dichloroisocyanurate (NaDCC), enabling a stable and consistent release that avoids the hazards of alternative halogens and the inconsistencies of liquid dosing.
Cartridges can last between six months and two years depending on usage and are refillable rather than disposable.
To support access and ongoing maintenance, the team plans to distribute MalawiDrop through community “water champions” who run demonstrations and trials, alongside local water kiosks where households can collect the device and return for cartridge refills.
Kiosks are designed to work like familiar mobile money kiosks, creating a convenient local touchpoint for users and a practical route for refills, which cost around £7.
MalawiDrop is led by a multidisciplinary team, including co-founder Ananias Cyrus Zulu and specialists in production and operations.
Alongside scaling across Malawi and Rwanda, the team plans to expand water workshops and regional distribution points to strengthen access and after sales refills.
They are also developing an enhanced version with smart sensors to monitor cartridge status remotely, strengthening quality control and enabling scale through a grant partnership with Rwanda.
Across sub-Saharan Africa, more than 400 million people lack access to safe drinking water, with rural communities often facing outbreaks of cholera and other waterborne diseases, especially during rainy seasons or floods.
MalawiDrop is a new automatic water treatment device designed for off-grid household use, making at-home water purification both cheaper and more accessible.
Using a refillable chlorinated resin cartridge, the system releases controlled doses of chlorine as water flows through, eliminating guesswork and reducing health risks from over or under dosing.
MalawiDrop is now scaling production across Malawi and Rwanda, with plans to reach thousands of households in off-grid communities in sub-Saharan Africa.
Africa Prize support would accelerate manufacturing capacity, expand distribution and establish additional workshops across Malawi’s three regions. Africaprize.raeng.org.uk/ Caroline Somanje.
