“You can’t build sustainably if you’re breaking down internally.” — Murendeni Mafumo

In a country where millions still live without access to clean drinking water, one entrepreneur is proving that innovation, community, and purpose can create real, lasting change. Murendeni Mafumo, founder of Kusini Water, joined Mashstartup to share the full story behind building a life-saving social enterprise — from the early prototype phase to scaling a solution that now produces millions of litres of clean water across South Africa.

This episode is a deep dive into what it really takes to build a business that changes lives — and what it means to be a social entrepreneur in South Africa today.

💡 From Idea to Impact: The Kusini Water Story

Murendeni didn’t start out as a founder — he was a trained chemist and worked in water management for the City of Cape Town and later, the City of Johannesburg. But the more he saw how poorly infrastructure served rural and peri-urban communities, the clearer the gap became: people needed access to clean water, and the current system wasn’t going to deliver it.

That’s where Kusini Water was born.

Combining macadamia nut shells and nanotechnology, Murendeni developed a sustainable, low-cost water filtration system. The idea was simple: use waste products and smart design to deliver clean water to communities that need it most.

Fast forward a few years, and Kusini is now:

  • Producing over 5 million litres of water a month

  • Operating water kiosks across three provinces

  • Empowering local entrepreneurs as “water champions”

  • Partnering with organisations like FNB, Edge Growth, and the U.S. Embassy

🔍 What We Talk About in This Episode

In our conversation, we go beyond the headlines and unpack what it really takes to build a mission-driven business in South Africa. Some of the key topics include:

  • The messy middle of prototyping — how Murendeni iterated his product with limited resources and real-world testing

  • The value of grant funding — and why we need to shift how we think about capital for impact

  • Being a social entrepreneur — what it means to build with people, not just for them

  • Taking care of the founder — why emotional and mental resilience is non-negotiable for builders

🧠 A Masterclass in Purpose-Led Entrepreneurship

Murendeni’s story is more than just a case study in innovation. It’s a reminder that the best solutions are born out of deep understanding, lived experience, and community-rooted thinking. His approach to building Kusini Water is proof that Africa’s most pressing problems can — and should — be solved by African entrepreneurs.

But he also reminds us of something just as important: you can’t pour from an empty cup. Whether you’re building a social enterprise or a tech startup, caring for your personal purpose and mental health is just as important as scaling your solution.

More on Kusini Water:
Visit www.kusiniwater.co.za to learn about their mission, technology, and how you can support their work.