Ashley Murray

Wastewater Engineer

Emerging Explorer


Photograph by Chris Owen

Photo: Ashley Murray

Photograph by Matthew Muspratt

At any moment, half of the world’s hospital beds are filled with people suffering from water-related diseases. Each year, two million of them will die. Why? Every morning, more than 2.5 billion wake up with no access to basic sanitation.

Ashley Murray is working to revolutionize the way the world thinks about waste, but rather than pointing to public health or the environment, she’s motivating governments and the sanitation sector with a persuasive new argument: dollars and cents.

It’s not that she’s insensitive to people and the planet. She makes her home in urban Ghana where, as she describes, “Any surface water is an open sewage stream. It’s hard to overstate the enormous health and environmental impacts of inadequate sanitation.” Her unique solution is not to get rid of wastewater and fecal sludge, but to value them.

“Reusing wastewater has always been promoted for environmental reasons,” Murray explains. “But environmental protection is never going to be a compelling enough reason for resource-strapped governments. With so many pressing urban challenges, they see wastewater reuse as an added burden with no direct or immediate value. Why pay to treat water before throwing it out when they can just throw it out for ‘free?’ Of course, that doesn’t take into account all of the environmental and health hazards that result from not properly managing waste. So I started thinking outside the box. I knew most government decisions always come down to money. And I realized I could make a very compelling argument for reuse based on economics, proving it could actually contribute to the sanitation sector.”

In the past, financing waste management has depended on making individual households pay user fees. But in low income areas, families simply don’t have the money. The result? A bankrupt system. Murray says sanitation’s user-fee model is broken. Instead of making households pay, she wants to capture the inherent economic value of waste itself, and use the profits to help pay for sanitation. She points out that “waste contains all kinds of resources—nutrients that can be used in agriculture and aquaculture, embodied energy, and all kinds of non-potable uses for the water itself.”

To prove it, Murray founded Waste Enterprisers. The company sets up, owns, and operates waste-based businesses. Each business relies on human waste as its primary input, makes a profit from reusing it, then ploughs a portion of those profits back into providing sanitation for the poor. “What’s novel about our approach,” she stresses, “is that we show how waste can bring money back into the sanitation sector. That’s why I registered Waste Enterprisers as a for-profit company. I wanted to highlight that sanitation is a business and that it can be profitable.”

Just look at the commercial fish farm operated and maintained by the group in one of Ghana’s government-owned wastewater treatment plants. Catfish are stocked and harvested in the last phase of the facility’s waste stabilization pond system. “This plant never had a revenue stream because it serves a community that doesn’t pay user fees,” Murray notes. “As a result, maintenance was always limited and haphazard. Our fish farm supplies a new, reliable revenue source that will ultimately pay for the full-time groundskeeper we’ve hired. When you’re dealing with low-cost sanitation systems, it doesn’t take a lot of money to make a significant impact on the maintenance and overall performance of a facility.” Nutrients in the wastewater support the fish, so no external food is added. Other inputs and fish density are also carefully limited to avoid compromising water quality or degrading the environment.

Waste Enterprisers is also collaborating with a consortium of research organizations to test using fecal sludge as an industrial fuel. Technical and economic feasibility will be assessed at a demonstration project in a Senegalese cement plant where sludge is co-incinerated with conventional fuels. Murray predicts that energy embodied in the dry solids portion of fecal sludge can be equivalent to coal; in other industries it would replace oil or residual fuel oil. “It’s quite possible fecal sludge can be incorporated in cement plants with no changes or additions to existing infrastructure,” she says. “It shouldn’t have detrimental affects on plant emissions, and since ash left after burning can be incorporated into the cement product, it’s a completely closed-loop, zero-waste management solution.”

Next Waste Enterprisers will focus on cutting-edge technologies such as using fecal sludge to make bio-diesel and other new industrial fuels. “Our businesses are out to prove that sanitation can be profitable. But their success is just the means to an end,” Murray reminds. “The real goal is improving basic sanitation, health, and environmental conditions for some of the world’s poorest populations. If I can prove this is a viable business model, I hope copycats spring up everywhere. I want to catalyze the use of our ideas in cities all across Africa.”

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In Their Words

“I don’t think of waste as something to get rid of, but as a resource with real economic value. Profits made from reusing waste could transform sanitation and health around the world.”

—Ashley Murray


Listen to Ashley Murray

Hear an interview with Murray on National Geographic Weekend.

  • 00:06:00 Ashley Murray

    National Geographic Emerging Explorer Ashley Murray tells Boyd about her groundbreaking work in Ghana, transforming a crude human waste treatment plant into a profitable fish farming business while also giving the Ghanaian people access to a cleaner way of life.

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