As the sun sets over the lush fields in the Indian city of Kolkata, it suddenly dawns upon me: this is the circular economy in action. It may be a low-income, low-tech, low-scale setting, but the scene before me is an example of the circular economy as powerful as it is simple. Why? The farmers working their fields are irrigating their crops with wastewater. By just a short pipe from the neighboring Wastewater Treatment Plant, they are recycling valuable nutrients from human waste into food.

One farmer smiles and proudly tells me how his crop of salad can be sold for a high profit to nearby 5 star hotels. Here, lettuce is a cash crop. The brilliance of this simple solution isn’t lost on me, but there’s also something disturbing about untreated wastewater, possibly containing harmful bacteria, being applied to leafy greens that will end up on someone’s dinner plate.

Later, as I’m heading back to my (not five star) hotel, I remember that Jack Sim once compared human waste with fire. It can be dangerous, but brings great benefits if properly managed. The environmental and economic benefits of resource recovery from wastewater are no longer in doubt. Turning waste into a product, creating new businesses, reducing pollution and making cities more resource efficient are obvious advantages. In addition the potential of recycling an individual person’s waste can, compared to not adding any fertilizer, bring an increase in agricultural yield of US$50 per year. So how can we ensure the recycling of nutrients from toilet to table is safe?

Salad days?

Wastewater reuse must have health – both human an environmental – as the underlying objective. Using a health-based risk assessment to better manage and finance improved sanitation, is exactly what Sanitation Safety Planning (SSP) is all about. Sanitation Safety Planning is a newly launched World Health Organisation tool, which helps optimise reuse of wastewater, greywater and excreta in low-income countries. Solving sanitation though is rather complicated, as it has a long service chain with a complex combination of stakeholders.

A recent visit to Kampala in Uganda reminded me of this. Despite the challenges, Kampala is a sanitation champion with a wide range of successful initiatives. This ambitious agenda is led by the Kampala Capital City Authority together with the water utility, and includes restoring an urban wetland (for both wastewater treatment and flood protection); reusing all the sludge from the wastewater treatment plant; building public-private partnerships, including training and certification, between the city and pit latrine emptiers; creating a call center for all pit latrine emptiers to ensure better and easier services; using social media for citizens to efficiently report local issues; school sanitation clubs to raise awareness among younger generations; as well as GIS-mapping of the entire sanitation status and needs of the city.

Sanitation Safety Planning is now being implemented in Kampala as one way to bring all these projects and actors together, and to ensure safety all the way from toilet to reuse or disposal. These are the two main features of Sanitation Safety Planning: involve all the key stakeholders, and look at the entire sanitation chain. Utilities, ministries, city authorities, pit emptiers’ unions, civil society and farmers all need to work together to achieve success.

Many sanitation challenges remain, and not only in Kolkata and Kampala. But Sanitation Safety Planning can show how conquering health risks can be surprisingly easy, even in a low-income setting – especially when combining many smaller measures.

The Sustainable Development Goals (SDGs) clearly state that sanitation is more than a toilet. It’s also about everything after that: it’s about the health and safety of the pit emptier in Kampala, the farmer I spoke to in Kolkata, and the salad-eater in the 5-star hotel. Human waste provides great opportunities as a resource if managed correctly. Sanitation Safety Planning is a powerful tool to do exactly that – allowing us to move towards a circular economy, and achieving the SDGs, one safe salad at the time.

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Marie was attending a workshop in Kampala organised jointly by IWA with the Kampala Capital City Authority and GIZ, to discuss how to build strength together.