Digitally enabling the circular economy in Sub-Saharan Africa

How the Wastebase app is helping Mozambique’s Repensar Environmental Cooperative track plastic waste

9 min readMay 7, 2021

“When I stood with my feet on the river bed, the water was full of plastic. Being light, the bottles had got caught up in the mangrove. From the ground to my hip was all plastic bottles. At that moment I realised that plastic was a true challenge to our life on this planet.

Carlos Serra, Repensar Mozambique

Oceans of plastic

Carlos Serra, a lawyer and environmental activist working in Maputo, Mozambique, was standing in the Matola River when he was overcome by the scale of the plastic problem in his country. One year later, in 2014, he set up the Repensar Environmental Education Cooperative as a means of clearing the glass bottles that littered the city. Repensar means ‘rethink’ in Portuguese, the official language of Mozambique.

Mozambique is one of the poorest countries in the world, measured by per-capita GDP. After a prolonged period of war ended in the early 90s, the country experienced over a decade of rapid but unequal economic growth. In recent years it has struggled to recover from a huge corruption scandal, falling natural resource prices, and a rebellion in the north of the country. The capital, Maputo, in the far south of the country, has expanded over the last twenty years to become an urban area home to nearly four million people.

Map showing Mozambique and its major rivers
Major rivers of Mozambique

The local culture of ‘txilanço’ (‘drinking with friends in a scenic spot’) had turned Maputo’s long sandy beaches into minefields of discarded beer bottles. Repensar mobilized large numbers of volunteers to perform intensive cleanups coupled with public information events. Crucially, they counted and categorized the bottles they collected. After cleaning up the bottles, they summarized their data and took it to the city council. The information persuaded the council to improve the availability of waste disposal points near beaches, as well as alter the frequency and routing of waste collection in these areas over weekends.

This commitment to driving change rather than just picking up the mess is reflected in the organisation’s full name: ‘Rethink Environmental Education Cooperative.’ Rethinking begins with understanding, and it was Carlos’s investigation into the problem of glass waste that led him to his moment in the Matola River, one of the main rivers of the greater Maputo area. He had been active as an individual in environmental issues for some ten years, mainly focused on clearing up this glass waste from his native city.

“We knew that wherever there is Txilanço, some people are drinking beer, and many others are drinking water or soft drinks — so we expected to find just as many plastic bottles as glass — but we weren’t. Where was the plastic going?

We started to hunt it down, and realised that much of it was ending up in waterways and from there slowly being drawn towards the sea. Following the Matola we came across a sight that I will never forget. A mangrove swamp, positioned at the joining of two waterways. The plastic bottles, being light, got caught up in the mangrove and accumulated over time.”

At the same time, Repensar had been following the work of the Ellen McArthur Foundation on a circular economy for plastic. Repensar shifted their focus to tackling the plastic problem.

Map showing mangroves of Maputo, Mozambique. There are several large areas of mangrove around the waterways flowing into Maputo Bay.
Mangroves of Maputo (Source: The Plan Journal)

Leveraging local waste audits through Wastebase

Fast-forward to 2020 and was looking for partner organizations to lead data curation in Southern and Eastern Africa. aims to create a cloud platform to connect everyone who can help reduce plastic waste entering our planet’s environment.

In 2020, launched Wastebase. A social impact project, Wastebase (currently in beta) is a digital platform for crowdsourcing structured information about plastic waste. With a simple app designed for use with basic smartphone technology and in real life conditions, anyone can scan and log a plastic bottle using the product barcode. Where the barcode has been damaged, the bottle can still be recorded with a quick search for the same item in the Wastebase database. This data can be accessed and used by activists, campaigners and concerned citizens across the globe.’s founder, Cameron Smith, was searching for potential Wastebase Data Partners. “Our Data Partners are essential to getting good quality data. We were looking for NGOs [non-governmental organisations] already active in the zero waste/circular economy space in their country. Typically, these NGOs are part of the Break Free From Plastic (BFFP) movement.” BFFP performs a comprehensive global plastic audit, once a year.

Cameron started to talk to some people he knew in Mozambique.

One name came up again and again: Carlos Serra. I arranged a meeting and Carlos’ plainspoken sincerity came across straightaway. I explained the idea of Wastebase and Carlos immediately pointed out that Repensar had several teams performing regular waste audits at key points across the greater Maputo area, but that data recording and collation was manual and rather time-consuming”.

Auditing plastic waste in Maputo

Repensar has carried out regular audits of waste since 2015. They target high-profile locations around Maputo where the waste statistics will be significant enough to turn the heads of decision makers. Early on, Carlos recognised the importance of public waste audits as a means of engaging local people in the ‘rethink’ approach. For each audit, large numbers of volunteers turn up in Repensar t-shirts to collect waste within a set time period. Each item is manually logged on paper, while volunteers chat to passers-by about what they are doing.

After the audit, some of the collected waste is used by Repensar itself for public display projects, some is delivered to professional waste pickers, and the remainder is deposited in the Municipal waste collection system.

Each audit aims to achieve four objectives:

  • to leave the target area, typically a public space, clean and tidy
  • to raise awareness, through the large number of volunteers involved and engagement with local residents
  • to sort and classify the waste, identifying specific types of materials, in particular:

a) potentially recyclable materials such as glass, paper and plastic

b) hazardous materials such as discarded batteries

c) waste which could be diverted from the municipal solid waste (MSW) collection chain; principally food waste and organic matter (Maputo has a lot of urban trees)

  • to identify the brands responsible for the waste

The locations include popular beaches and leisure locations, major schools, and busy office areas.

Blackboard showing handdrawn table with names assigned to different areas.
Repensar waste audit planning board (unwaste/Cameron Smith)
Photograph of man leaning over computer and two seated people looking at computer.
Training on the Wastebase data portal, at the Repensar office (Repensar/Adelson Mutemba)

Becoming a Wastebase Data Partner

6 Repensar activists completed their Wastebase training over March and April 2021. The training involved both field-based practical training and classroom learning in Repensar’s office (filled to the brim with classified waste samples and tools). Classroom time is a mix of theory (understanding types of plastic, for example) and practice to log, extract and visualise data in Wastebase. By the final session, a team of 8 activists supported by 20 part-time volunteers was able to collect, sort and log over 2,800 bottles in a 2 and a half hour session.

All the training used existing hardware, Repensar’s mid-range PCs and volunteers’ own Android phones. These were typically lower-end smartphones with around 1Gb of RAM. Repensar’s Macaneta coordinator Adelson Mutemba said, “I use my phone for everything and in fact it probably does have too many apps installed. I was a bit surprised that Wastebase worked first time”.

As part of the field training, the team collected and recorded over 4,000 bottles from the Greater Maputo area. Wastebase allowed us to immediately build up a picture of the most commonly discarded products by brand.

Photograph showing two men scanning plastic bottles with a smarthphone in an open outside area.
Image: scanning bottles in a Maputo park during field training (Repensar/Bruno Vaz)

Interestingly, while the most prominent brand was Coca-Cola, second place went to “Fizz”, a local brand of flavoured soft-drinks. Even the ‘leading’ mineral water brand, Água de Namaacha (a local brand) only took seventh place, after six soft-drinks brands.

Pie chart showing coloured segments. Key shows that different colours relate to different brands of drink.
Distribution of brands contributing to waste detected in Mozambique (Source:

Making data work harder: how Wastebase helps

Wastebase offers consistent and hassle-free recording of data about abandoned plastic bottles in near-real-time. The app is designed for use at the waste audit site. Unlike paper-based audits, there is no need for follow-up paperwork or data input at a desk. Data is immediately visualised on a map and in simple charts, making it much easier to demonstrate the problem.

“It was incredibly satisfying to log a bottle and see the ‘My Bottles’ counter on the app tick up,” said Josela Capassura, Repensar’s projects coordinator. Josela managed 33 scans in her first 15 minutes of field practice. One month later, she scanned over 1,400 bottles in a single session, working with a colleague who grouped and moved the bottles as she recorded them in the app. “It’s so much quicker and easier when we can focus on collecting the PET waste, and get the detailed information out of the system when we’re back in the office.

Wastebase app screens showing 1) bottle input options 2) manual product search 3) identification by barcode (

Wastebase identifies every beverage product by its unique GTIN barcode. Once a product has been scanned, users can add additional information such as volume, brand or distributor. This data is then available for any future scans of the same product and for quick, filtered searches. For example, a researcher could search for all products made by Coca-Cola, a US Company, to produce a breakdown of how many were found, where and under what sub-brand.

Pie chart separated into coloured segments. Title says ‘Country: Mozambique.’ Key to colours shows different manufacturer names such as US: Coca-cola.
Distribution of brand owners contributing to waste detected in Mozambique (Source:

It’s important that the app works in any setting,” said Cameron. “Obviously, discarded bottles can be dirty or damaged, and people collecting the waste might be wearing gloves or only have one spare hand. We’ve been testing it ‘on site’ as much as possible.”

As part of the Repensar training, the team found several bottles that had only a scrap of the label remaining. “We were able to identify the bottle by matching the distinctive shape with other bottles we’d found. We were then able to search for that item and log the damaged bottles with a few clicks.”

Three plastic bottles of the same size and brand. One has a label, the others are matched by the shape and patterning of the bottle . They all have diagonal markings on the lower half of the bottle body.
Image: three bottles of the same size and brand. One has a label, the others are matched by the shape and patterning of the bottle: notice the characteristic diagonal markings on the lower half of the bottle body. (unwaste/Cameron Smith)

Wastebase for research, reporting and campaigning

From the beginning, the team knew that, to influence the most powerful players in the plastics industry, Wastebase had to help leverage data as evidence for the many activists and campaigning NGOs in the zero waste and circular economy movements.

“Local waste audits are important, but to really effect change, we need to supercharge that data by collating and visualizing it in a way that makes it easy to tell the story of what’s happening in our environment. We’ve been working with NGOs to understand what they need from the data and how they want to use it. Simple visualisation is vital, alongside easy filtering and reporting options.

Cameron Smith,

As a result, Wastebase includes a function to curate a structured database of products, their brands, and the corporate entities which own and distribute those brands. This helps NGOs identify domestic and international actors to engage with. The NGO can build up a repository of evidence to use in different formats and for different purposes, whether that is raising awareness, direct pressure on industry or making the case for potential solutions.

The Wastebase Reporting and Data Visualization tools allow the NGO reach its target audience, such as the easy export of data for submission to BFFP’s global brand audit database.

What’s next for Repensar and Wastebase

Now they are fully trained Wastebase Data Partners, Repensar are keen to make the most of the platform. They’ve scheduled regular weekly audits in three key locations around the Maputo area, and are preparing a graphic report for Maputo City Council. In the medium term, they’ll be developing an outreach program for school leavers.

It’s really important that we get young people thinking about waste in a different way,” said Carlos. “By changing attitudes to waste, we have the power to change our whole approach to plastics and improve the environment for the next generation.”

Find out more

Repensar Mozambique


Brand Audit toolkit (Break Free from Plastic)

How GTIN barcodes work (GS1)

If you would like to get involved or become a Wastebase Data Partner, let us know at



unwaste aims to create a cloud platform to connect everyone who can help reduce plastic waste entering our planet’s environment.