Turning black rivers clear: A community-driven solution for Indonesia’s batik sector

For centuries, batik has shaped the cultural identity and livelihoods of communities in Pekalongan, Indonesia. Yet today, the craft sits at the centre of one of the country’s most pressing water management challenges. With support from Partners for Water, Dutch and Indonesian partners are testing ways to make this heritage industry socially, environmentally and economically sustainable. Project leader Carrina Lim (The Water Agency) and technical lead Guido van Hofwegen (Resilience BV) share their ambition: building a model that batik makers can run themselves – and that can be scaled across Indonesia.

When the river turns black

In Pekalongan, the challenges are acute. Large volumes of untreated wastewater from dyeing processes, heavy use of chemicals, and extensive groundwater extraction are threatening the environment and livelihoods of the local communities.

“During parts of the year, the river literally turns black,” says Carrina. “It becomes too polluted to treat. The city can no longer use its own surface water.” With surface water unusable, batik workshops turn to groundwater. This accelerates water scarcity, land subsidence, salt intrusion and, eventually, the displacement of local communities, as the land becomes unliveable.

“The problem is not only environmental. It is also cultural and economic,” says Carrina. “Batik is part of our heritage, traditionally passed down from mothers to daughters over generations. Yet now the very practice is threatening the environment it depends on. Young people look at this sector and think: why stay? It feels like a doomsday scenario.”

The Green Batik Pekalongan pilot

The two-year Green Batik Pekalongan pilot aims to address the water pollution and availability challenges in Indonesia’s batik sector. It originated from work that Carrina and her team began in 2022, when they first explored Dutch and international solutions for Pekalongan’s wastewater challenges. “We realised quickly how sensitive the topic was,” she says. “You cannot parachute in with a solution – you need to understand the craft, the community, and the constraints first.” By engaging local entrepreneurs, universities, the government and residents, the team continued exploring both technical options and a new business model.

As the concept took shape, The Water Agency brought together a wider coalition to co-design the pilot. The Water Agency leads strategy and community engagement; Resilience BV oversees on-site engineering; Saxion University and Rietland contribute filtration and wetland expertise; and Universitas Pekalongan (UNIKAL) anchors the project locally as the future Green Batik Centre.

Building trust through collaboration

“When we first began discussing wastewater treatment with local producers, it wasn’t a welcome conversation,” Carrina recalls. “People know wastewater is an issue, but they don’t know where to start – and they fear the cost and the risk of changing.” Rather than pushing a problem narrative, the consortium reframed the challenge as an opportunity.

“We asked: what if the first ‘Green Batik’ comes from Pekalongan? Would you like to work with us on that?” Carrina explains. “That made people excited. It became a shared discussion, a shared journey. From that point on, we could begin talking about water as one of the obstacles standing in the way.”

“Currently we are working with four batik entrepreneurs,” Guido adds. “Eventually the pilot aims to work with ten.” These first four workshops – now known as Batik Champions – co-design, host testing and demonstrate the new systems. “They are deeply involved and genuinely collaborative,” he says. Carrina agrees: “This shift from compliance to ownership is essential. Our problems are also their problems. Our successes are also theirs. It’s the foundation of trust.”

Shells and air bubbles

At its core, the solution is deliberately simple. “We created a ‘wetland-in-a-tank’ concept using technical knowledge from our consortium partner Rietland,” Guido explains. “It functions like an artificial wetland, where bacteria living on the filter material break down the wax used in the dying process, dye residues and even faeces.”

Most components are locally sourced, reused waste products. “We fill second-hand tanks with waste seashells from restaurants,” Guido says. “They have a huge surface area for bacteria to live on.” With aeration from small pumps, the process becomes remarkably effective. According to Guido, the water is now around 90% cleaner than before treatment. “It goes from pitch black to almost transparent – cleaner than tea,” he says. “We’re still working on the final ten percent.”

“Ultimately, the goal is to make the system circular,” Carrina adds. “This way, the treated water could be reused in parts of the batik process, reducing groundwater use and closing the loop within each workshop”.

The team refines the system through trial and error. “Early on, insufficient oxygen supply caused the bacteria to die and clog the system,” Guido says. In another case, a workshop’s self-built masonry tank collapsed under its own weight. “The shells filled half the workspace,” Carrina recalls. Yet these setbacks strengthened cooperation. “Everything we do, we’re figuring out together with the entrepreneurs,” she says.

New opportunities

The project also invests in the next generation. Through a collaboration with the Dutch football association’s KNVB WorldCoaches programme, young people learn leadership and environmental awareness by linking sport to sustainable batik. “They learn responsibility – for themselves, for others and for their environment,” Carrina says.
The Dutch Embassy in Jakarta has further expanded opportunities through a Green Batik Design Challenge. “It shows that going green doesn’t only require extra effort,” Carrina explains. “It opens doors: new networks, new markets, new visibility. This is inspiring for local entrepreneurs.”

Looking ahead

The coming year will focus on technical refinement, cost optimisation and replication. The economic model is equally critical. “We are disrupting business-as-usual,” Carrina says. “Once we have a business model, we can begin talking to interested parties to scale up the solution.”

If successful, Pekalongan’s model could inspire sustainable batik production across Indonesia. For Guido, the clearest sign of success is market adoption: “If one workshop outside the project decides to buy the system, that’s when we know we’ve really achieved something.”