In the Namib Desert, before dawn, a small tenebrionid beetle climbs onto a dune, encountering foggy wind, and tilts its body. Water droplets condense on its hard outer wings and flow towards its mouth. This survival strategy inspired South African designer Shakira Jassat to seek alternative solutions for buildings: is it possible for building surfaces to also collect water?
Her answer is the Aquatecture Water Harvesting system, which consists of modular panels installed on building facades to collect rainwater. These panels direct water through downspouts into storage tanks, turning vertical surfaces into collection zones.
The idea came to Jassat when she observed rain running down bricks opposite her house. She wondered how buildings could capture this water instead of diverting it away. Traditional rainwater harvesting methods usually rely on roofs and gutters, whereas Aquatecture utilizes facades, which Jassat believes is particularly relevant for high-rise buildings and other structures with large vertical surfaces.
Water enters the tank via the panels under gravity. Removable downspout sections allow for cleaning. The long-term goal of the project is to provide water for non-potable needs, such as toilet flushing and use in washing machines.
For Jassat, integrating the system into the architectural language is crucial, not just the water collection process itself. The concept developed parallel to Shakira's research into other methods of atmospheric moisture collection, including studying fog and humidity harvesting technologies, in collaboration with the Faculty of Engineering at Eindhoven University of Technology.
A semester student study analyzed the possibility of collecting water vapor on panels in South Africa. The study showed that it was possible, but the collection level was insufficient to support the entire concept. As a result, the project focused on the more practical possibility—collecting rainwater.
The project then moved to a pilot phase. Engineers Without Borders joined after one of the engineers working on the V&A project connected them with Jassat. In 2021, she selected ten students from the Engineers Without Borders South Africa Cape Town University student society, representing various disciplines including geomatics, humanities, mechanical engineering, civil and chemical engineering, to study and evaluate the Aquatecture pilot installation.
The pilot installation was placed in a parking garage in the V&A Waterfront area, opposite the Orange Street Farmers Market. Students regularly visited the site to monitor the water level in the tank and the amount of precipitation, collecting data to assess the system's capacity. The project reached an early milestone when the storage tank, sponsored by JoJo South Africa, filled with collected rainwater. Students connected a hose to the tank, and the water was used to water shrubs at the nearby Orange Street Farmers Market.
However, the pilot project also revealed difficulties in measuring the volume of collected water. Wind, in particular, complicated forecasts, forcing researchers to consider how changing conditions affect the relationship between precipitation amount and collection capacity. Researchers also studied the environmental impact of the system's materials. With limited and incomplete local data on embodied carbon, they collaborated with suppliers and transport companies to gather information on recycled materials and calculate the pilot's embodied carbon. The results obtained were intended to help determine adjustments to reduce emissions in the final product.
This work allowed testing the system in a real urban environment while simultaneously investigating issues of materials, environmental impact, maintenance, and performance. The pilot installation in the Waterfront in Cape Town remains in place, and the collected water is used for plant irrigation. Jassat notes that she appreciates that people can use the space without necessarily noticing the water supply infrastructure. The goal was to demonstrate that water supply infrastructure does not necessarily have to be visually separate from architecture.
Jassat reports that Aquatecture has generated significant interest. The system was presented at Dutch Design Week, as well as at many other exhibitions and attracted media attention, but she would like this attention to translate into practical application. She noted: 'I would like to have a greater impact than just attracting attention in this project.'
The difficulty, according to her, arises when interest needs to transition into investment, manufacturing, and construction.
Manufacturing became one of the central issues. Jassat aims for the system to be produced as locally as possible. Interest in the technology spread to Kenya through an architect working there, but Kenyan manufacturers were unable to produce the system. This prompted further study of local panel production in South Africa and other parts of the continent, while Shakira is also looking at manufacturers in India and China.
The production process itself must adhere to technological principles, which implies considering materials, durability, and the ability to maintain the system over time. Someleze Mbele, who worked with the student group alongside Shakira within the Engineers Without Borders project and participated in field research during the pilot phase, stated that the feasibility and accessibility of modular rainwater collection on a wall heavily depend on materials, manufacturing, and local supply.
Engineering requirements are also very important. Panels must withstand weather, UV radiation, corrosion, and physical damage. Collection and storage systems must remain accessible for cleaning, and structural connections must be designed with safety and durability in mind. Mbele emphasized: 'Materials must resist weather, UV, corrosion, and physical damage,' adding that collection and storage systems must be 'easy to clean and maintain and minimize blockages.'
He also noted that 'decentralized collection systems should not necessarily be seen as a replacement for large-scale municipal infrastructure. Rather, they can complement existing systems, increasing resilience and reducing the load on centralized water sources.'
Dr. Ferrial Adam, CEO of WaterCan, believes the broader issue lies in designing less water-intensive buildings alongside finding additional sources. She argues that alternative sources can be viewed as a sustainability factor without addressing the question of how much water the construction consumes.
'We really need to consider how to save water, how to build future buildings that use less water,' she says, insisting that water resilience must be integrated into development, not added afterward. This could include reusing water within buildings, such as directing water from handwashing into toilet tanks, alongside rainwater harvesting. Adam believes this approach should extend to poor communities where water tanks, cisterns, and community or temporary sanitation facilities often serve as a response to inadequate services.
She sees a similar need in industry, mining, and agriculture: when designing more sustainable systems, water consumption and pollution must be considered. For Aquatecture, wider adoption requires builders willing to invest, manufacturers capable of producing the panels and systems, and users who can maintain them. Funding remains a hurdle. Jassat primarily self-funded the development, except for support for pilot projects. A developer from Johannesburg expressed interest but questioned clients' willingness to invest.
The project is not yet ready for the market. Its pilot tests show that the system can be built and tested, but Jassat feels it is too early to speak of measurable impact at full scale. She continues to work on materials, manufacturing, funding, and partnerships. For her, success will be measured by whether the system provides: 'When it collects water and flushes toilets, that is success for me.'