Stormwater ponds for sustainable and water resilient cities

There are 850 stormwater ponds of different shapes and sizes in Cape Town – use the map to zoom in and explore them across the city.

These seemingly unremarkable pieces of infrastructure look like empty, dusty, grassy or wet depressions but they are an important part of the city’s stormwater drainage system, which protects people, property and the environment from the impacts of stormwater.

During rainfall, stormwater enters a pond through an engineered inlet and is then slowly released through an outlet into the environment or receiving waterways.

However, stormwater ponds can do so much more than manage stormwater; there is potential to repurpose them to provide multiple benefits such as recreation space, biodiversity and aquifer recharge.

This study developed a science driven decision support tool to identify and evaluate the potential benefits that stormwater ponds could provide. The tool identifies strategic ‘priority’ stormwater ponds where there is high potential for multiple benefits to be provided towards sustainable and water resilient cities.

The benefit scores for each map were combined and weighted with the local expert stakeholder weights to produce a combined map showing the potential for multi-functional benefits.

On the map, the darker blue stormwater pond centroids show a higher potential to provide a combination of the seven benefits, and are higher priority to repurpose to create a sustainable and water resilient city.

Use the map to zoom in and explore the stormwater ponds' multi-functional benefit potential - click on the ponds to see their individual score from 0 (low benefit potential) and 1 (high benefit potential).