Cities in the Netherlands are experimenting with a greener approach to urban surfaces by using grass-filled permeable paving blocks in places where conventional sealed concrete or asphalt might otherwise be used. These specially designed blocks contain open spaces where grass can grow, while gaps in the surface allow rainwater to pass through rather than immediately flowing into drains. The approach can help reduce stormwater runoff during heavy rainfall and, depending on local soil conditions, allow water to infiltrate into the ground or be temporarily stored below the surface. At the same time, introducing vegetation in place of completely sealed surfaces can contribute to cooler, greener urban environments during hot weather.
Why Dutch cities are swapping solid concrete for grass-filled paving blocks
Conventional roads, car parks and paved public spaces are largely impermeable, meaning rainwater cannot easily soak into the soil beneath them. During intense rainfall, large volumes of water can quickly flow towards drains and sewer systems, increasing the risk of localised flooding when drainage capacity is exceeded.Grass-filled paving offers a different approach. Sometimes called grass pavers or open-cell concrete blocks, these surfaces contain gaps where vegetation can grow and rainwater can pass through. Depending on the design and local soil conditions, water can infiltrate into the ground, collect temporarily in underlying layers or be released more slowly into drainage systems.The Netherlands has long placed water management at the centre of urban planning, and climate change is adding new challenges. Heavier rainfall, periods of drought and increasingly hot weather are pushing cities to explore ways of making neighbourhoods better equipped to cope with extreme conditions. Replacing unnecessary sealed surfaces with permeable alternatives is one tool available to urban planners.
Grass-filled paving can help cities manage heavy rainfall
One of the main advantages of permeable paving is its ability to manage rainwater closer to where it falls. Traditional concrete and asphalt surfaces force water to flow across streets and pavements towards drainage systems. When exceptionally heavy rain falls in a short period, these systems can become overwhelmed.Permeable paving can slow this process by allowing some water to move through the surface. This can reduce the volume and speed of stormwater runoff entering drains at once. In suitable conditions, some of the water may also infiltrate into the soil below.However, grass-filled paving does not guarantee that all rainwater will immediately enter the groundwater. Its effectiveness depends on soil permeability, groundwater levels, construction methods and maintenance. Some systems are designed to temporarily store water beneath the surface before releasing it gradually.
Grass and vegetation can help reduce urban heat
The potential benefits extend beyond rainfall. Concrete and asphalt can absorb solar energy during hot weather and release stored heat later, contributing to the urban heat island effect that can make densely built areas warmer than their surroundings.Vegetation can contribute to local cooling through evapotranspiration, a process in which plants release water vapour into the atmosphere. Replacing completely sealed surfaces with greener alternatives can therefore play a small role in creating more comfortable urban environments.The cooling benefits should not be exaggerated. Grass-filled paving alone cannot dramatically lower temperatures across an entire city. Its contribution is more meaningful when combined with trees, parks, green roofs and other forms of urban vegetation that provide additional shade and cooling.
Part of a wider green and blue transformation
Grass-filled paving blocks are part of a broader approach often described as green-blue infrastructure. The concept involves integrating vegetation and water management into the design of streets, neighbourhoods and public spaces.Rather than treating rainwater solely as something that needs to be removed through underground pipes as quickly as possible, cities can create areas that absorb, slow or temporarily store water. Measures can include permeable surfaces, rain gardens, bioswales, green roofs, ponds and specially designed public spaces capable of holding excess rainwater.Dutch cities have explored different combinations of these measures according to local conditions. Together, they can help reduce pressure on drainage networks while adding greenery to densely built neighbourhoods.
Not every road can become a grass-covered street
Despite their environmental advantages, grass-filled paving blocks are not suitable for every location. Roads carrying heavy and continuous traffic generally require durable surfaces capable of handling significant loads and repeated wear. Grass may also struggle to survive where vehicles constantly pass over the same sections.For this reason, grass pavers are generally more practical in selected locations such as parking areas, residential spaces, driveways, verges and other relatively low-traffic surfaces.Maintenance is another important consideration. Openings in permeable paving can become clogged with sediment and debris, reducing the amount of water that can pass through. Vegetation also requires suitable growing conditions, while prolonged drought can affect grass and other plants.
A simple idea with a potentially wider role in climate-ready cities
Grass-filled paving is not exclusively Dutch, and permeable pavement systems are used in many countries. What makes the Netherlands particularly relevant is its broader emphasis on integrating water management and climate adaptation into everyday urban planning.As cities around the world face heavier rainfall, flooding and rising temperatures, reducing unnecessary sealed surfaces could become an increasingly important part of urban climate adaptation. Grass-filled paving blocks alone cannot solve flooding or heat stress, but they demonstrate how ordinary infrastructure can be designed to perform multiple functions.A surface can support vehicles or pedestrians while allowing water to pass through and creating space for vegetation. When combined with trees, parks, rain gardens, green roofs and effective drainage systems, such approaches can help make cities more resilient to extreme weather while creating greener and potentially cooler neighbourhoods.
