In cooperation with

Maankwartier Heerlen

What makes this project unique is that there are beautiful trees in an (almost) impossible growing location, but we managed to create optimal growing conditions by mimicking nature. 

Heerlen, The Netherlands
Water capacity
3500 m²


Take a closer look at this project at Maankwartier:

Maanplein in Heerlen is the central plaza in the completely rebuilt city-centre, surrounded by high rise apartment buildings. It is one of 3 interconnected rooftop parks sited above the shopping center, Central train station and a parking garage.

It is intended as a place where people come together to walk or enjoy public events. Mature trees grow in specially designed mounds of lightweight soil on top of the roof over the shopping center. The entire square functions as a water collection basin with the use of the Permavoid 85 Capillary Irrigation System, and the water made available for the trees using the capillary irrigation system.

Beautiful trees in an (almost) impossible growing location


Watch the construction video of Maankwartier here:

Award winning nature-based solution: 5 Japanese Pagoda trees, 8-12 m high at time of planting


Trees capillary System

With the Permavoid Capillary Irrigation System an artificial groundwater level is created beneath the rootzone, mimicking groundwater in a natural situation, enabling the growing site to capture, store and reuse stormwater for irrigation. In this arrangement trees prevent stormwater entering the sewer whilst simultaneously enjoying a water reservoir to sustain growth during prolonged dry spells.

The Permavoid Capillary Irrigation System is equipped with specially developed fiber columns that provide capillary transport of water from the Permavoid retention buffer to the rootable soil above. This natural irrigation system uses no energy and maintains a consistent soil moisture content such that the tree experiences a very stable groundwater level, allowing it to thrive in the urban environment.

See how we do Trees

Inspiring projects

We have built a reputation

Find your local distributor nearby.

Permavoid source control ensures that no precious water goes to waste by catching, storing and reusing stormwater for irrigation, evaporation and infiltration. Find your local Permavoid distributor here to learn more about the technology and become part of the international movement.