With Rockflow, Maasgouw municipality is opting for more effective water buffering and infiltration system than gravel or lava cases and crate systems offer. The innovative system stores twice as much water as lava and/or gravel. On top of that infiltration is faster since the bottom surface area of the buffer is available for water to percolate through. “Stone wool has such a high density (pore size less than 40 µm) that sand grains cannot infiltrate the system”, explains Lowie Eijkelhardt, civil technology project leader at Maasgouw Municipality. “The high absorption capacity of Rockflow also ensures that less material is required to achieve the intended buffer volume. Compared with lava cases this is a factor of more than 2. With Rockflow, less than half the amount of soil needs to be excavated.”
Maasgouw Municipality is proactive in Limburg regarding the disposal of stormwater. Rainwater is no longer transported to a purification installation via the wastewater sewer but is infiltrated via infiltration elements in the ground. This has two benefits: wastewater treatment plants perform better if the waste water to be processed is less diluted by rainwater, and infiltration improves the water balance and counteracts depletion of groundwater. The municipality has been replacing old wastewater drains and is placing new infiltration systems since 2008, increasingly relying on Rockflow for these systems. Furthermore, Rockflow has a high load-bearing capacity, as a result of which coverage of only 35 centimetres in depth is sufficient, which is an additional benefit” states Rob Driessen, business developer at Lapinus. “Due to this, the system can be installed very close to the surface of the road, which means it is one of the few systems suitable for locations with a high groundwater level.” Rockflow is also an environmentally friendly system. “Stone wool is made from volcanic basalt rock; a natural substance that is fully recyclable.”
Maasbracht, the Netherlands
Project location