Caption: The product is a breakthrough in paste technology to create a no-fines concrete that uses sufficient paste to coat and bind the aggregate particles together, forming a system of highly permeable, interconnected voids that drain freely and quickly.

With the dramatic escalation in urbanisation, efficient stormwater management is an increasing challenge to reduce the risk of flash flooding and sustain natural water cycles. Lafarge Readymix recently launched an innovative product to the South African market. Hydromedia is a new fast draining concrete pavement solution, which provides rapid stormwater removal from streets, parking surfaces, driveways and walkways.

The advanced drainage technology in Hydromedia has been developed by the international Lafarge group. While this unique product outperforms traditional permeable pavements, it also minimises the cost and long-term maintenance for local authorities and developers of stormwater management infrastructure.

“Hydromedia represents a significant technological advance in addressing important environmental issues associated with residential developments,” comments Neville Wearne, Lafarge national marketing manager for Readymix.

“This porous pavement concrete is instrumental in recharging groundwater while reducing stormwater runoff and can form part of a cost-effective Sustainable Urban Drainage System (SUDS). It also allows more efficient land use by eliminating the need for retention ponds, catchment basins and other stormwater management devices. In addition, the product acts as a filter mitigating contamination of groundwater by surface pollutants.”

“Water is a scarce resource in South Africa and requires very careful management, planning and protection; this includes our precious groundwater, which is often forgotten. In urban areas, permeable paving is an important type of SUDS. The Green Building Council of South Africa (GBCSA) has welcomed innovative design SUDS solutions that protect and conserve our environment,” says Manfred Braune, technical executive of GBCSA.

The key to the unique properties of Hydromedia is Lafarge’s breakthrough in paste technology to create a no-fines concrete that uses sufficient paste to coat and bind the aggregate particles together, forming a system of highly permeable, interconnected voids that drain freely and quickly. The mix is particularly fluid in application but highly robust and resilient after placing and curing. It results in a much simpler application, improving not only the workability of the concrete mix but also its consistency. The rheological properties that have been achieved strike a balance between fluidity and viscosity, producing short-term flexibility and long-term strength.

“We are proud to have adapted this world-class technology for the benefit of South Africa’s construction industry,” Wearne adds.

“We work closely with all players in the construction chain in order to channel our unparalleled technical strength at innovation into improving construction processes,” he maintains.

In the case of Hydromedia,this means that in addition to its superior permeability performance of 150 to 1 000 litres per minute per square metre, the product has high fluidity, making it easy to place as well as staying workable for up to 90 minutes. The final finish is durable, smoother and, together with being available in a range of integral colours, aesthetically more appealing than other permeable pavements.