High-density polyethylene (HDPE) geomembranes have emerged as a critical technology for safeguarding ecosystems and optimising water storage, particularly in water-stressed regions like South Africa.
With the country’s per-capita water availability well below the threshold for physical water scarcity, estimated at under 1 000 m³/year, innovative solutions are essential to meet growing demand. South Africa’s network of over 300 government-owned dams, with a combined capacity of some 29,2 billion m³, underscores the scale of its water infrastructure yet also highlights significant losses due to seepage and evaporation.
By deploying HDPE geomembrane liners, water managers can both protect the environment from contamination and enhance water retention in reservoirs and tailings storage facilities.
Environmental protection
HDPE geomembranes serve as robust barriers in waste containment and environmental remediation projects, preventing leaks of hazardous chemicals into soil and groundwater.
Their exceptional chemical and ultraviolet resistance ensure long-term integrity even under harsh exposure, outperforming many alternative materials in durability tests. The low permeability coefficient of HDPE (around 1 × 10⁻⁹ cm/s) effectively isolates pollutants, making these liners indispensable in landfill and mining applications where containment failure could have catastrophic ecological consequences. Moreover, HDPE’s high tensile strength and puncture resistance reduce the risk of liner breaches during installation and operation, further safeguarding sensitive environments.
Water storage in water-scarce South Africa
In water-scarce South Africa, where average annual rainfall is roughly half the global mean, minimising losses in storage reservoirs is vital. HDPE dam liners offer a flexible, impermeable membrane that seals reservoir beds and channels, drastically cutting seepage rates and preserving precious water supplies.
The near-impermeable nature of HDPE — coupled with carbon-black additives for UV stability — extends liner service life to several decades, ensuring sustained performance without frequent replacements.
By reducing seepage and evaporation, HDPE-lined dams can maintain higher water levels during dry seasons, directly supporting agricultural irrigation and municipal water provision. Enhanced storage efficiency also contributes to better drought resilience, allowing communities to draw on stored reserves during extended dry spells.
As South Africa’s demand for reliable water supply continues to grow, the strategic installation of HDPE geomembranes will be a cornerstone of sustainable water management.
Gundle Geo Synthetics are experts when it comes to choosing the correct dam liner. By contacting Gundle Geo Synthetics you can ensure you get the dam liner perfectly suited to your needs, that will last for many years more.
Contact Gundle Geo Synthetics on (+27) 011-813-2180 or send an e-mail to ggsales@gundleapi.co.za. You can also visit their website at www.gundlegeo.co.za.
Sources:
https://www.greenpeace.org/africa/en/blogs/51757/water-crisis-in-south-africa/
https://www.mdpi.com/2071-1050/12/20/8682
