Part of a network of water treatment plants, the Seletar Water Reclamation Plant is a key component in Singapore's plan to become self-sufficient in the production of fresh water. The Seletar plant processes nearly 250,000 cubic meters (327,000 cubic yards) per day of wastewater from the city's sewers. This high-quality water can be mixed into Singapore's reservoirs where, after conventional water treatment, it is suitable for use as drinking water.
Recently, the Seletar Water Reclamation Plant added a new post-tension concrete containment tank to hold recycled water. The post-tension method incorporates steel strands that run throughout the concrete slab. While this construction method reduces cracking and enables concrete slabs to bear more weight, it requires additional waterproofing to prevent corrosion and deterioration of steel cables.
Since the recycled water stored in the new tank could potentially enter the country's water supply, all construction materials needed to be non-toxic. Furthermore, a tight construction timeline provided just 30 hours for the tank to be poured and to set.
Recognizing that conventional waterproofing membranes deteriorate over time, the Seletar project architect specified a crystalline waterproofing admixture for the project. The project team used Kryton's Krystol Internal Membrane (KIM) because of its superior waterproofing and corrosion protection properties. Certified safe for contact with potable water by NSF International, KIM provides an ideal waterproofing alternative for water supply projects.
When added to a concrete mix, KIM cures to form crystals that fill the spaces between concrete particles, providing permanent protection against leakage from any direction. KIM also reacts with incoming water to self-seal small concrete cracks and eliminates the corrosion of reinforcing steel by blocking the penetration of water that may carry harmful chemicals. Four hundred cubic meters of KIM concrete was used in the Seletar water tank. By eliminating the time and costs associated with installing conventional membranes, KIM enabled the builders to meet their tight construction timeframe.