VersiTank® infiltration and percolation tanks were installed to form a vegetated bioswale network integrated into the landscape grounds of the Firefly Park @ Clementi. The bioswale facilitates drainage in the park as an environmentally friendly alternative to open concrete drains. Sumps installed at strategic intervals along the linear swale, permit easy maintenance and inspection as water makes its way to discharge points positioned at where the gradient of the park is lowest before entering the external drainage network for discharge.

Slow percolation of rainwater from the surface into the tank below through a 100mm sand layer and the geotextile which envelopes the entire linear installation of VersiTank allows stormwater to be filtered at source. The slow percolation process together with the equally slow process of infiltration of water from the tank into the surrounding substrate coupled with the inherent water retention capability of the bioswale network itself also minimises downstream impact from high volumes of water in torrential downpours that often cause flooding.

The plants of the vegetated bioswale enable overall landscape design of the park to remain seamlessly green not possible when conventional concrete open drains are used for drainage within the park. At the same time phytoremediation by the plants of the vegetated swale also helps to remove organic contaminants and reduce suspended pollutants reaching reservoirs.