Cleaner water from new drainage

The Business Times 15 Sep 09;

JTC's eco-friendly drainage system reduces the amount of pollutants in the water, improving the quality in reservoirs downstream

SUSTAINABLE development has become a growing imperative and across the world, governments and corporations are investing more than ever in new technologies to reduce pollution and energy consumption.

Some agencies are leaving no stone unturned in their search for the next green application. In fact, they are making use of stones - gravel and sand to be exact - in drainage systems to produce cleaner water.

Gravel filtration system

Industrial landlord JTC Corporation will be testing out a gravel filtration system at one of its upcoming estates, the Business Aviation Complex in Seletar Aerospace Park. The project is the result of a study which started late last year, looking at how rainwater can be filtered through layers of gravel, rough sand and granite debris before it runs into the public drains.

Concrete drains in most industrial estates today channel unfiltered storm water directly into waterways and reservoirs. With the new gravel filtration system in place, large volumes of storm water can be cleansed before entering public drains. This helps reduce the amount of pollutants in the water, improving the quality in reservoirs downstream.

'This is our effort to support the overall sustainable development of Singapore, and do our part to make sure the water run-off from our industrial estates is made cleaner, and help reduce pollutants or load to the waterways and reservoir systems,' said JTC director of engineering planning Koh Chwee.

The new drainage system can also look better than traditional concrete drains. As the Seletar Aerospace Park is nestled in greenery and the old-world charm of Seletar, the drainage system will be designed to blend in with the environment. The gravel surfaces can be covered with soil and planted with trees, adding colour to the estate.

Furthermore, it can make good business sense to explore storm water pollution control measures - investors and industrialists have become increasingly conscious of environment and corporate social responsibility issues.

The Business Aviation Complex will sit on a 7,000-square-metre compound which channels rainwater through the gravel filtration system. JTC has appointed a consultant to design the system and expects to complete it in 2011. The agency is the overall planner for the Seletar Aerospace Park - an aviation hub for maintenance, repair and overhaul, design and training services.

JTC will monitor the new drainage system for its cost and effectiveness in improving water quality. If it proves to be successful, JTC may introduce it to other industrial estates in Singapore.

The concept behind gravel filtration systems is not new and countries such as Germany, Australia and New Zealand have such features in place. JTC studied various systems and the challenge for it was to design one that would suit Singapore's geography and apply it in an industrial area.

For instance, JTC had to come up with a gravel filtration system that would accommodate heavy rains in Singapore. During the research phase, the agency found that heavy rainfall could exceed the drainage system's load, and it had to make modifications to prevent overflows.

In public housing estates, the national water agency PUB has introduced another type of drainage system known as bio-retention swales. Drains along Sengkang West Way for instance, have troughs of shrubbery which filter rainwater through soil layers.

Storm water management

Besides Seletar Aerospace Park, JTC is also looking to introduce a storm water management system at the new CleanTech Park at Jalan Bahar, a centre for the development and production of clean technology products.

JTC has started drawing up the master plan for the area and considered implementing a wide range of eco-friendly practices. The CleanTech Park will have a 'central green core' which captures surface run-off, and then uses retention, detention and cleansing techniques to make the water suitable for non-potable use.

JTC displayed its environmentally-sustainable drainage systems at the Singapore International Water Week this year. Local and international visitors from both the academia and corporate world were supportive of its initiatives, it said.

The new drainage systems are part of JTC's initiatives in bringing innovative and sustainable real estate solutions to its industrial parks. The agency is no stranger to the sustainable development movement, being the key manager of supply and demand for scarce industrial land in Singapore. It has been spearheading Singapore's industrial growth since 1968.