This cartoon may show the lighter side of life in Singapore but keeping Singapore's water resources clean is serious business.

As a small island that doesn't have natural aquifers and lakes and with little land to collect rainwater, Singapore needs to maximise whatever water it can harvest.

A pervasive network of drains, canals and rivers channels rain water to 14 reservoirs. Come 2009, this will grow to 17, with the completion of the Marina, Punggol and Serangoon reservoirs.

However, after a heavy rain, the waterways often turn brownish in colour, when silt gets washed down from exposed earth sufaces and construction sites. To tackle the problem of silty discharge, PUB has been working with the construction industry on concerted efforts in public education and engagement, technology upgrading, and enforcing good earth control measures.

To promote awareness, PUB jointly held a seminar with the Construction Industry Joint Committee (CIJC), a grouping of eight associations in the construction industry, on erosion and sediment control last year.

To raise professionalism in soil erosion practices, PUB amended its Code of Practice on Surface Water Drainage last year to provide more guidelines on how developers and contractors can effectively apply appropriate earth control measures at worksites. Now, developers and contractors submit to PUB appropriate earth control measures designed and endorsed by Qualified Erosion Control Professionals before the start of any construction work.

PUB and the Singapore Contractors Association Limited also jointly came out with a new guide book on erosion and sedimentation to highlight basic erosion control measures that contractors can adopt at construction sites to prevent silt discharges into waterways.

"Keeping our waterways clean and pollution-free is crucial as many of our waterways flow into our reservoirs which supply our drinking water. All these catchment areas and their watercourses, which are practically at our doorsteps, need to be protected for our own good," said Dr Amy Khor, Senior Parliamentary Secretary, Ministry of the Environment and Water Resources, at the CIJC-PUB Seminar.

Today, 217 construction sites use treatment technologies to control silty discharges from construction sites, compared to none two years ago.

PUB has also stepped up enforcement at construction sites. There were 227 offences

compared to 128 offences in 2005. If necessary, PUB will consider heavier penalties especially for repeat offenders.

In a combined effort to keep our waters pristine, product and technology suppliers have banded with the local construction industry and formed the Singapore Erosion Control Association. This association aims to be an effective technical forum for earth control measures with a view to form a local chapter with the International Erosion Control Association - the world's oldest and largest organisation devoted to solving problems caused by erosion and its fallout.

NEW LEASE OF LIFE FOR OLD SEWERS

Besides silty discharge from construction sites, PUB is also working on keeping the underground sewer system in tip-top condition and free of leakages that could contaminate our rainwater collection system.

Singapore is one of the few countries in the world which has separate networks handling rain water and used water. While rain water is transported through the drainage network, used water is managed by an underground sewer system.

Stretching over 3,400km, Singapore's sewerage network carries used water from residential and commercial buildings to water reclamation plants. Under PUB's 10-year programme to renew old sewers, some 790km of public sewers were rehabilitated.

As private sewers located within premises of private properties form an integral part of the used water collection network, a similar programme was also rolled out to help owners of private properties make good their aging sewers through innovative trenchless technologies.

Launched in August 2006, the programme covers about 600km of public and private sewers. Focusing initially on parts of Singapore where the sewer systems are older, PUB arranges free checks for property owners to assess the sewers at their premises and provides advice on rectification work if leaks are detected.

Should repairs be needed, PUB helps building owners by advising them on the rectification work required, providing them with a list of recommended contractors as well as subsidising part of the repair costs of these sewers.

Owners are free to choose any contractor to do the rectification works but those who need financial assistance in the form of monthly instalments can also engage PUB to do the repair works.

By TEO YIN YIN