Under this scenario what is scary is that water consumers in the Klang Valley will have to brace themselves for more rounds of water rationing until inter-state water transfer schemes are completed.

To get the best out of a bad situation, the Selangor Waterworks Department (JBA) should find ways to improve its management of water rationing. Since the last four months of water rationing in parts of the Klang Valley, not a day has passed without some news of consumers being left high and dry without water for days on end.

The response of the Waterworks Department is often the stereotype answer that the problem is due to low water pressure, that consumers' houses are located on high ground, or that they are at the end of distribution lines. The answer is as unsatisfactory as it is not surprising.

The department is simply helpless. It has openly admitted that it lacks many things like manpower and tankers to manage the situation well. But what it probably lacks most are the necessary information of its pipe network and the tools of modern technology to operate a water distribution system efficiently.

Accurate and up-to-date knowledge of the configuration of the whole distribution system, as well as the location, condition and performance of underground assets are basic prerequisites to the running of any city water supply distribution network.

A study carried out in 1986 covering Petaling Jaya unearthed quite a large number of plans and maps of the pipelines available in the Waterworks Department. Most were "as-built" drawings prepared by those responsible for laying them. Others were drawings of alterations and additions to existing networks.

But there was a lack of co-ordination and uniformity in presentation and an absence of a system for updating and referencing. The study also found that the water supply distribution network in Petaling Jaya was part of the ever-expanding Klang Valley supply system which had become so complex that it was not possible to isolate Petaling Jaya as a separate and discrete entity.

When problems of poor pressures arose, valves were throttled, reservoirs bypassed, and pressure zones inter-connected in ad-hoc, trial and error attempts at solutions. That was more than a decade ago. It would seem that the present situation is no better if the poor showing of the present water rationing is anything to go by.

After four months of trial and error, there are still some consumers receiving no water for days at a stretch even on days when they were supposed to have water under the water rationing programme.

But much more is required than mere updating of records to administer efficiently water rationing in a complex supply and distribution system like the one in the Klang Valley.

The size and complexity of the systems involved and the interaction between various system components are such that it is no longer possible to run the system effectively and efficiently without the use of modern computing and electronic technology.

The computing and electronic technology available to water supply rnanagement and operation has increased dramatically over the last two decades. The most important benefit to be derived from these technological advances is network modelling and analysis. Network modelling and analyses require the creation of a geographical information system (GIS), which is a computer-based system for recording, displaying, and manipulating data associated with geographically located facilities.

It is fundamental to the management of the water industry and the control of its assets, be it for operational or planning purposes. From this GIS, a computer network model or models of the water supply distribution system can be generated.

This is a computer-based tool which, when property calibrated, is capable of providing a satisfactory simulation of the actual behaviour of the system, either at a particular moment or over long periods, say, 24 hours.

It can be used to carry out network analyses and simulations to identify shortcomings and other supply problems within the distribution system. From the results of the analyses, appropriate improvements to the system can then be made.

For water rationing purposes, this network model is a prerequisite to planning areas to be effectively isolated from the main system and ensuring that no single area is left high and dry irrespective of whether it is on high ground or at the end of the distribution lines.

The current approach - waiting for consumers to complain and then making some adjustments to suit - is clumsy, out-of-date and not in step with the nation's status of development.

The current water crisis is a lesson to be learnt. A balanced emphasis on the production of potable water and the maintenance and improvement of the supply and distribution sytems should be adopted. The long neglect of the distribution system is certainly the single major contributory factor that has turned a manageable water shortage problem into a crisis that is just short of becoming a catastrophe in the Klang Valley.