The increase in water prices announced by the Government on Monday may be necessary to control usage, but some experts said the jump needs to be bigger if it is to curb wastage.
Industry leaders and water experts said financial incentives can also be introduced to encourage both domestic and industrial water users to adopt water-saving measures.
The experts said the price increase only reflects the reality of increasing water stress worldwide.
Professor Ng Yew Kwang of Nanyang Technological University's Division of Economics, said the 30 per cent increase in the price of water is not excessive, as general inflation here has gone up more than 30 per cent since the last increase in 2000.
He said that there should have been a larger, one-step increase "to give a larger awakening effect for saving water", instead of the phased hikes to be rolled out this July and the next.
Industries now account for more than half - 55 per cent - of Singapore's total water demand, and this is projected to increase to 70 per cent by 2060. Overall water demand is expected to double by then.
Professor Asit Biswas of the National University of Singapore's Lee Kuan Yew School of Public Policy had pushed for a doubling of water price for industrial users, saying that such an increase should not deter industry.
The price of potable water for non-domestic users is $2.15 per cubic m, including water taxes and before goods and services tax, and will increase to $2.74 by 2018.
"Industry has the technology to reduce the amount of water they use. If they make changes in their management (of industrial processes and procedures), they can reduce their water use by 30 per cent to 40 per cent without difficulty," said Prof Biswas.
He said that multinationals like Nestle and Unilever realised the importance of saving water and reduced their use of water globally by 40 per cent over the past 10 years through internal incentive schemes.
Another example is Taiwan Semiconductor Manufacturing in Hsinchu city, Taiwan, which collects rainwater for reuse, purifies waste water for semiconductor processing and uses recycled water for toilets. In 2009, it saved 30 million tonnes of water, according to a report by The Guardian.
"A major campaign should be started (in Singapore) to make industry realise water is a strategic resource, and they have to reduce its use dramatically," said Prof Biswas.
By incorporating a different process which uses less water, Micron Semiconductor Asia ultimately generated more revenue.
The wafer fabrication company uses advanced equipment that sprays silicon wafers to clean them, using less water than the older method of immersing them in water. Although the process is 10 times more expensive, it causes less damage to the wafers, which led to higher revenue.
Mr Jagadish C.V., chief executive of Systems on Silicon Manufacturing, said rebates should be given to companies based on how much water they recycle.
Incentives should also be given to domestic water users, said experts. For example, in Zaragosa city in Spain, the water tariff is reduced by 10 per cent if annual consumption has dropped at least 10 per cent compared with the last two years.
In 2015, the World Resources Institute ranked Singapore highest in water risk alongside six other countries, most of which are in the Middle East.
Mr Sandeep Chamling Rai, senior adviser to the Global Adaptation Programme at the World Wildlife Fund, said the risk is already being seen in the low and uncertain water levels at Linggiu Reservoir in Johor, which supplies Singapore with a major part of its water demand in an agreement that expires in 2061.
The water level at Linggiu Reservoir stands at 32 per cent.
"Singapore's water price hike merely reflects the realities of increasingly stressed water resources in a warmer world," he added.
•Additional reporting by Audrey Tan
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