A Smart Mix of Mutually Supportive Measures to Ensure a High Level of Water Service in Singapore Despite Scarce Water Resources
Singapore, an island state with little surface area, has limited domestic supplies of water and relies on water imports from Malaysia. To reduce its external reliance, as part of its long-term water strategy, Singapore developed and successfully implemented a mix of supply-side and demand-side measures utilising advanced technology, economic incentives and communication — all backed with the support of a well-run public utility company. As a result, Singapore is becoming more and more independent in procuring its water supplies, and drinking water services are technically and financially sustainable.
Singapore is a city-state in Southeast Asia with a land area of 719 km2 and a population of 5.6 million, making it one of the most densely populated countries in the world. Following colonial times and its role as a British trading post, Singapore was briefly a part of Malaysia before being expelled from the latter in 1965. Within a single generation, Singapore advanced from being a “Third World” country to a developed country, as the country’s progressive economic policy and its location as a commercial and transport hub delivered positive economic impacts. In 2015, Singapore was the third-richest country in the world in terms of GDP per capita.
Due to Singapore’s lack of surface area it is difficult to store an otherwise abundant supply of rainfall (2,400 mm per year), and this accounts for the country’s water scarcity.
The main source of natural fresh water is water imported from Malaysia. Under a long-term agreement that will expire in 2061, Singapore can transfer water from Malaysia for a price of less than 1 cent per cubic metre. The water is imported through three large pipelines across the 2km causeway that separates the two countries. While Singapore may be able to extend the agreement for continued water imports beyond 2061, it aims — quite understandably — to achieve self-sufficiency of its water supplies as soon as possible so that it will not depend on a foreign country for an indispensable resource. Even if domestic sources of supply are much more expensive than the price of imported water, autonomy of water supply is extremely important and has a correspondingly high economic value. This is the context in which Singapore has implemented one of the world’s most sophisticated water management systems.
Conflicts arising from the baseline situation
The baseline situation is that of a water-scarce future (beyond 2061) and an immediate risk because of the dependence on one major source of supply (from Malaysia). If worse comes to worst, the consequences would be dire to the whole society and economy of Singapore. “The extreme risk of disaster required an equivalent response”: this was the basis of developing and implementing a robust water management strategy, a major component of which is demand management.
Description of the applied measure, its introduction and operation
Through a period covering decades, Singapore has implemented a mix of supply-side and demand-side measures. Each measure powerful enough in itself to make a considerable contribution towards reaching a balance between water supply and water demand. As a smartly composed package of measures, together they form one of the most sophisticated and high-tech water management systems in the world—a system in which scarce water supplies constrain neither economic progress nor the well-being of the population. Below, we consider each of the main measures individually.
Initially, the single most important source of supply was the water purchased and transferred from Malaysia. By now, a blend of several diversified sources serves the city, reducing Singapore’s dependence on a foreign sources. Diversification implies that if any one major source becomes temporarily unavailable, the rest can still ensure at least basic supplies.
At present, 30 percent of water is supplied through the NEWater technology, turning wastewater into clean drinking water. In fact, NEWater is so clean that specific minerals needed to be added to provide it as drinking water. NEWater is increasingly accepted as a source of drinking water, especially among the younger generation. Its main use, however, is industrial, since its purity is higher than that of tap water; thus it is ideal for specific types of industrial manufacturing processes, like semiconductor production, which requires extremely clean water. Notably, the cost of producing NEWater is less than the cost of desalination. By 2060, NEWater is expected to cover 55 percent of the water need of Singapore (with water consumption expected to double compared to current levels). Since sewer penetration is complete and all wastewater is collected and treated, the application of the NEWater technology ensures that a given cubic metre of water is utilised several times before being lost through infiltration into the soil, “export” (supplying ships) or technological use.
25 percent of current consumption is met through desalination, a ratio that is expected to grow to 30 percent by 2060. Thus, in a little more than four decades, 85 percent of total demand is planned to be met through two main technologies: NEWater and desalination.
While the land area in Singapore is limited, rainwater is still a significant source of supply, partly because of high levels of precipitation. Water is being collected in reservoirs for subsequent drinking water production. Since 2011, the water catchment area has been increased from half to two-thirds of Singapore’s land surface with the completion of the Marina, Punggol and Serangoon reservoirs. In the long run, this ratio is planned to be further increased to 90 percent of Singapore’s land area. Most of the land area comprises unprotected catchments where development is allowed — for example, for residential, commercial and non-polluting industrial activities. There are also some protected catchments in the city where there are severe restrictions on land use, but these make up less than 5 percent of the total area.
The most important tool on the demand side is cost-recovering tariffs. As PUB claims, “the pricing of water is set to reflect the scarcity value of water, as well as cost of producing clean water from the next available source.” This encourages all water users to be more water efficient. The water bill consists of four components: a water tariff, a water conservation tax, a waterborne fee, and a sanitary appliance fee. The water tariff covers the costs incurred in various stages of water production, such as the collection of rainwater, treatment of raw water, and the distribution of treated water to customers through an extensive network. This tariff is based on the amount of water consumed. The water conservation tax is a 30 percent surcharge on the water tariff with the explicit goal of encouraging water savings, making customers feel that water is extremely precious in Singapore. The waterborne fee corresponds to the costs of treating used water (NEWater technology), while the sanitary appliance fee covers sewer-related expenses and is charged after each sanitary fitting.
The water tariff is progressive. The first 40 m3 of individual household consumption is subject to a lower tariff and lower water conservation tax than subsequent consumption. The shipping industry must pay a higher tariff because the water it purchases is taken out of domestic circulation (i.e. taken away by departing ships). The tariff schedule for different consumers can be found in the tables for potable water and used water (See table)
PUB also provides information to its customers to help them save water. This is partly comprehensive technical information for various water users, including tips on how to save water (https://www.pub.gov.sg/savewater), and partly “benchmarking” information displayed on the water bills (including the average consumption of neighbours living in similar housing types or streets), as well as the national average, so that customers can assess how they fare compared to others. This provides an incentive to try and save more water.
Another important water demand management measure is the constant high-tech monitoring and maintenance of the drinking water network, which results in water loss capped at 5 percent—one of the best such figures in the world. Singapore has a complex and sophisticated strategy to manage unaccounted-for water, as detailed in a guidebook: https://www.pub.gov.sg/Documents/UFW_Guidebook.pdf. Moreover, illegal connections in Singapore are non-existent, partly because of monitoring efforts, but also partly because of high mean income. Households with lower income receive targeted help to pay for part of the utility bills. Importantly, they are subject to the same prices as all other customers; in this way, the incentive effect of prices stays the same, but their burdens are eased through a rebate system.
Physical and ecological impacts of the measure
There are no major adverse impacts.
Financial and other impacts of the measure on different stakeholders
The cost-recovering, progressive water tariffs are eased for low-income customers through a rebate system available for all public utility services.
Resilience of achievements, sustainability of results
Results are sustainable because they are the outcome of a decades-long strategy that is very carefully planned and implemented, and also because of the high-level autonomy of the public utility (a prerequisite for cost-recovering prices). Moreover, there is a diverse mix of supply-side and demand-side measures, and this diversity also contributes to sustainability. Finally, Singapore is a high-income country with resources available for those investments that have a longer-term payoff.
- Ensured sustainability of water services.
- Cost recovery.
- Extremely low levels of water that is unaccounted for.
- Widespread public awareness of water-saving opportunities.
The case of Singapore is a uniquely successful story in water management, and as such, it is based on a unique set of success factors, each of which is important in its own way. There is a long-term strategic vision behind the measures, and this vision enjoys the full support of the government. Implementation of the water management strategy is reinforced through a relentless pursuit of efficiency: measures and policies are constantly monitored and improved. A dedicated and well-functioning government has played a crucial role in carrying out this successful water strategy. Widespread acceptance of the use of economic instruments and economic incentives, including full-cost pricing of water services, has also been essential.
- Consumption per connection per day.
- Unaccounted-for water.
- Share of wastewater reuse.
Individual elements of the Singapore water strategy are repeatable to some degree in most countries. However, developing and executing a coherent and efficient strategy that includes an optimal mix of supply- and demand-side solutions, requires long-term vision and stable commitment from government.
- Due to the long-term nature and complexity of the whole suite of applied measures, it is difficult to quantify the costs. However, because tariffs ensure cost recovery, the costs of the strategy do not need to be financed by external sources, as everything is paid for through the tariffs.
- Tortajada, Cecilia. Water Management in Singapore. Water Resources Development, Vol. 22, No. 2, 227–240, June 2006.