Enough has been said about the depletion of our supply of fresh water from industrialization, deforestation and climate change. Now, the rise of megacities is also complicating the problem.

In a recent report, the United Nations Family Planning Agency (UNFPA) predicted half the world's population would be living in cities by next year, with the figure expected to grow.

This presents challenges for more effective land use, transportation and the fulfillment of minimum daily subsistence. Cities that fail to meet these challenges will become "failed cities", marked by the rise of megaslums.

The problem with water is that it is complicated by the fact that policy in this area is highly intertwined with other sectors. More food requires fine agriculture, which can also mean more water. More clothing requires industrialization, which can involve the use of more groundwater and the pollution of water sources. Housing can also cause problems if built above water catchment areas.

Failure by states to provide their populations with adequate water for drinking and sanitation can be considered a violation of international law.

Under Indonesia's current system, access to "water sources" is guaranteed by the Water Resources Law. Articles five and 16 of the law stipulate that every municipality must fulfill the minimum daily basic water needs of its local community.

However, the Constitution is silent on the right to water. The Water Resources Law for example -- due to the absence of the right to water in the Constitution -- only cites Article 33 of the Constitution, part of the economic chapter regulating natural resources.

This could be a problem, since water rights could then be perceived as existing only as derived from the economic provisions of the Constitution. Contrary to this interpretation, the international community now regards the right to water to be a part of the language of human rights.

The Constitutional Court acknowledged that access to water is a human right in its decision on the judicial review of the Water Resources Law. However, the court's decision does not bear the same weight as a provision of the Constitution.

Explicitly incorporating the right to water in the Constitution does not appear to be helpful at first glance. Adding more words to the Constitution will not provide more fresh water. But that's not how the legal system works.

The law, operating in the language of rights and obligations, helps answer questions on how to prioritize the allocation and use of existing resources. If, for example, there is a conflict between the right of an individual and the right of a company to exploit water, who should prevail? Does an individual have the right to challenge a factory because the water in his or her well is being depleted?

With the rise of megacities, the problem most likely to emerge will be disconnections from the water network. Imagine that in the future -- all at the same time -- the quality of groundwater worsens, reserves drop thanks to interference with catchment areas and urbanization drives up demand for water.

More and more people will rely on water networks for their supplies. Will water companies be able to disconnect those unable to pay?

Here is the question of whether we should see water consumers as mere actors in the market economy (who get their water as long as they pay) or as citizens (who are entitled to water regardless of whether they can come up with the money). If such a cases were brought to local courts where judges were not aware that access to water was a human right under international law, there is the danger that judgments will end up reflecting the narrow, market-oriented view of the consumer.

If, once again, the water resources law is perceived as only a derivative of economic chapters of the Constitution (Article 33), then the outcome of cases such as the hypothetical above would likely follow what has happened with other natural resources such as oil, gas and minerals.

But the way people need water is not the same as the way they need oil, gas or coal. So it is not adequate to argue about the right to water within the realm of Article 33. The right to water must stem from the human rights provisions of the Constitution, and that can only occur if it is expressly stated.

This does not mean that processed water should be available to everyone for free. A price should be associated with it to encourage people to conserve available resources. However, the provision of water and sewerage should be from the perspective of being a public service.

Individuals receiving the service are not mere consumers purchasing goods in the marketplace. They should be treated as citizens receiving services from the state. Their entitlement to water should be guaranteed by the government even if they are unable to pay.

It is the state's duty to respect, protect and fulfill the right to water. The quality and quantity of the amount of water individuals are entitled to must be clearly stipulated in law and not left to market mechanisms to decide. Water companies will have to be efficient and sustainable but at the same time pay due regard to prevailing regulations. Therefore, regulations on subsidies to the poor as well as speedy and cheap dispute resolution mechanisms when it comes to water disconnections must be in place.

Putting the right to water in the Constitution will not directly solve our water problems, but it will clarify to the government that they have a constitutional responsibility to provide this most essential of resources.