The lack of proper sanitation facilities in Asia and the Pacific has a profound impact not only on health but also on human dignity. According to the Asian Development Bank (ADB), about four percent of all maternal deaths are linked to poor hygiene and sanitary conditions. The issue can even result in violence toward women as was the case in the Indian state of Uttar Pradesh state, where two women were allegedly raped and eventually murdered while seeking a discreet place to defecate.

India is considered to have one of the world's worst sanitation records, prompting the recently elected PM Narendra Modi to make public health as well as the country's garbage and sanitation troubles one of his government's key priorities. Some 594 million people in India - nearly 50 percent of country's population - defecate in the open, according to UNICEF.

Jingmin Huang, Senior Urban Development Specialist at the ADB, says in a DW interview that to address the issue, governments in Asia and the Pacific need to invest an estimated 71 billions USD to make sure all their citizens have improved sanitation. But the analyst also warns that new toilets alone won't be enough.

DW: How widespread is the lack of proper sanitation systems in Asia?

Jingmin Huang: We estimate that there are about 1.7 billion people in Asia who have no direct access to an improved sanitation facility.

Of these, 540 million - or 13 percent of Asia's total population - use public or some kind of shared sanitation facilities, while another 397 million - or 10 percent of all Asians - use facilities that do not meet minimum standards of hygiene and are what we would call unimproved sanitation facilities. The remaining 758 million, making up 18 percent of Asia's population, still practice open defecation.

The countries which suffer most from a lack of proper sanitation are India and the People's Republic of China. India and Indonesia are the countries in Asia which have the highest number of people who still practice open defecation.

What is the cost of the lack of proper sanitation?

It's hard to estimate the cost of the lack of proper sanitation because impacts come through higher health costs, lost days in school or jobs, and tourism or investment that might otherwise be made. Costs also vary between countries.

Studies by the Water and Sanitation Program administered by the World Bank have put the annual cost in India, for example, at about 54 billion USD or 6.4 percent of gross domestic product (GDP), and 780 USD million per year in Vietnam, cutting 1.3 percent from the country's GDP.

India is considered to have the world's worst sanitation record. Why has New Delhi so far failed to effectively tackle the issue of sanitation?

The government of India recognizes the need for a radical change in their sanitation strategy. Although the central government is providing resources within its means, the task of total sanitation cannot be achieved without broader public support. Notable bottlenecks affecting the quality of outcomes include limited behavior-change-led investments in sanitation, and a narrow range of technology options.

In a new national initiative of top priority, the central government is emphasizing behavioral change, alongside technological advances, as the key to effective sanitation.

Would building new and cheaper toilets be enough to improve public health?

This can certainly help, but just building the toilets themselves is not enough. It is critical to have in place the systems to treat sludge and wastewater if the full health and environmental benefits of having toilets are to be achieved.

The challenge to achieving the Millennium Development Goals (MDG) target for improved sanitation as well as the MDG target for reducing mortality rate among children under the age of five years is the treatment of human waste, not just the provision of basic sanitation facilities.

Right now, the sanitation needs of 2.7 billion people worldwide are served by onsite sanitation facilities, 1 billion of these live in urban areas across Africa, Asia and Latin America.

These facilities drain untreated sludge and wastewater into waterways and groundwater. Without faecal sludge or septage management and sewage treatment, the so-called 'improved sanitation' facilities will remain a significant source of waterborne diseases and water pollution.

And of course, once all the facilities are in place, it's critical to work with communities to make sure they understand the health and environmental value of using toilets rather than open defecation which, after all, is what many communities have done for millennia and, often, consider to be more sanitary.

How can investments in sanitation be economically viable and affordable to people who live on less than one USD a day?

The returns on investments in sanitation - whoever makes them - are high. A World Health Organization study in 2004 showed that a dollar invested in sanitation would provide an economic return between 3 USD and 34 USD, depending on the intervention and region.

Many investments will and should be made by governments, development institutions and private companies. Communities also need to be part of it and experience shows that when families understand and experience better sanitation, they understand the value: everyone gets sick less often so children can go to school regularly and their parents to work.

Furthermore, they don't need to pay as much for medical care, for example. Privacy and human dignity are elements that are hard to put a price on. Paying for sanitation is both worthwhile and makes the system sustainable.

How much would the Indian government need to invest to provide proper sanitation to all those in need?

Asia and the Pacific would need around 71 billion USD in investments to make sure all its citizens have improved sanitation. This needs to be made a priority for governments if their citizens and economies are to grow and flourish.

In India, the government estimates around 40 billion USD in investments over 2012-2032 is required to achieve full coverage of sewerage. This figures increases by another 40 billion USD considering related investments in solid waste and storm water drainage.

What else must governments do to address the issue?

Much more needs to be done and many players have a role. New and innovative technologies are needed, new business models should be explored, and new financing options should be considered, including from private sector.

The key to all these, of course, is the change in mindset of decision makers. They need to understand that deferring action is no longer an option because delaying action will ultimately cost more.

What effective sanitation measures are being undertaken around Asia and the Pacific?

There are many different initiatives taking place in the region depending on the local issues. The common denominator across all these initiatives though is the effort to educate people and heighten public awareness on the urgency of addressing sanitation.

Bangladesh and Nepal, for example, have done extremely well to reduce open defecation by building toilets. Bangladesh notably has targeted slum areas. The People's Republic of China and Vietnam, by contrast, have had a lot of success in improving sanitation and cleaning rivers and cities by building large wastewater treatment plants.

Jingmin Huang is Senior Urban Development Specialist at the South Asia Department, of the Asian Development Bank.