International Environmental Technology Centre 


Demonstration of ecological and other decentralized sanitation in the Philippines


Ecologocal santiation in the PhilippinesWastewater management is receiving receiving more attention in recent years because of the global water crisis. The concern is not only with the quantity of available freshwater, but also with its quality. Increased water demand resulting from urbanization and food production needs cause the unregulated and illegal discharge of untreated wastewater into the environment, leading to the contamination of freshwater resources. In Asia, there is growing concern that inappropriate wastewater management could hamper sustainable socio-economic development. Eventhough remarkable progress in sanitation has been made in large cities for the past decades, it is not sufficient to cover the needs of an ever-increasing urban population. It is estimated that 84 to 89% of wastewater is untreated when discharged and polutes freshwater reservoirs as well as coastal waters. Negative economic impacts from this pollution cost several percentage points of national GDP to some Asian countries.

Needs to be addressed

The project  “Demonstration of ecological sanitation and other decentralized sanitation in the Philippines” is designed to address wastewater management issues by adopting small-scale Environmentaly Sound Technologies (ESTs) at the local community level on a pilot basis. Unlike Asian megacities, where sanitation coverage is relatively good, most peri-urban and rural areas lack appropriate wastewater management systems, as centralized treatment systems require dense population to be cost-effective and are not realistic solutions for these areas. Alternative solutions are needed: Decentralized Wastewater Treatment Systems (DEWATS) and Ecological Sanitation (Eco-san) are highlighted as promising options to balance socio-economic development and provision of basic services for less privileged communities.

Project implementation

DEWATS and Ecosan are comprehensive approaches to sanitation rather than just technical hardware packages.

DEWATS is based on a combination of treatment principles such as biogas digester, anaerobic baffled reactor, anaerobic filter and planted gravel filter. The selection of these components is determined based on their reliability, longevity and tolerance toward inflow fluctuation. Most importantly, these treatment principles eliminate the need for sophisticated control, maintenance and technical skills.

Ecological santiation exampleEcosan is based on the principle of systematic water and nutrients reuse and recycling, as a hygienically safe, closed-loop and holistic alternative to conventional sanitation solutions. Ecosan systems enable the recovery of nutrients from urine and feces for agriculture, thus preserving soil fertility, assuring food security, minimizing water pollution, use of synthetic fertilizers and sometimes recovering bio-energy.

IETC implemented the project in collaboration with the Center for Advanced Philippines Studies (CAPS). Three different activity components were implemented:

  1. Pilot demonstration of ecological sanitation / decentralized sanitation in Bauang Municipality, Philippines.

  2. Rural-urban partnership on the use of sanitation products for agricultural use.

  3. Compilation of cases of Ecosan and decentralized sanitation in selected Asian countries.

For further information, please navigate to each activity's web page.

The project owes its success to the active participation and involvement of stakeholders. Thanks to longstanding efforts by people in the Bauang municipality, the town is now recognized as a model for decentralized (DEWATS) and ecological sanitation (Ecosan) and receives many visitors, including from abroad. This recognition encourages users, farmers, local communities and government staff to further improve the performance of existing facilities and promote their achievements. This virtuous cycle boosts sustainability of activities. UNEP-IETC will analyse and systemise this best practice for further implementation of similar projects.

This project is funded by the Korean International Cooperation Agency as a component of the project “Water Management and Resource Efficiency for Green Growth in East Asia” under the East Asia Climate Partnership.