in Cambodia

Identifying major pollution sources in Tonle Sap Lake

Background and objective

Tonle Sap Lake (TSL) is the beating heart of Cambodia with its reach and diverse ecosystems. It supports livelihoods of more than one million people as a major source of water and protein for Cambodian people. However, anthropogenic pressure together with climate change impacts lead to degradation of water environment of TSL. Man made threats including increasing discharge of untreated domestic and industrial wastewater, pollution loads from chemical intensive agricultural practices, etc. play vital roles in degradation of water environment of TSL. In response to this, the Government of Cambodia is developing the National Strategy for Water Quality Management in TSL. The WEPA Action Program is designed to outline the comprehensive water quality management plan (CWQMP) of TSL, which will setup up targets, and design action and implementation plans for improvement of water environment in TSL under the umbrella of the National Strategy. The activities of WEPA Action Program consist of developing methodologies on estimating pollution loads from major sources, developing a guidebook for local environmental staffs, and facilitating formulation of draft strategies of water quality management of TSL through a co-design and co-production approach, and capacity building training programs.


The WEPA Action Program in Cambodia is implementing following specific activities:

Development of methodologies to identify major sources and loads of pollutants
A detail case study is conducted to develop the methodologies to identify pollution sources and loads. The case study is conducted in Chhnok Tru village, located in Kampong Chhnang Province (Figure 1) and surrounding area. Intensive field survey is conducted to collect the information and data of pollution sources and the pollutants based on the on-site inspection

Development of a guidebook for sub-national environmental officers
The methodologies are elaborated in a guidebook for sub-national level environment officers. In order to develop the guidebook, the draft methodologies are consulted in a stakeholder consultation meeting to receive feedbacks of key stakeholders. Also, necessary counter measures for management of water environment in TSL are discussed. The outcomes of stakeholder meeting are documented in the guidebook.

Capacity building training for national and sub-national level environment officers
Capacity building training on the guidebook is organized for both sub-national and national officers. The training consists of both technical methodologies of pollution source and loads measurement and guidelines on the policy measures.

Outline of the activities and expected outputs of the WEPA action program are shown in Figure 2.

Figure 1. Location of study site

Figure 2. Outline of the activities and expected outputs


  • Guidebook for sub-national environmental officers on methodologies of identifying major pollution sources and potential policy actions in TSL
  • Capacity building workshop of local and national officers
  • Draft outline of the comprehensive water quality management plan of TSL