Phnom Penh, the capital city of Cambodia, is now under the restoration after the civil war in the 1970s. The city is located west of the confluence of the Mekong and Tonle Sap Rivers. The city originally developed on the relatively high natural levees, and has been expanding to the west and south with the construction of a ring dike. Urban drainage facilities have been gradually installed in line with the development of the city. However, the system was not in function due to the deterioration by aging and the war-related damage, and the city suffered from frequent flooding and inundation, bringing about serious constraints to the social and economic development in Phnom Penh and the whole country as well.

In the comprehensive master plan for flood protection and drainage improvement, the southern part of the city was identified as the most vulnerable area to flooding, where the construction works started in 2002, and successfully completed in 2004.