Vientiane is the capital city of Laos which is situated on the Mekong River near Thailand. The total population of the city is approximately 1,024,067(2013). Vientiane is bounded by Nam Nung River in the north and Mekong River in the south by latitudes 1754’ N to 18 18’N and longitudes 102 24’E to 103 00’E. It has a tropical wet and dry climate with distinct monsoon season and a dry season.
At national level 58% of the population has an access to water supply while 62% in Vientiane city. The city has surface water of 334,719 m3 and ground water is 3,958,117 m3 of which 65.57% is used for domestic purpose and 8.30% for industrial purpose (Water Resources Environment Administration).
According to Lao Institute for Renewable Energy the population of Vientiane is growing 5% a year and with the growth in population, organic pollution is becoming a serious problem in the city. A recent study by UNESCO/KEIZO OBUCHI reported that “As the economy and communication networks develop, the number of people in urban Vientiane city begins to grow more rapidly continue to improve urban condition. The lack of insufficient drainage system, Vientiane does not have sewerage systems and on-site sewerage disposal or septic tanks are often poorly designed. Further, contributing to the problems in urban area with are now stagnant wastewater from households and some small industrial and other sector without treated with open road-side drains, flow directly into marsh or natural channels such a system will continue to have a detrimental impact on the public health by mixing sewerage in the storm drainage system”. There are 1,256 households discharged their sewage directly into the surface water and 501 households with no toilet at all within areas that are draining into Hong Ke and That Luang Marsh. As a result, the water quality in the drainage channels and wetlands of Vientiane has deteriorated. This water is used and reused for many purposes including peri-urban agriculture. Eventually this water flows into the Mekong and potentially affects many communities downstream of Vientiane.