Case Study: Real-time information on salinity for agriculture and human health in Can Tho
Authors: ISET-International, Vietnam and Can Tho CCCO
Can Tho city is located in the centre of the Mekong Delta, with a population of over 1.2 million people. Most of the city’s land area of over 1400 km2 is comprised of agricultural land, although about two-thirds of the population lives in the densely populated urban areas. Only about 40% of all households have access to the city’s treated water distribution system, leaving nearly 60% of households—mostly in peri-urban and rural areas—to rely on other sources of water for drinking, cooking and other activities. According to a survey of 100 peri-urban households of Can Tho city in June 2013, households without access to piped water supply typically use multiple sources: river water, groundwater and bottled water. Poor communities in the peri-urban and rural areas of Can Tho are often dependent upon river water for both irrigating their crops, and also for domestic use. But water quality is a serious concern.
One of the factors affecting water quality is saline intrusion in the dry season (January – June), as seawater mixes with the river water and penetrates farther upstream during low flow conditions. Saline intrusion is a problem in many parts of the Mekong Delta, but had historically never been observed as far inland as Can Tho, which is 65 km from the open ocean. Salinity changes hourly with complex tidal flows in the many inter-linked canals and waterways of the delta. This makes it very difficult to predict when salinity levels will be dangerous in any given area.
In general, local communities in Can Tho were aware that salinity intrusion could have negative effects, but as it had yet not been an issue in Can Tho, they possessed little knowledge for how to modify their actions to deal with salinity.
ISET–International and CCCO Can Tho. (2016). Real-time information on salinity for agriculture and human health in Can Tho. Can Tho, Vietnam: Institute for Social and Environmental Transition-International.
The Rockefeller Foundation