Vam Co Dong river starts from Cambodia, through Tay Ninh province and to Long An province: area of basin of 6.000 km2, the length through province of 145 km, the depth of 17 - 21 m. Thanks to water source passed from Dau Tieng lake with the flow of 18,5 m3/s, it supplements the irrigation for Duc Hue, Duc Hoa, Ben Luc districts and reduces the process of salinization of Vam Co Dong river through Soai Rap estuary. Vam Co Dong river connects with Vam Co Tay through horizontal channels and connects with Sai Gon, Dong Nai rivers by Thay Cai, An Ha, Rach Tra channels, Ben Luc river.
Vam Co Tay river with the length through province is 186 km, water source is mainly received from Tien river through Hong Ngu channel, satisfying the demand of irrigation for agricultural production and daily life of people.
Vam Co river with 35 km long, 400 m wide, emptying into Soai Rap estuary and flowing to the East Sea is the confluence of Vam Co Dong and Vam Co Tay rivers.
Rach Cat river (Can Giuoc River) situated in Long An province is 32 km long, with a small water flow in dry season and poor water quality due to receiving waste water source from urban area - Ho Chi Minh City, having a great effect on production and daily life of people.
In general, surface water source of Long An is not abundant, the quality of water is inappropriate in certain respects. Therefore, it does not meet the requirement of production and life.
According to assessment, reserves of ground water of Long An are not abundant and their quality is different and quite poor. Most of ground water source is in the depth from 50 - 400 meters under 2 horizones, Pliocene – Miocene.
However, the ground water source of province has many useful minerals which are exploited and served for daily life of people in the whole country.
In heavy rain or flood, with hurricane tide, it has often occurred flood in regions along the banks of river, especially lowland. To exploit efficiently surface water resource in Long An, in addition to channel expansion to create source, it is necessary to build more conservatoires in places where do not have sources.
In future, it is necessary to specify the reserves of ground water source, location, the reproductive capacity to have plan on effective and sustainable exploitation and use.