The Flood Action Plan (FAP) relies on huge levees along the rivers’ length. At an estimated US$10 x10^9 they could take 100 years to build. Up to 8000 km of levees are planned for the 1600 km of river in Bangladesh. They are not able to withstand the most severe flooding, such as in 1987, 1998 or 2007. The embankments contain sluices to reduce water flow and to control damage caused by flooding.
They are set back from the river, which protects them from constant erosion and is also cheaper to install.
The FAP still has many issues:
- Increased time of flooding, since embankments prevent back flow into the river
- River channelization by levees may increase the risk of flooding downstream and in the area between the levees
- Channelisation will also increase deposition between levees rather than on the floodplain, which has been seen to be an issue in Lousiana during Hurricane Katrina
- Not enough sluices have been built to control the level of floodwater in rivers. There may be increased damage to land if embankments are breached
- Sudden breaches of embankments may also deposit deep layers of infertile sand reducing soil fertility and affecting agriculture
- Compartmentalisation of the drainage basin may reduce the flushing effect of floodwaters to remove pollutants
- By preventing back flow to the river, areas of stagnant water will be created which may increase the risk of diseases related to water supply
- embankments may cause wetlands to dry out, losing biodiversity
- Decreased flooding will reduce the number of fish, which is a major source of protein
The rivers are largely controlled by factors outside the country. Floods in Bangladesh are also not just related to rivers, and the rivers are needed for agriculture and other industries.
The FAP has overall led to social, environmental and economic issues within the Bangladeshi population.