Over abstraction is the process of taking more water out of a river system than can be replenished naturally.
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Why is abstraction a problem for wild fish and their waters?
Lower volumes of water mean that fish are less able to migrate up and down rivers to complete their life cycles.
- Pollutants in the water become more concentrated because of the lack of dilution
- Increased sedimentation clogs up rivers because they do not have the energy to remove them.
- Less water results in reduced shelter and food availability for wild fish
- Water temperatures increase and oxygen levels decrease.