River Management

Advantages of dams and reservoirs

* Multi-purpose can be used for energy production (HEP) and water storage as well as flood control
* Provides opportunities for recreation: Water sports, fishing
* Reservoirs can attract tourists.

Disadvantages of dams and reservoirs

* Expensive
* Loss of farmland and homes due to reservoir creation
* Displacement of people
* Affects on ecosystems: can affect fish breeding
* Dams trap sediment which means the reservoir can hold less water.


* Habitats are flooded often leading to rotting vegetation.
* releases methane which is a **greenhouse gas**.

Advantages of channel straightening

* Speeds up the movement of water over a short distance
* More water can be held in the channel.
* it can be used to reduce flood risk in built-up areas.

Disadvantages of channel straightning

* May increase flood risk downstream as the discharge reaches those areas more quickly
* Expensive 
* Dredging needs to be done frequently.
* Affects river ecosystems due to changes in velocity

Advantages of embankments / levees

* Increased river capacity means it is less likely to flood
* New river bank habitats may be created

Disadvantage of embankments / levees

* Visually unattractive particularly if made from concrete
* May fail and lead to more serious flooding

Advantages of flood relief channels

* Effective in reducing the flood risk in high value areas
* New habitats may be created 
* Insurance costs may be reduced for people living nearby

Disadvantages of flood relief channel

* Expensive
* Regular maintenance is needed
* Disruption to existing habitats
* Can be visually unattractive
* If water levels continue to rise, the relief channel may also flood.

Advantages of flood warning and preperation

Disadvantage of flood warnings and preperation

Advantage of flood plain zoning

Disadvantages of flood plain zoning

Advantages of planting trees

Disadvantages of planting trees

Advantages of river restoration

Disadvantages of river restoration