Dam Solutions

Is the dam necessary?

Before any decision is taken to build a dam for whatever purposes - public water supply, energy, irrigation, flood control - the first question that should be asked is: "Is the dam necessary?"

Although it is easy to assume that a dam will meet a real need, this is not always true. The decision-making framework set out by the World Commission on Dams can help deciding whether a dam is the best option, and if it is, how to move forward in a way that is economically sensisble, as well as socially and environmentally acceptable.

Increasingly there are also attempts by dam proponents to ensure that dams are built in a more sustainable way. An accurate needs assessment is essential. If a real demand has been established, then any dam which is subsequently built is also likely to be a better investment.

A needs assessment can show that a large dam may not be the best option. In many cases, demand side management - i.e. reducing the amount of water or electricity used by consumers - can mean that a dam may not be needed at all, that its construction can be delayed, or that alternative solutions are more suitable.

For example, irrigation systems utilised worldwide have water use efficiencies of only 38% and up to 1500 trillion litres of water are wasted annually.