measures used to reduce the frequency and the magnitude of flooding. Two approaches: Hard engineering projects which build up banks, straighten and deepen channels, divert channels, build overflow channels or dam rivers altogether - all attempts to deal with large volumes of water which have already reached the channel. Soft engineering projects which involve afforestation or reforestation of the drainage basin or farming techniques which reduce surface run-off such as contour ploughing or stone lines - all attempt to deal with large volumes of water before they even get to the channel.