They generally revitalise the dead/buried drainage systems, the ephemeral streams become very active. Considerable area cultivated illegally in the bed of the buried/dead drainage system gets inundated. The good micro-environments in low lying areas are severely affected and productivity is lost. In addition the houses, roads and bridges also collapse.
Flash floods can be prevented by proper vegetative cover of these arid areas with suitable silvipasture system. The field bunds which are often supported by trenches should be covered with grasses on the bunds and trees in trenches. Cultivation near the ephemeral stream should be checked. The embankments of these streams should be strengthened with vegetative means. The bed of the dead/buried drainage system should never be cultivated. The Rashtriya Badh Ayog (RBA) or the National Commission of Floods, set up in 1976, believes that floods have increased in recent years because of human factors like deforestations, drainage congestion (caused by badly planned construction of bridges, roads, railway tracks, and other developmental activities), reduction in infiltration (because of increased occupation of land by industries and other developmental activities), reduction in infiltration (because of increased occupation of land by industries and large scale insanitation), and construction of embankments along rivers.
The flood-prone area in the country is over 40 million hectares, about one-eighth of India’s land area. The building of embankments was the only way floods could be controlled in the forties. The dams and reservoirs were considered useful to control runoff and reduce flooding.
Now there are several other measures to reduce the severity of flood. Felling of trees and deforestation on mountain slopes and in catchment areas need control. Weather forecast and flood warning systems be made a regular feature.