The incident on Tuesday where two shops fell into the Idukki reservoir at Kallarkutty on the Adimali- Kumily National Highway has highlighted the need to restrict encroachments of areas that come under water streams in the High Ranges. Encroachments of rivers and water streams is still rampant in the Periyar downstream of the Idukki arch dam.
Considering the topography of the High Ranges and the sensitivity of the area to landslips, local bodies should have taken strong measures against small-scale encroachments. Almost all the rivers in the High Ranges have been encroached upon and side walls that had been constructed to limit the flow have been pulled down, often leading to inundation during the monsoon.
The encroachment of rivers and construction of buildings are more rampant near the main towns and junctions. The two shops that were washed away were built on loose soil filled for construction. Had necessary measures been taken considering the sensitivity of soil piping, the landslips could have been averted.
Encroachment of rivers
Unauthorised constructions are rampant on the Periyar downstream of the Idukki arch dam. Even government buildings have come up in this region. In the event of the opening of the dam shutters of the Cheruthoni dam, the constructions and farmlands will go under water.
``Even if a stream is blocked for the constriction of dam or check dams, its downstream areas should be protected from encroachments as the river water is expected to flow its course when the dam shutters are opened,” said an official of the KSEB. He said there was a ban on constructions in the downstream area of the dam. However, permission had been granted for constructions in Cheruthoni close to the Cheruthoni dam and Idukki arch dam.
The majority of constructions on the river banks were undertaken by filling the land. When landslips occur and river waters increase during the monsoon, they face the danger of a natural calamity.
Idukki is a climate sensitive area and a cloudburst a few years back at Elamala, one of the highest peaks where cardamom is cultivated, had caused heavy damage. “Heavy rainfall could occur in a short duration of time. “We should impose strong restrictions on filling the water stream areas and restrict development works on the grasslands,'' said G. Sudarsan, an ecologist.
