With changes in weather pattern posing a serious threat to the safety of people, environmental organisations have urged the government to reduce the water storage capacity of Banasura Sagar and Karapuzha dams, the two largest earthen dams in the State, till October end to reduce risks of disasters.
Addressing the media, Wayanad Prakruthi Samrakshana Samiti president N. Badusha said people in the district had been denied the benefits of the Banasura Sagar dam of the KSEB at Padinharethara, “as water was not provided for irrigation purposes owing to apathy on the part of the Irrigation department.”
Deluge has become so common during the monsoon after the commissioning of the dam a decade ago, and it submerges nearly 10,000 acres belonging to farmers living downstream of the reservoir. Moreover, the KSEB is yet to provide compensation to farmers who suffered losses, he alleged.
Though hundreds of families, including tribal families, were evicted for the construction of the Karapuzha reservoir and close to ₹500 crore had been spent for the project in 30 years, it was yet to be fully commissioned, Mr. Badusha said.
A leak detected on the left baseline of the dam near a pipe from the infiltration gallery had raised concern among those residing near the site a few years ago.
Since the catchment areas of the reservoir had been experiencing heavy rain similar to cloud burst for the past several years, officials are forced to raise shutters during the monsoon.
The hill slope of the Banasura mountain is the major catchment area of the reservoir, which recorded a rainfall of 391 mm on August 8 and 438 mm on August 9, he added.
The ecologically fragile areas were shown as ‘red category’ zone in the zonation map of the National Centre for Earth Studies. A cloud burst in the area would result in landslips on hill slopes, and earthen dams would not bear their impact.
A similar situation arose in the Coorg mountain ranges in 2012, and the debris of the landslip reached Pazhassi dam in Kannur district, resulting in overflow of water. However, it did not impact the dam, as it was made of concrete.
An expert committee should be constituted to study the conditions of the dams and their storage capacity should be reduced till the completion of the study, he said.