Various environmentalists and green organisations had earlier expressed their apprehensions over the effectiveness of the ban on Sand mining. They had alleged that the district authorities had failed to impose the orders effectively.

Though environmentalists had demanded stringent steps against illegal sand mining, the police and the patrolling team have failed to check the menace. Several country boats are engaged in mining activities in River Periyar, but little has borne results till now.

"Mining is rampant in Periyar, especially in places like Cheranalloor, Varapuzha and Eloor. They are smuggling sand to shelters at night, with the knowledge and support of the police," said a green activist. Mining is common even during daytime. Unrestrained removal of sand poses serious threats to major bridges on Periyar.

"If this is the state of affairs, the bridges will collapse and even the lift irrigation projects will be badly hit," said an activist of the River Protection Council.

It was on July 1 that the district administration imposed a ban on Sand mining during the monsoon season to facilitate the sand to reach the tailend of the rivers. According to district authorities, all the kadavus (Sand mining points) were closed by June 30 and has also warned that those who violate the ban will be prosecuted. The ban will continue till September 30.

The district authorities have also prohibited the removal of land-sand. To resume mining, removal and sale of sand, local bodies have to submit a study report by the Centre for Earth Studies.

Experts warn the ecology of the rivers would be affected due to sand mining during the rainy seasons. Due to the unrestrained mining of sand, the water-retaining capacity of the rivers has come down considerably and also, not much percolation takes place through the riverbeds, say experts.