While the insufficient storage position in the Mettur dam and consequent delay in releasing water for irrigation have dealt a heavy blow to farmers of the delta, it has provided an extended window to Public Works Department to expedite the construction of the check dam across the Cauvery river near Tiruchi.
Construction of the structure near Kambarasampettai in the city is underway at a rapid pace now and according to sources about 43 per cent of the work has been completed so far. The progress is way above the expectations when the work started in March as then the PWD was racing against time to complete as much foundation work as possible before the usual Mettur opening date of June 12.
But as the dam could not be opened due to insufficient storage, the PWD has already got a month’s extra time and if the window period extends for the next 30 to 45 days, about 60 per cent of the work could be completed, sources indicated.
The work, however, could slow down a bit if water were to be released in the Cauvery in view of the Adi Perukku. Indications are that the PWD would try to enclose the work site by putting up temporary bunds to divert the water on one side of the river.
The check dam was sanctioned at a cost of Rs.32 crore following a public outcry in the past few years over heavy exploitation of the river bed for several drinking water schemes catering to the needs of various cities and towns as far as Ramanathapuram. Chief Minister Jayalalithaa had laid the foundation stone for the project in June last year.
Farmers of the region and city residents had sought the check dam to help improve ground water table and recharge water sources on the river bed.
Currently work is nearing completion on the construction of cut-off diaphragm walls. Fifty per cent of works on the apron has been completed.
The check dam, coming up close to Tiruchi Corporation’s main pumping station and collector wells of Ramanathapuram water scheme, is located about 100 metres upstream of Amma Mandapam bathing ghat on the left bank of the Cauvery.
The structure would run for a length of 540 metres and stand about 1.5 metres in height from the bed level. It would head up water for a stretch of 1.50 km upstream and provide a continuous wetting of the river bed so as to keep the drinking water collector wells sufficiently recharged, especially in the summer.
The check dam is expected to help recharge ground water table for a radius of about four to five km.
