BANK PROTECTION FOR VENNAR RIVER

The PWD Tamil Nadu, decided to go for an innovative method of providing a gabion structure in order to protect the river bank as well as to control erosion of the river bed. The method adopted was flexible, durable and self draining compared to conventional RCC retaining walls and also served as a permanent solution for sliding of the river bank. The client and contractor were convinced by the technical advantages and cost effectiveness of the proposed solution of using gabions. The bank protection works were executed using gabions for a stretch of 500 metres on either banks of Vennar river. The protection measures were required at three stretches. Gabion retention of 4.5m height was designed based on site conditions and launching apron 0.3m thick and 4m wide using mattress was provided for scour protection. After completion of the works the intended purposes were met. The gabion structure withstood two complete irrigation periods and settlements were not observed. The structure also ensured uninterrupted supply of irrigational water during monsoon season to an extent of 94,740 hectares of land in the lower reaches of Vennar river. The approach road over the retention structure established connectivity between Kalanjeri, Konur, Kovathukudi villages.