Navigation channels and tidal power plants (250 mw) for Chennai City

The Chennai City is blessed with rivers of Adayar, Coovum, Kortralaiyar, Ennore creek, Araniyar Rivers, Pulicat Lake and interconnecting Buckingham canal. Training walls of 2500 m lengths, with submerged barrages at about 500 m inside the entrances are to be constructed to generate rip currents, which prevent deposition of sedimentation and mouth closure by littoral drifts. A navigation channel in the Coovum River of 70 m width to 64 km long to Thiruvallore may be constructed with 5 lock and gate systems to rise and lowering boats and barrages. Another navigation channel for 36 km long in the Adayar valley up to Karisangal village may be constructed in similar manner. The entries of tidal waters far into Thiruverkadu, Thiruneermalai, and Buckingham canal flush out sewerages far into the sea. The dredging and deepening of these waterways -3 m msl always allow groundwater seepages enhancing river discharge potential. Disposal of sewerages and waste waters further increase this potential. Beyond these tidal basins, both Coovum and Adayar valleys, dredging up to 5 m depth is sufficient. Below the valley floor sufficient groundwater seepage enhance waters for navigations in these water ways. Construction of lock and gates at suitable places always maintain sufficient water level for navigation. Using volume of specific yield of groundwater supply (>10 l/s), river water and sewerage discharges, assumed potential of river-discharges and tidal prisms of saline water are calculated. The volume of water discharge of tidal prism has potential to generate 250 MW power by constructing suitable barrage type of tidal power plants at the mouths of Coovum, Adayar, Muthukkadu, Ennore Creek, Karungali and Thangaperumbalam near old Pulicat Lake. These plants can work for 20 hours per day. To reduce environmental problems plants may be constructed following the model of Severn Tidal Power Plant in United Kingdom.