banasura sagar dam bangalore bangalore rural district bangalore water supply and sewerage board bay of bengal bhavani river chinnar river erode grand anicut hemavati river honnuhole river kabini river kanakapura karnataka karur kaveri river kerala kodagu kumbakonam kushalanagara lakshmana tirtha river mayiladuthurai mettur dam mysore noyyal river pambar river puhar riparian zone shimsha shivanasamudra falls srirangam srirangapatna stanley reservoir talakad talakaveri tamil nadu tippagondanahalli reservoir tiruchirapalli western ghats