Annual Maintenance Contract Of Replacement Of Wornout Di Air Valves On 1600 &1400Mm Dia Godavari Pumping / Gravity Main From Narava To Tsr Complex, Repairs, Reconditioning And Maintenance Of Damaged Existing Suitable Ci, Di D/F Gear Wheel Type Sluice Valves In 33.00 Mgd Wtp And 42.00 Mld Wtp At Narava Under Ae (Ws)-Hwws Section In Gvmc, Visakhapatnam For The Year 2025-2026