MARGAO: Amid growing concerns regarding the deteriorating condition of River Sal, including issues related to pollution and the quality of desilting and aeration projects, officials from the Water Resources Department (WRD) say they have been taking measures to rejuvenate the river.
“The department has conducted desk studies, focusing on hydrology, hydraulics, soil erosion, groundwater, and improvements to earthen banks, among other aspects, to enhance ground and surface water, flood control, and bank erosion control. We have devised a holistic plan that will be implemented in phases,” explained Minister for Water Resources, Subhash Shirodkar.
The WRD has collaborated with the River Rejuvenation Committee (RRC-Goa), established by the Department of Environment, Goa, under the chairmanship of the Secretary of Environment, to prepare an action plan for the restoration of a segment of the Sal River.
The initial phases involve enhancing the river’s hydraulic capacity through desilting and channel improvements, covering a length of 19.77 kilometres from its origin to Lourdes Chapel-Navelim, including its tributaries, said officials from the WRD.
The restoration work involves the removal of accumulated silt and debris to increase the river’s carrying capacity. Additionally, a three-year maintenance period is included in the contract to ensure the river remains free of obstructions and silt, with the agency responsible for ongoing
The second phase focuses on improving water quality. This entails constructing storage structures (bhandaras) and installing an aeration system near the fish market, equipped with an automated gate to control water levels. The stored water undergoes aeration using floating aerators to enhance Dissolved Oxygen (DO), reduce Biological Oxygen Demand (BOD), and enhance physical parameters such as turbidity, colour and odour, while also providing bio-beds.
Steps to safeguard the biodiversity in the villages along the riverbanks, are being carried out by village-level biodiversity management committees. Minister Shirodkar referred to an ongoing sand mining impact assessment study report conducted by the Goa State Biodiversity Board (GSBB) in collaboration with CSIR-NIO. This study includes river biodiversity indices and environmental management plans, with a focus on documenting river biodiversity.
Concerns about sewage pollution from the Sewerage Treatment Plant (STP) in Shirvordem-Navelim, are being investigated by the PWD and the Sewerage & Infrastructural Development Corporation of Goa Ltd (SIDCGL), said WRD officials. An Online Continuous Effluent Monitoring System (OCEMS) has been installed at the 20 MLD STP in Shirvodem to monitor treated water quality before discharge into the Sal River. Currently, OCEMS is undergoing trial runs.