Goa’s water resources department is planning to extend and upgrade the Selaulim–Kalay pipeline to Opa, with a proposed diameter increase to 900mm aimed at reducing transmission losses, corrosion-related bursts and seepage before water reaches treatment facilities.
The proposal follows approval for the availability of 50 million litres per day (MLD) of water for treatment at the proposed Opa Water Works. The department plans to extend the pipeline so that water from the Selaulim system can be discharged directly into the Khandepar river at Opa, reducing the distance and losses involved in the existing route.
According to the report, Selaulim dam currently releases 48 MLD into the Kalay river. However, only around 25–30 MLD reaches Opa. Water currently flows from the Kalay river by gravity into the Khandepar river before reaching Opa Water Works for treatment. The proposed alignment would change this arrangement by taking the pipeline closer to Opa.
WRD executive engineer Mario Rebello said the existing pipeline’s diameter is proposed to be increased to 900mm. The current pipeline, commissioned in 2002, is 13km long and has an 800mm diameter. It is made of mild steel and has been affected by corrosion, seepage and repeated bursts, according to the report.
The existing network includes six sluice valves and 36 air valves. These components support the operation and control of the pipeline, which carries Selaulim water towards the river system connected to Opa Water Works. The proposed expansion would increase the pipeline’s length to 31km.
The plan is also linked to the seasonal operation of the Selaulim water system. Four 600-horsepower pumps at the Selaulim dam campus are used to discharge 48 MLD into the Kalay river during summer, from mid-March until the monsoon. This flow is intended to rejuvenate the Khandepar river before the arrival of the rainy season.
Rebello said the number of pumps would remain unchanged under the proposal. The planned intervention would therefore focus on the conveyance system rather than increasing the pumping capacity at Selaulim dam.
The gap between the volume released at Selaulim and the quantity reaching Opa highlights the operational challenge facing the existing water route. The department’s proposal seeks to address that gap through a larger and longer pipeline, while replacing the current arrangement in which water moves through connected river stretches before treatment. Further details on the project’s cost, construction schedule, tendering process and implementation timeline were not provided in the report.