Water levels at the Castlereigh and Maussakelle reservoirs have fallen sharply in recent days as prolonged dry weather grips the catchment areas on the western slopes of the central hills, engineers say.
As of 6:00 a.m. on Wednesday, the Maussakelle reservoir had dropped to 47 feet, while Castlereigh had fallen to 43.8 feet, according to reservoir engineers quoted by Newswire. The rapid decline has exposed previously submerged structures and small islands along the shoreline, a visible indicator of how far the water has retreated.
The drop carries direct consequences for Sri Lanka’s electricity generation mix. Water released from the two reservoirs feeds the Wimalasurendra, Laxapana, New Laxapana, Canyon and Polpitiya hydropower plants before flowing into the Kelani River. Lower reservoir levels mean reduced hydro output — and with it, greater reliance on more expensive thermal generation at a time when fuel imports are strained.
The timing compounds existing pressure on the power sector. The National System Operator (NSO) has already asked PUCSL for a further 15% electricity tariff hike on top of the 10% applied from April 1, citing revised dispatch costs. Reduced hydropower availability is a key driver of those revised generation cost forecasts.
The Department of Meteorology has forecast normal rainfall for May and June, but the inter-monsoon gap in April leaves the system exposed until wider rains arrive in the upcountry catchments.
