The Department of Irrigation began opening spill gates at multiple reservoirs across the country on Thursday evening as heavy rainfall pushed catchments beyond holding capacity, with Deduru Oya, Inginimitiya and Tabbowa reservoirs all releasing significant volumes of water into downstream basins.
By 7.30 p.m. on Thursday, two spill gates of the Deduru Oya Reservoir were reopened by one foot each, the Wariyapola Regional Irrigation Engineer’s Office said, releasing about 1,400 cubic feet of water per second into the Deduru Oya itself.
At Inginimitiya, several spill gates were opened by around 7.00 p.m., the Director of Water Management at the Irrigation Department said. Two gates were opened by three feet each and another two by two feet each, discharging approximately 5,000 cubic feet of water per second into the Mee Oya.
At Tabbowa, eight spill gates were opened — four by three feet each and four by two feet each — releasing about 4,400 cubic feet per second, also into the Mee Oya.
The Department of Irrigation urged residents in downstream areas of the Inginimitiya and Tabbowa reservoirs, particularly along the Mee Oya basin, to remain vigilant as water levels may fluctuate.
Separately, engineers in charge of the Wimalasurendra Reservoir confirmed that it began overflowing on Thursday afternoon following heavy rainfall in the Norton Bridge area. The overflow has caused a slight rise in the Kehelgamu Oya, a key tributary in the upper Kelani basin and one of the Castlereigh-Maussakelle hydropower complex’s downstream catchments.
The new openings come on top of the 37-plus reservoirs already at overflow level flagged by the Disaster Management Centre earlier on Thursday, and follow the 33 reservoirs found spilling on Wednesday. They line up with the low-pressure system over the southwest Bay of Bengal that has driven Sri Lanka’s worst inland flood risk in months, with NBRO landslide warnings extended across multiple districts into Friday.
Source: Ada Derana.
