According to reports, half a million people have been displaced and more than 7,500 houses have been damaged.
Water levels seem to be receding and the weather is said to be clearing.
“There was a good news on the receding water levels in rivers during the past 24 hours due to the low rainfall that ended at 3.30 pm,” the Irrigation Department said.
As the weather cleared, several thousand people who were evacuated over the weekend, returned home to clear debris and mud from their waterlogged homes. More than 80,000 others remained in relief camps as their homes were either destroyed or wiped out.
Director (Hydrology) P Hettiarachchi said the water levels in the Kalu Ganga and the Gin Ganga were decreasing.
The two rivers overflowing was the main reason for severe flooding more particularly in the southern Galle and Kalutara districts.
The government began efforts to purify wells and other potable water sources which were contaminated by the floods.
Sri Lanka had sought international assistance and India had sent three naval ships laden with supplies in the last a couple of days. Indian naval divers and medical teams joined in the rescue efforts in the flood-hit regions.
The Indian contingent comprised of more than 300 navy personnel.
India’s INS ‘Shardul’ had nearly 200 personnel on board, including specialised rescue, diving and medical teams, as well as a large amount of relief material and Gemini inflatable boats. INS ‘Kirch’ was carrying 125 personnel with more diving teams and relief supplies.
A third Indian naval ship arrived on Wednesday, which brought relief supplies including rice, lentils, sugar, milk and blankets for the displaced.
Several other countries also promised to help Sri Lanka to deal with the crisis. Pakistan and China will be sending relief ships and Australia said it would provide 500,000 dollars as aid.
(With inputs from agencies)