The Chao Phraya Dam in Chai Nat province reduced its water discharge rate to 3,149 cubic metres per second on Friday morning, a drop of 31 cubic metres per second.
Residents downstream in Ayutthaya province who have been flooded by the release of excess water have called on the Royal Irrigation Department to reduce the daily discharge rate to alleviate their hardship.
On Thursday night, the dam discharged water downstream at 3,180 cubic metres per second before reducing the discharge rate to 3,149 on Friday.
Ayutthaya authorities reported flooding in 992 villages in 156 tambons of 14 districts in the central province, affecting 67,580 households.