Canals used to ease flooding pressure

Floodwater is being diverted through channels in a bid to help alleviate widespread devastation experienced in some Central Plains provinces.

The Royal Irrigation Department (RID) said yesterday less water has accumulated from the North flowed into the Chao Phraya River as it was passing Nakhon Sawan.

However, the river continued to surge because it was being filled with water from the overflowing Sakae Krang River in Uthai Thani. The Sakae Krang merges into the Chao Phraya before the latter reaches the Chao Phraya barrage, the main water level gauge, in Chai Nat.

RID director-general Prapit Chanma said water in the swelling Chao Phraya was being channelled into canals and waterways on both sides of the river before it gets to the Chao Phraya barrage.

The diversion was meant to reduce pressure on the barrage which was discharging 2,784 m³/s yesterday.

At the same time, the department was racing to push some of the water from the Chao Phraya into the Tha Chin River where tributary canals can be used to absorb the floodwater in the downstream Samut Sakhon province.

The diversion of water was being expedited through a system of water gates and large pumps put to work along designated stretches of the Tha Chin River.

Also yesterday, the Pasak River continued to burst its banks as it drew water from the Pasak Josasid Dam which was spilling water due to overcapacity. Water from the Pasak River was being partially channelled into Klong Rapeepat via the Narai watergate.

It then flows into the Rangsit Prayoon Sak, Bang Kanak and Phra Ong Chaiyanuchit canals before emptying into the Gulf of Thailand through the Bang Pakong River in Chachoengsao.

The channelling of water into canals was to prevent the Rama VI Dam from being overwhelmed by the Pasak River, which would further worsen flooding in low-lying areas of the provinces including Ayutthaya where floods have already wreaked havoc.

Mr Prapit said floodwater was also being diverted into large open fields able to store almost a combined 900 million cubic metres of water. The fields are located in the lower Chao Phraya River basin.