People living in the delta region along the Prek Tnaot River in Kampong Speu province should be on the lookout for flash floods as water levels in some large reservoirs have risen above caution levels and water resources officials have opened some sluice gates to gradually release water in order to prevent the dams from being overtopped or breached.
Nhanh Cheab Hung, director of the provincial Department of Water Resources and Meteorology, told The Post on May 2 that due to the continuous heavy-to-moderate rains in recent days, the water levels in some large reservoirs – such as Ralaing Chey in Samrong Tong district’s Kaheng commune, Khpob Krous in Baset district’s Preah Khe commune, and Chan Thnal in Odong district’s Kraing Chek commune – have risen past the point where opening the sluice gates is required to try to control the flow of water and guard against greater disasters.
“Currently, rain continues to fall in parts of Phnom Sruoch, Baset, Oral and Chbar Mon districts. Most of the rice fields are completely saturated with water already and it now flows into the Prek Tnaot River, which is raising the river’s water levels so high at the reservoir that it is overtopping the dam, which requires us to open the floodgates at the top to let water flow down to the bottom,” he said.
According to Cheab Hung, the Prek Ralaing Chrey dam is 12m long and has five gates which are now opened to a height of 0.5m to allow the water to flow slowly outwards to prevent flooding in parts of the Prek Tnaot River delta in the upper part of Kampong Speu province.
Some reservoir dams in Baset district are also expected to have their waters rise above the caution level and flow over the back of the spillway into the Slako River along National Road 3.
Samrong Tong district governor Sim Rattanak told The Post that the water situation in the delta of the Prek Tnaot River in his district has not caused any major concerns due to the presence of wide canals there, which can help to release a large part of the water from Prek Tnaot River while the drainage from the large reservoirs at the top of the dams remains limited.
“This year, it has been raining heavily since the beginning of the season and the fields have been flooded, but there is still no cause for concern. However, our authorities need to monitor the water situation and educate people to be more vigilant about possible floods,” he said.
On the afternoon of May 2, the waters of the Prek Tnaot River overtopped the Prampi Makara dam on the outskirts of the capital and flowed down the spillways into the Prek Tnaot delta downriver from the dam, according to Phnom Penh municipal water resources department director Mao Bunthoeun.
“The water level in the Prek Tnaot River in Phnom Penh is constantly increasing, which requires people in the delta along the river to be very careful because the rain continues to fall,” he said.
According to Bunthoeun, the Prek Tnaot River delta dams – both the large and the small levees –have a total length of 8.6km and have already been upgraded, while the 2,815m-long canal that is 20m to 30m wide and flows from drainage Pumping Station Five to Boeung Tumpun’s pumping station has been rehabilitated in order to relieve the flooding of people’s houses in that area during the rainy season.
Bunthoeun stated that the canal can play an important role in relieving flooding in parts of Dangkor, Por Sen Chey and Meanchey districts of Phnom Penh by draining water from these areas into the Tonle Bassac River through the main canals of Boeung Choeung Ek, Chrov River and Prek Tnaot River.
According to the water level forecast for Prek Tnaot River by the Ministry of Water Resources and Meteorology on May 1, at Peam Khlai station the water level is 3.36m – an 0.80m increase compared to April 30.
At Ralaing Chrey dam, the water level in front of the door is 7.32m, which overtops the height of the closed door by 0.32m already.
At Prampi Makara Dam, the water level in front of the gate is 4.96m, which sends 0.16m onto the spillway. The water level behind the gate is 1.60m – an increase of 0.40m from April 30. The height difference between the front and back of the gate is 6.36m.
In Preah Vihear province’s Chheb district, local authorities reported that floodwaters inundated many houses – sometimes knee-deep, sometimes ankle-deep, but it did not cause any appreciable damage to crops or property. No lives were lost.
Chheb district police chief Srey Voleak told The Post on May 2 that heavy rain caused the flooding of more than 20 houses in Chbeb Keut village, but the water levels had receded gradually once the rain stopped.
“At this time, the weather is still gloomy and there is still light rain. However, our authorities have already prepared emergency personnel and materials in order to quickly rescue any villagers in danger and bring them to safety if the heavier rain resumes and we get more severe flooding,” he said.