Pangsinan (outlined in red) (Image from Google Maps)
VILLASIS, Pangasinan — Panic gripped residents living in towns along the Agno River following social media posts which warned that the San Roque Dam in San Manuel town would release a huge volume of water on Saturday night when Typhoon “Ompong” (internationally known as “Mangkhut”) exited the country.
Virgilio Maganes, a resident of Barangay San Blas, said he received messages from worried friends and relatives from 7 p.m. on Saturday to 5 a.m. Sunday about the message posted by Ricardo Revita, former Rosales town mayor. The message was shared more than 1,000 times.
The former official urged residents in low-lying areas along the Agno River to evacuate, saying the dam’s water level was rising fast and a big volume of water equivalent to water spilled in 2009 would be discharged.
Revita referred to the San Roque Dam incident which submerged 39 Pangasinan towns and cities.
“Move to higher places. Don’t panic. There is still time,” Revita said in his post.
Maganes said his sister and her family packed up and were about to go to an evacuation center. Then his sister called him. A friend from another village, he said, also asked him if it was true that a dike had breached in one of this town’s villages.
“I had to explain to them that the water that would be released by the dam would not be that big,” Maganes said.
Roderick Mina, the town’s planning and development officer, said they had to call the village chiefs to assure them there was no need to panic.
Two teams went around the six villages along the Agno River to calm residents.
Revita later posted photos showing that he had moved his things to the second floor of his house in Rosales.
A “northern Luzon advisory” posted by a Cagayan Economic Zone Authority official, who is from Mangaldan town, also warned of flooding in eastern and central and Pangasinan towns because of the “big” volume of water being released by the dam.
The official told residents near the riverbanks to move to safe areas and evacuation centers, and his post was shared more than 1,400 times.
At 2 p.m. on Saturday, the National Power Corp. (Napocor) announced that it was opening San Roque Dam’s spillway gates due to the huge inflows to the dam that included water spilled by the Ambuclao and Binga dams which are upstream of the Agno River.
Following the Napocor announcement, Gov. Amado Espino III immediately ordered the forced evacuation of residents living in villages along the river.
Odette Rivero, Napocor spokesperson, said two of the dam’s spillway gates were raised by 1 meter each at 5 p.m. to spill water at the rate of 582 cubic meters per second. One cubic meter of water is equivalent to five drums of water.
The volume of water released was gradually increased until it reached 2,428 cubic meters per second at midnight. At 6 a.m. Sunday, the outflow had gone down to 1,691 cubic meters per second.
“Despite the peak inflow starting 5 p.m. at 6,130 cubic meters per second, peak outflow from 11 p.m. on Saturday to 2 a.m. Sunday was only 2.400 cubic meters per second.. This means that the dam is striving to contain the huge water volume rather than releasing them at once,” said Rivero.
On Sunday morning, Revita apologized to netizens.
“Many of you may have panicked, but I did it in good faith to give you timely and correct information for you to be able to prepare,” Revita said.
He said that everybody must be thankful that what happened in 2009 did not happen again.
Revita also thanked Napocor for managing the water discharge in order to make it “less destructive.” /atm