Laguna Lake showing abnormal rise of water

MANILA, Philippines - The Laguna Lake’s water level has risen abnormally, threatening to further inundate some eastern Metro Manila towns especially as a super typhoon looms.

Jun Mystica, officer-in-charge of the Laguna Lake Development Authority’s special concerns division-shore land management program, told The STAR of the “abnormal rising of the lake water” to 13.81 meters at the height of tropical storm “Ondoy’s” onslaught in Luzon last Saturday from its normal level of 12.5 meters. The water level went down to 13.33 meters as of 3 p.m. yesterday.

He said a huge volume of the lake’s water moved “landward” and flooded many outlying communities, including those that had never experienced flood before.

Mystica said the “slow recession” of the water in the lake has left many communities still under water since Saturday.

“What happened last Saturday was not the normal rising of the lake water but an abnormal rising of the lake water, which was not expected,” Mystica said.

He said the previous times that the Laguna Lake breached the 12.5-meter average level were in 1978 at 13.58 meters and in 1919 at 14.62 meters, also during typhoons.

Mystica said the arrival of super typhoon “Pepeng” might push the lake’s water level to 14.62 meters or more.

“It is not far-fetched that Laguna Lake’s water would reach that highest point in history or that the so-called 100-year phenomenon would occur,” he said.

“Although we don’t expect it to happen sooner since it is supposed to happen by 2019, it could be that the rise in the water level of the lake now is just the start of a possible trickle effect,” Mystica pointed out.

He said the volume of water that the Marikina watershed brings to the Marikina River is 3,300 cubic meters per second “at peak flood flow” while the Pasig River could only catch around 600 cubic meters per second of water.

Laguna Lake, he said, can only hold a little more than two billion liters of water.

“There really is some choking. Flooding is inevitable since water from Marikina River flows towards the Pasig River,” Mystica explained.

“And then there’s slower receding of water from Laguna Lake because from Saturday, the water decreased only by 0.48 meters,” he said.

“It could be that the volume of water that went to Laguna Lake was really big and if there are more rains over the watershed areas within the Laguna de Bay basin (including Metro Manila, Laguna and Rizal), then there will really be slower receding of water in Laguna Lake,” he said.

“Possibly because of this, certain areas in the eastern portion of Metro Manila remain submerged in water.”

In a separate interview, Gerry Carandang of the public information office of the LLDA said the abnormal rise in the water level of Laguna Lake displaced around 100,000 households in Lupang Arenda in Taytay, Cainta and Pasig.

Carandang said that the LLDA has repeatedly warned the communities in Lupang Arenda of the risk of flooding.

He said the residents ignored their warning and claim they have been paying fees to the National Housing Authority for “permit to stay” in the reclaimed area.

Fish pen ban

Meanwhile, Environment Secretary Lito Atienza on Wednesday ordered the LLDA to impose a total ban on the repair or reconstruction of fish pens and other structures in Laguna Bay that had been damaged by Ondoy.

He said Ondoy’s onslaught was a “welcome help” in efforts to rid the lake of structures that caused pollution.

He also scored the LLDA for its “inability to take control of the lake.”

“I have personally instructed LLDA General Manager Edgar Manda to make sure that destroyed, including submerged, fishpens will not be allowed to be repaired or reconstructed by their operators and owners,” Atienza said.

He said nature did “the gargantuan work for us in liberating the lake of fish pens and fish cages” and that it is now imperative for the LLDA “to learn from typhoon Ondoy’s lessons.”

While climate change was also to blame for the disaster, Atienza said the people’s improper disposal of garbage as well as their building of structures in the lake exacerbated the situation.