MANILA, Philippines ? At least 400,000 squatters blocking key drainage channels of Laguna Lake on the edge of Metro Manila need to be relocated to fix the flooding crisis in the metropolis, the Laguna Lake Development Authority (LLDA) said Thursday.

The squatters are among a million people living on the shoreline of the country?s biggest lake, which will stay flooded for up to five months unless drastic action is taken, LLDA chief Edgardo Manda said.

?I have made a strong recommendation to remove these people from the danger zones and not allow them to go back,? Manda said of the 400,000 squatters who are living mostly on what was once marshy wetlands.

To keep the people out, authorities would probably need to erect barricades and station sentries in these areas, he said.

The recommendation came as large parts of the eastern part of Metro Manila remain flooded 12 days after Tropical Storm ?Ondoy? (international codename: Ketsana) dumped the heaviest rains in more than four decades on the city, killing nearly 300 people.

Laguna Lake, whose water level has risen by at least 10 feet, has submerged hundreds of villages in 18 towns and two cities in Laguna province, making these uninhabitable for more than 700,000 people, according to a Church group.

Manda and other officials have acknowledged that chaotic urban planning, or no planning at all, exacerbated the crisis, particularly around Laguna, where shantytowns, factories and housing developments have overtaken farms.

Political decision

But Manda said he realized removing squatters from around the lake would be a ?political decision? that may not sit well with politicians so close to national elections in May.

About 300,000 of the squatters are living in and around an illegal open garbage dump on wetlands that block two connecting rivers that are meant to channel excess water from the lake into Manila Bay to the west.

?The channel is constricted,? Manda said, adding that clearing the squatters and garbage from the wetlands was key to allowing water to flow more freely.

House on stilts

About 100,000 other squatters live in houses on stilts on the lakeshore to the south, he added.

Aside from the one million people living near the immediate shoreline, which is likely to remain flooded for many months, at least one million others live in adjacent districts of eastern Manila that are also still under water.

A fisher folk group claimed that villages surrounding the lake were already submerged even before Ondoy struck.

Quoting reports from its field coordinators in Rizal and Laguna provinces, the Pambansang Lakas ng Kilusang Mamamalakaya ng Pilipinas (Pamalakaya) Thursday said lakeshore residents had noticed that water had already breached the shores of their villages on Sept. 26.

?The disaster was bound to happen,? Pamalakaya national chair Fernando Hicap said in a statement.

Napindan control closed

Hicap described the arrival of Ondoy as a ?perfect storm in the making? because the LLDA refused to open the Napindan Hydraulic Control Structure (NHCS) that would release excess waters in the lake.

The Pamalakaya official said his group had been sending numerous notices to Manda that the LLDA should open NHCS to prevent floods around the lake and in Metro Manila.

The NHCS was built in 1983 to prevent or lessen the increase of salinity from Manila Bay and pollution from the Pasig River from entering Laguna Lake during times of reverse flow.

Confluence of rivers

The NHCS is found on the confluence of the Marikina and Pateros-Taguig rivers with the Pasig River. This confluence is also the downstream endpoint of the Napindan Channel, which is the upper part of the Pasig River that connects to Laguna Lake.

Aside from preventing the reverse flow of Pasig River, the NHCS is also used for flood control.

During rainy season, most of the flooding along the Pasig River area is due to the increased water flow from the Marikina River.

Hicap noted that the Manggahan Floodway in Pasig City was constructed to divert much of the excess water from the Marikina River directly into Laguna Lake.

?By also closing the NHCS during times of rain, the water is effectively dammed in Laguna de Bay, preventing it from flooding the downstream portions of Pasig River,? he pointed out.

Dredging Pasig

Executive Secretary Eduardo Ermita announced on Wednesday that a Belgian firm had been hired to dredge the Pasig River.

?Definitely this will help,? Ermita said, but he did not address the issue of the squatters directly.

He also said the government was reviewing the process of granting permits to developers of residential areas along the 220-kilometer stretch of Laguna Lake shoreline that were now partly submerged.

?These things must be looked into because we can see the effects,? he told reporters.

Aside from working out a way to unplug the lake area, the government has been trying to care for more than 315,000 homeless flood survivors who remain in schools, sports arenas and other makeshift evacuation centers.

Probe

At the House of Representatives, Muntinlupa Rep. Rufino Biazon filed a bill calling on lawmakers to look into the state of Laguna Lake and to come up with ways to address the flooding of its lakeshore communities and other nearby areas.

Other lawmakers called either for an inquiry into the activities of the LLDA or to give it more powers to go after those polluting the lake.

Anakpawis party-list Rep. Rafael Mariano said the LLDA?s fishpen development project should be given a second look because, according to him, the corporate fishpens covering the lake were partly responsible for blocking the flow of water to the floodway.

Laguna Rep. Edgar San Luis, in a privilege speech delivered on Monday, pushed for the passage of a bill that would give the LLDA its own police force, among others, so that it would cease to be a ?paper tiger.? Reports from Agence France-Presse; TJ Burgonio and Leila B. Salaverria in Manila; and Delfin T. Mallari Jr., Inquirer Southern Luzon