The estimate, however, is premised on the assumption that it does not rain within the period.
DPWH Secretary Gregorio Vigilar has pleaded for more understanding from those badly affected, saying that "the ultimate solution" is at hand. He referred to the P3.2 billion North Lakeshore Dike Project stretching from Lower Bicutan in Taguig to the Mangahan Floodway in Pasig.
"We hope we don’t get heavy rains failing within the next three weeks. We expect to see those low-lying areas finally free of floodwaters in more or less 18 days if it does not rain," DPWH National Capital Region director Salvador Pleyto said yesterday.
The floodwaters in those areas, from heavy rains brought by typhoons "Reming" and "Seniang" which hit the country two months ago, have not receded as fast as expected, causing havoc on the lives of hundreds of affected residents until today. Reming caused the lakewater level to rise 1.5 meters while Seniang raised it by about another meter.
Pleyto explained that the recent intermittent heavy downpours have worsened the situation. "In addition, it is taking some time for the lake to flush itself of excess water because while there are about 113 tributaries draining into the lake, it only has one outlet, only the Pasig River," Pleyto said.
Of the 113 tributaries, 21 are big rivers coming from Quezon, Batangas, Rizal and Laguna provinces.
"Most tributary rivers and creeks are located in Laguna. So, even if there are no rains in Rizal, if it rains in Laguna, the effect of the rising of the Laguna lake waters will be felt everywhere around it," Pleyto said.
The official also trotted out records showing that when the Mangahan Floodway and Napindan Hydraulic Control were not yet in place, the floods in the Laguna Lake area reached even higher levels than the most recent, which registered 13.39 meters after Typhoon "Seniang".
Records showed that the highest level reached sometime in 1919 was 14.62 meters above normal level.