Urban development in Metro Manila has reduced the number of green open spaces which absorb rainfall, leading to flooding undersized drainage systems cannot handle. Current systems are based on the flood levels of previous decades, and require better solution.
During the flash flood and heavy storm rain city/municipality road, commercial areas and residential areas are heavy flooded in just a minute that rises from 1ft to 5ft height of water, and sometimes flood last for days or months to subside.
- The rivers stream extremely rises and overflows in the city/municipalities.
- Water drainage cannot absorb flood load in spite of reclogging or rehabilitation programs.
- The sea level is much higher than the downstream river which prevents or slows down the outflow.
- The flooding pumping design is not effective or incorrectly designed.
- Storm drain system cannot cope up rapid runoff during flash flood or heavy storm
- Groundwater Aquifer are damage and depleted the capacity to absorb surface water
GROUNDWATER as flood control
Earth’s Hydrological Cycle
Throughout the decades different flood control technologies have been designed and constructed, despite Billions of pesos budget spent by the Philippines Government
unfortunately until now no solution has come effective (flood gate, Estero dredging, storm drain catch basin), the Filipino people still suffer: cause human lives, health, and damage to properties, and have a great impact on our economy
Some of the existing Flood Solutions are only temporarily designed as stormdrain storage basins but when heavy rain lasts for several days and massive flash floods it will not cope up and tend to overflow.
The existing conventional solution is the city flood drainage flows into the river and when the river rises to maximum level it will backflow (back) to the city drain causing the flood to rise up.
Heavy rain that lasts for several days in the catch basin, stormwater storage, and floodgate are not enough to prevent the rising of the flood water, to some extent city drainage flows to rivers where water level rise tends to backflow