Flood Control

Flooding in the Philippines becomes prevalent as recorded in the past few decades. It happens in many ways which are mainly caused by abnormal atmospheric conditions known as global warming. Severe flooding creates not only extensive damage to property but also the possibility of loss of lives.

Extreme weather leads to some flood-causing occurrences creating massive water overflows in the low-lying affected communities. Tropical cyclone can produce huge amount of rains that can intensify flooding when it reaches land area. Heavy precipitation exceeds river capacities that leads to overflowing riverbanks. Flooding occurs when dikes are not built to sustain expected maximum level and strength of floods.

Rising sea levels may also cause floods along coastal communities. According to studies, the global mean sea level is expected to continue rising throughout the 21st century that may cause widespread property and socio-economic damage. The construction therefore of structurally stable walls or mega dikes is much necessary to inhibit entry of seawater during high tide.

The capacity of rivers to carry high water volume during floods must be increased to prevent bank overflows. Earth dikes of sufficient height and strength may be constructed as flood protection walls along riverbanks. Conventionally, dike slopes are protected using rigid concrete. But in most cases, earth movements caused by water infiltration and seepage simply create cracks and damages to the structure. 
Dike slopes can be stabilized using flexible concrete revetment. This prevents cracking since the structure simply follows soil movement while maintaining lateral stability. Interlocking blocks have interlocking components intended for this purpose. Long-rooted grass can be planted on its holes to provide massive root anchors and green appearance. Interlocking blocks are well suited in this kind of construction.

Polder dikes constructed along coastal banks may also use interlocking blocks to protect bare dike slopes. Polder dike which is mainly composed of earth embankments may be susceptible to scouring caused by wave forces and even ordinary tide transitions. A flexible revetment therefore is necessary to counteract these forces. Interlocking blocks and grass offer effective solutions not only in providing dike stability but also in maintaining complete adaptation with the environment.