How to predict early dam water release – the key to minimizing flooding during typhoons

October 10th, 2009 8 Comments   Posted in large hydro, weather

How to predict early dam water release – the key to minimizing flooding during typhoons

The Philippines is in the news around the world today.  CNN, local media ABS-CBN and other international and local news media reported that five (5) major hydro dams have released water at the onset of Typhoon “Ondoy”, and after a lull, did some pre-emptive release again in anticipation of a new Typhoon “Pepeng”, only to be overwhelmed again with the return of Typhoon “Ondoy” as a result of the “Fujiwara” effect when two adjacent weather disturbances are close to one another.

Unless the dam itself is in danger of collapsing under the weight of its stored water, one could not release dam water at the height of a storm as this will either aggravate existing flooding or initiate wide spread flooding as the rampaging waters will cause land slides and casualties, and destroy earthen dikes, bridges, roads, homes and agricultural lands.

The value of damage and loss of lives could simply not justify the storage of water for future use during summer months for irrigation and power generation.  This necessitates a closer review of the operating “rule curve” of the dam being followed by dam operators in the light of the very recent severe storms bringing large volumes of water over a very short period of time, perhaps as a result of global warming and climate change (warm waters and low pressure areas create extreme weather disturbances characterized with strong winds, heavy rainfall and storm surges that flood coastal areas). More »