HOW TO MINIMIZE FLOODING IN CENTRAL LUZON AND THE MARIKINA VALLEY AND METRO MANILA

August 21st, 2013 7 Comments   Posted in Dam water release

HOW TO MINIMIZE FLOODING IN CENTRAL LUZON AND THE MARIKINA VALLEY AND METRO MANILA

The San Roque Dam was designed for a 50-year return flood frequency. Since Typhoon Ondoy and Peping were of the order to a 75-100 year flood, it is thus imperative to lower the dam rule curve by 4-5 meters which is the equivalent of 1 major storm. Please note that it took 6 typhoons to fill up the San Roque Dam to its operating level to provide both power and irrigation during summer. More »

Pre-emptive Discharge of Dam Water – A must even in TVA

December 10th, 2011 No Comments   Posted in Dam water release

TVA opens spill gates of all nine dams in Tennessee River system

(from Dec 8 – McClatchy-Tribune Regional News – Suzanna McCloskey The Knoxville News-Sentinel, Tenn.)

 

 The author of this blog is gratified to know that even the renowed US TVA practices pre-emptive discharge of excess dam water in order to provide sufficent ulage to contain an incoming storm or exceptional rainfall or run-off arising from non-absorptive capability of vegetation during certain periods of the year, thus avoiding the need for catastrophic releases of excess dam water during peak rainfall and run-off. More »

Need to lower the Dam Rule Curve to allow for at least ullage for 1-2 storms

September 29th, 2011 1 Comment   Posted in Dam water release
 
With the series of storms battering the Philippines, it is now necessary to do pre-emptive discharge of excess dam water in order to avoid catastrophic release from dams equipped with spillways, as against the over-flow dams which have no control. More »

Flooding in Brisbane and Australia – need for dam water release simulation model

January 13th, 2011 3 Comments   Posted in environmental impacts

Flooding in Brisbane and Australia – need for dam water release simulation model

It is all over CNN and the cable news.   Brisbane has been hit by an “inland tsunami” arising from dam water release at the height of a typhoon and massive rainfall over the past few days.

It appears that the dam above Brisbane that was designed to protect it from flooding experienced in 1976 released excess water in order to avoid serious damage to the dam structure itself.

This article below will perhaps help the Australian authorities in calculating the needed advanced warning and time for pre-emptive discharge in order to remove excess water at a safe rate so that the incoming storm could be safely contained by the dam. Having sufficient storage capacity of at least one storm (4-6 meters to handle one storm) is a must that should be maintained at all times, especially after a previous storm has exited and an incoming storm has been spotted by the weather bureau through Doppler Radar which locates storms and estimate its rainfall potential. More »