Tag Archives: flood

Severe Flooding in Thailand

By ThinkReliability Staff

Thailand is experiencing an unusually heavy monsoon season, but it’s management of the rains that are being blamed for the most severe flooding to occur in the area in decades.  Heavy rains resulting from the monsoon season and high tides are creating serious difficulties for officials in the area, who are having to make hard choices with where to divert water and are essentially “sacrificing” certain towns because there’s nowhere else for the water to go.  One of these decisions ended in a gunfight.  Tensions are high, and people are busying themselves attempting to protect their homes and towns with hundreds of thousands of sandbags.

We can examine the issues contributing to the risk to people and property in a Cause Map, or visual root cause analysis.  First, we define the problem within a problem outline.  In the bottom portion of the outline, we capture the impacts to the country’s goals.  More than 200 people have been reported killed as a result of the floods, which are themselves an impact to the environmental goal.  If citizens can be considered customers, the decision to “sacrifice” some towns to save others can be considered an impact to the customer service goal.  The  property goal is impacted by the destruction of towns and the labor goal is impacted by the flood preparations and rescue missions required to protect the population.

Beginning with these goals and asking “Why” questions, we can diagram the cause-and-effect relationships that contribute to the impacts discussed above.  The decision to “sacrifice” some towns to save others is caused by flooding due to heavy monsoon rains and high tides, and the fact that water had to be directed towards some towns, as there is nowhere else for the water to go.  Towns have been built in catchments and areas designed to be reservoirs. Natural waterways have been dammed and diverted.  Dams are full because insufficient water was discharged earlier in the season due to a miscalculation of water levels. Canals have been filled in or are blocked with garbage.  Insufficient control of development in the area has led to insufficient control of water flow, and lack of areas for water to gather – without endangering towns.

Thailand officials are assisting with sandbags and building new flood barriers and drainage canals.  They’re admitting that this issue needs to be repaired.  According to the director of the National Disaster Warning Center, “If we don’t have integrated water management, we will face this problem again next year.”  Hopefully this is the first step in making changes that ensure loss of life and property is minimized during the annual rainy season.

To view the Outline and Cause Map, please click “Download PDF” above.  Or click here to read more


Record Flooding in Minot, ND

By ThinkReliability Staff

Record flooding has struck along the Souris River, leading to record-breaking flooding in Minot and threatening multiple other towns.  The river has widely ranging annual flow rates, varying from 4,200 acre feet to 2.1M acre feet.  Flooding is not uncommon in this part of the country, but what is striking about this case is how events upstream contributed so dramatically to what happened in Minot.

Rivers have always flooded.  Snowmelt and spring rains naturally contribute to higher flow rates.  Rivers also naturally move, as soil erodes in places and builds up in others.  As communities have developed near rivers, a need arose to control the rivers’ boundaries.  After all, you didn’t want to have your farm land constantly submerged by water.  Civilizations have been using earthen structures – like levees or dikes – for thousands of years to control the flow of water.

It was only within the last century, that extensive man-made levees have been built within the U.S.  The levees along the Mississippi River are some of the most elaborate in the world, extending 3,500 miles.  Along with levees, dams help to regulate the flow of water.  Dams can create artificial lakes used either to prevent flooding downstream or to provide a source of water for the community.

How is all of this relevant to the flooding in Minot?  A visual Cause Map can shed light on what led to the intense flooding there.  For starters, the levees meant to keep the Souris River contained were both overtopped and breeched.  This occurred because there was a high volume of water flowing downstream over an extended period of time.  Why is that?

The Souris River actually begins in Saskatchewan, where a further series of levees and dams controls the river.  Southern Canada had a significant amount of snowmelt and spring precipitation, saturating the soil and filling up local lakes and man-made reservoirs.  The area also had a heavy amount of rainfall the preceding the weekend, 4 to 7 inches.   With reservoirs already filled, officials had no choice but to increase dam flow rates to prevent flooding or worse – a burst dam.

While these complex levee and dam systems usually provide stability for riverside communities, they also can work against some of the systems that evolved in nature to keep water flow in check.  For instance, natural levees develop as rivers periodically overflow and deposit silt.  Also everglades and marshlands act like a sponge absorbing excess water.  Human development has affected these natural processes, and unfortunately there are likely to be many further effects from the flooding as the water continues down the Missouri River Basin.