Hurricane Katrina carries a great impact on the lives of American as well as the view of infrastructure and engineering in the public mindset. If you ask the general public what lead to the demise of New Orleans back in 2005 many will say it was the failed levees that left Louisiana and the 9th District underwater and cost the lives of innocent people who believed they were safe. But why did these levees fail? What could have been done from an engineering standpoint to fix these levees and perhaps save lives, homes, and livelihood.
Even as Louisiana was underwater the U. S. Army core of engineers began to survey the system and damage to determine a plan and study the system failure. Ethically it is an engineers expectation to anticipate potential failures, avoid being negligent, design according to best practices, and continually evaluate the need for corrections. According to the National Science Foundation in a report drafted July 31, 2006 they state that “This event results in the single most costly catastrophic failure of an engineered system in history”.
The report further discusses $200 billion in damages, the deaths of 1500 people, and approximately 450,000 people displaced (Brinkley, 2006). Flood protection and safety measures provided a false sense of safety to the occupants of the City of New Orleans and even the engineers. Failure was sensed most in the design of the levees which left a gap present in the system. This “gap” area allowed water to accumulate and spill over.
According to a journal article published in the National Academy of Engineering in Spring 2007 titled, Engineering for the treat of Natural Disasters and Lessons from Hurricane Katrina they discuss the greatest problem regarding this gap and the greatest downfall that in the 1980’s of a full scale model levee composed of sheetpile/flood-wall system the gap developed and engineering wise the model failed. Water accumulated and flooded at the outboard face of the sheet pile.
Sills et al. goes on to explore these gaps stating, “The formation of gaps behind the floodwalls with hydrostatic pressures acting along the full depth was unforeseen and not ac- counted for in the original designs of the I-wall systems. ” Furthermore, “The stability analysis performed by the IPET 2006 demonstrated that the gap reduced the factor of safety by approximately 25% for clay foundations. The factor of safety in the original design of the 17th Street Canal floodwall in the area of the breach was 1. 30, which was the minimum allowable.
Thus, at the 17th Street Canal breach the combined effect of the knowledge deficiency of the gap formation and a design error caused by the application of centerline strengths to the toe caused the I-wall breach to occur before the design water level was reached” (Sills et al. , 2008). However this failure was never communicated with the field engineers nor did it make the mechanical engineers to reevaluate the design put into practice. The next failure of the mechanical engineers regarding Katrina was the lack to continue to advance design, accept new technology, and stay up to date on current predictions.
The engineers at hand based their “protection system” to protect against a “standard project hurricane” which specifications and baseline were developed in the 1950’s. As time drudged on into the 2000’s the system designed in the 1950’s was no longer “standard hurricane” but instead looked at as a “worse case” design system. Instead of looking at advance in weather predictions, patterns, and using newer science standards the engineers turned a blind eye to advances and development in other fields and never adjusted their scope of work to meet a modern time.
New Orleans is a city surrounded by both the Mississippi River and swampland which is to be noted is below sea level. The flood control structures were authorized and designed relative to a data point water level which reference mean was sea level. However when constructed the data was relative to a geodetic vertical datum incorrectly assumed to be equivalent to sea level. Because of this miscalculation and data points outfall canals and levees were built 1 to 2 feet below the assumed elevation. Water both breached and “gapped” through the failed levees and flood control structures.
This was in relation to design, materials, and failure to test and utilize the results. It is important to recognized that levees had been constructed using… “hydraulic fill and had higher silt and sand content were severely damaged. The levee along the fronts of Lake Borgne was constructed with hydraulic fill that contained significant amounts of sand and silt; it experienced numerous breaches and total loss of the levee section. On the other hand, rolled fill levees that were constructed of cohesive materials, for the most part, were able to survive overtopping without breaching during this event” (Christian,2007).
This starts to allow the mechanical engineer to look at the strength of materials as well as the rational for constructing some levees of superior materials to others. However as administrative panels reviews the “why” for design, materials, and planning choices where no rational was ever discovered. Hurricane Katrina had a great force on engineering and risk management. The Chief of Engineers created a 12 list memorandum for the U. S. Army Core of Engineers after Katrina and one of the greatest items was incorporating “risk based” concepts and testing into design.
This would take into account review, reviews, important of revision with new design and safety at the base. The 12 actions if entirety list concepts that are essential for a prudent mechanical engineer starting at the implementation process stating comprehensively design, construct, maintain and update engineered systems to be more robust, with full stakeholder participation: Employ integrated, comprehensive and systems-based approach; 2. Employ risk-based concepts in planning, design, construction, operations, and major maintenance;
3. Continuously reassess and update policy for program development, planning guidance, design, and construction standards; 4. Employ dynamic independent review; 5. Employ adaptive planning and engineering systems; 6. Focus on sustainability; 7. Review and inspect completed works; and 8. Assess and modify organizational behavior. Then touching on communication, and the importance of being effective and transparent with the public regarding risk and reliability: 9. Effectively communicate risk; and 10. Establish public involvement risk reduction strategies. And Lastly being reliable public service
11. Manage and enhance technical expertise and professionalism; and 12. Invest in research. I list these 12 items because I feel that each one is applicable to an mechanical engineer who has a true Christian worldview and desires to serve the community in the most honest and ethical way possible. The National Society of Professional Engineers Code of Ethics for Engineers placed on emphasis on the importance of professionalism, quality of life, and the impact that we as engineers have on protecting the public, providing safe decisions, that will benefit the general welfare of the people.
The Code of Ethics for Engineers at its heart is much like the Hippocratic oath that a doctors takes to do no harm knowingly; the general public needs engineers to be safe and cognizant of their safety and wellbeing. Therefore it is essential that engineers are truthful and never attempt to deceive those who they work for and provide engineering services for. Had the engineers employed to design, build, and reevaluate the levee and flood system for over a 50 years period in New Orleans been true public servants the devastating effects of Hurricane Katrina could have in theory been avoided.
