John Headland, P.E., Principal, Moffatt & Nichol – Sri Lanka COPRI Team Leader

Today, we visited the town of Trincomalee in the northwest region of Sri Lanka. The area is characterized by an expansive estuarial bay (Kaddiyar Bay) which is the terminus of the Mahaweli Ganga, the largest river in Sri Lanka. Although many parts of the bay are protected from ocean waves, portions of these protected areas were significantly damaged by the tsunami. We visited the area on the southern perimeter of the bay, an area that faces east-northeast directly opposite the bay's ocean entrance; specifically, we traveled to the Island of Kinnyai. This island is one of many that have formed at the mouth of the Mahaweli Ganga delta. Access to the island is provided by an ingeniously efficient ferry system comprised of simple barges powered by outboard engines. The island itself was populated by 84,000 residents, of whom 480 perished during the tsunami. The damage was widespread, and included loss of the coastal roadway and many, many buildings, as we had seen elsewhere on previous days. We offered a ride to a local policeman who described the tsunami as a small initial wave followed by a 40-foot wall of black water as high as the palm trees. He also mentioned that houses within 0.5 km of the shoreline were damaged, while the inundation penetrated about 2.5 km.

There were several port facilities in the area, including a cement and a grain terminal. These were located in interior portions of the bay, not directly opposite the bay's ocean entrance. There were no signs of tsunami damage at these sites. Similarly, shore areas on the northern perimeter of the bay within the inner harbor area were relatively unaffected. It seems that the wave was significantly reduced by the shadowing effects of the complicated Kaddiyar Bay geometry.

We left Kinnyai Island late in the day and traveled from Trincomalee to Anuradhapura during an extended period of extraordinary twilight over a very rough road. This road took us through the least-populated areas of our trip. Early along the way, we encountered a series of elephant herds; a special, unexpected treat.

This day ends our technical emprise. We have witnessed the aftermath of immense human suffering. We have vastly extended our understanding of the devastating impacts of tsunami waves. We have observed the tsunami-induced morphological changes to tidal inlets and man-made engineering works (e.g., bridges and causeways). We have gained new knowledge and we have had our basic knowledge dramatically reinforced. We have learned that flooding and resultant loss of life are related to land elevation; that basic education of tsunami wave and flood phenomena will save lives; that flood-zone mapping and the development of vertical or horizontal evacuation routes (either to high ground or away from the shore) will save lives; and that buildings must be properly built. We have learned that wave heights change dramatically from place to place; that the lee side of an island nation can be significantly affected by a tsunami; that tsunamis can penetrate well inland; and that beaches, palm trees, and certain overtopped structures--such as seawalls and other stout wall structures (e.g. Dutch Fort in Galle)--can withstand a tsunami.

It has been an honor for our team to serve COPRI/ASCE in this endeavor, and we applaud its leadership in commissioning our efforts. We also extend our thanks to our new Sri Lankan friends (Suresh deMel, Aro de Mel, Hiran de Mel, Gihan and Ranjit "Galops" Galappatti); our new TCLEE friends (Don Ballantyne, Mary Goodson, Adam Ludwig and Jane Preuss), and ICE member Gordon Masterson. One can imagine that investment in such trips and their subsequent documentation will serve to spread knowledge of natural coastal disasters. It can only be hoped that the lessons learned from such efforts will lead to a better understanding of the important issues that face-and a safer world for those who rely upon-COPRI members.