The Official E-Newsletter of the Institution of Engineers Sri Lanka   |  Issue 48 - September / October 2020

Don Gunasena Athukorala - An Icon of Sri Lanka's Civil Engineering History

Interviewed By Samanthika Sarathchandra

This is the story of Don Gunasena Athukorala, an accomplished civil engineer, who contributed immensely to the construction of notable structures in Sri Lanka in the modern era. Don Gunasena was the founding Deputy General Manager and subsequently Chairman of the State Engineering Corporation of Sri Lanka as well as Director, Headworks of the Mahaweli Authority of Sri Lanka. During his career, he provided leadership to many notable public works and heavy engineering projects in the country in a career spanning from the early '60s to the '90s.

Early years

Born in 1924, Don Gunasena gained his primary and secondary education at St. John's College and Sri Sumangala College in Panadura. Although his family wanted him to join the family business, P. D. Pedoris Appuhamy & Company, an import and export concern in Colombo, he preferred to study further. One of his close relatives convinced his father to let him follow his ambition and join the Ceylon Technical College, the premier institution of higher education for technical and engineering studies in Ceylon at the time and part of the Ceylon University College that was affiliated with the University of London.

During the war years, there were only two engineering disciplines on offer, military engineering and civil engineering, and Don Gunasena selected civil engineering. He says, "I wanted to build more permanent structures, while military engineering focussed more on temporary structures such as wooden bridges for troops to cross a river". Those days engineering students got their formal theoretical training in Sri Lanka and practical training in the UK to obtain the Bachelor of Science (Engineering) degree. Upon completion of his studies, he worked for Willment Brothers in Middlesex UK for a year and Scott Wilson Kirkpatrick & Partners in London for about two years. Practical training in the UK entitled him to membership of the Institution of Civil Engineers, the professional engineering body in the United Kingdom.

State Engineering Corporation (SEC)

When he came back to Sri Lanka, he joined the Department of Industries as an engineer. Then in 1962 when the State Engineering Corporation was formed, he joined as Deputy General Manager reporting to A.N.S Kulasinghe, founding Chairman and the General Manager of the SEC, regarded as the father of modern Sri Lankan engineering. Prior to the formation of the SEC, there was no organization that had the capability of chartering large engineering works. Before that most of the projects were carried out by foreign companies. With Kulasinghe's leadership, Athukorala was able to develop the SEC to a fully functional engineering organization with the capability of handling large construction projects.

SEC and Diversion of the Mahaweli River

Polgolla Dam and Tunnel: One of the projects that was handled by the SEC in the 1970s was the construction of the Polgolla Dam, the first of many large projects under the Mahaweli River diversion scheme. The dam diverted the Mahaweli river at Polgolla. The project was planned locally by the Mahaweli Development Board and the construction was handled by the SEC.

Planning and construction of the Polgolla tunnel was not an easy task. Athukorala and SEC leaders were facing many problems during the construction. The tunnel was a horseshoe-shaped underground tunnel and was 8 kilo meters long. It conveyed 2000 cusecs of water from the Polgolla reservoir to the Ukuwela hydropower station.

The excavation method of the tunnel was the drill and blast method passing through different rock layers consisting ofGarnet sillimanite biotite gneiss, Charnockitic gneiss, Biotite hornblende gneiss (about 60 per cent), and Granitic gneiss. In the longitude profile of the tunnel, there were three deep shears or fault zones. The shear zone three runs along the axial plane of a synform and above the tunnel trace, small rift runs along a ridge. At 7,800m length of the tunnel, first water leakage was identified and this was the starting point of many problems. The water brought a large volume of sand, silt, and rock debris into the tunnel. This caused delaying of in the considered area. Drainage holes were constructed in this area, and reinforcement concrete was laid for 27% length of the tunnel.

The Polgolla construction was fully handled by Sri Lankan local engineers and was a very challenging task. Don Gunasena was directly involved with the Polgolla project and provided leadership with his structural engineering skills and experience.

Former director of Mahaweli Headworks Engineer S. Karunaratne says "Planning of the Phase 1 task was not easy, as there were several drawbacks during construction. Polgolla tunnel leakage, flood damages during the construction of Polgolla barrage, Ukuwela Powerhouse base construction issues were looked at as critical items, and planning was revised accordingly. Don Gunasena's structural engineering knowledge greatly contributed to resolve the construction issues."

Kotmale Dam and Tunnel: The Kotmale hydropower tunnel had similar issues. The tunnel passed through slightly weathered and very strong rock, but the intake area and a small section of the tunnel had weak rock. The major rocks that were encountered were Garnet sillimanite biotite gneiss, Charnockitic biotite gneiss, and Quartzite. The major geological challenges were folding, fracturing, and foliation shear zones. Before the construction, a thorough study was conducted for the soil structure and found prominent fracture systems in the catchment area. They were mainly, foliation joints and shear zones parallel to lineaments. The tunnel passed through two lineaments, Ela fault and Ganga lineament, which appear as narrow shear zones. Major foliation shears with the slicken sided surface were present for a considerable length of the tunnel. In the excavation process, there were a few problems that had been identified. However, when the tunnel passed through the weathered rocks, the water engrossed to the tunnel. To solve this problem, steal arc supports were used in the area of crossing the lineament. Other weak zones were treated by shotcrete to consolidate the rock, steal ribs, cavities filled with concrete, rock bolts, and control blasting. Enormous soil and structural engineering knowledge was needed to accomplish this project.

Athukorala and his colleagues possessed this knowledge to complete the project successfully. The SEC was a major contributor to the construction of Mahaweli reservoirs and dams under the leadership of Athukorala.

There were several other notable projects that were undertaken and delivered by the SEC during Athukorala's tenure.

The Kalutara Bodhi Chaitya

Built in the late 1960s, the Kalutara Bodhi Chaitya, Sri Lanka's first thin shell hemispherical stupa, is another noteworthy construction designed by Kulasinghe and carried out with the direct supervision of Don Gunasena.. The large 30.5 m (100 ft) diameter and 91.5 m (300 ft) circumference concrete dome has a thin shell with a thickness of 140 mm (5.5 in). In the 1970s, the SEC owned the country's first mainframe computer and used it to do the complex calculation for the planning stage of the Kalutara Bodhi Chaitya .

The Colombo Planetarium

Don Gunasena was also directly involved in the design of the Colombo Planetarium built as a special feature for the Ceylon Industrial Exhibition in 1965. The building has a reinforced concrete floor and a pre-stressed concrete folded plate roof, which was pre-cast on site.

Engineer Shantha Jayasundara, Consultant to the World Bank and the Asian Development Bank and a former Deputy Municipal Commissioner says "At the time the Colombo Planetarium was built Don Gunasena was at the SEC. There were five pioneering engineers. They were Dr. Kulasinghe, Don Gunasena who was the Deputy General Manager, Titus Gunasekara, Basil Chitty and Nevile Ladduwahetti. They were the people who teamed up to form the State Engineering Corporation".

Shantha Jayasundera also said "at that time huge cranes and structural engineering were not known. The scale of the engineering was very low. With the formation of the State Engineering Corporation, they were able to get long-barrier cranes and technologies like steam curing, pre-tensioning and posts tensioning. The idea was to produce more within a short time as time was running out and they needed to catch up. The planetarium was the one of project that was done at that time. The purpose was to give an understanding to children about the universe and to showcase our local engineering skills during the Ceylon Industrial Exhibition. They had good architectural design and SEC undertook to do that. It was challenging design at that time for civil engineering."

Other projects

There were many projects undertaken by the SEC with the leadership and guidance of Athukorala. Examples are the construction of Lanka Leyland Corporation, Ceylon Steel Corporation, Thulhiriya milling corporation, etc.

The SEC also built overhead pedestrian bridges to reduce the congestion on the roads in Colombo.

Mahaweli Authority

In 1980, Don Gunasena joined the Mahaweli Authority of Sri Lanka in the newly formed Headworks Division as the director and was responsible for the formulation of the work at the headworks division.

Engineer Karunaratne says "In 1985, the Mahaweli Authority of Sri Lanka appointed Don Gunasena as the founding Director of the Headworks Division. I was selected as the Deputy Director of the Division to perform the tasks of the Division, under his directions. The main function of the division was to understudy the completed projects under the Mahaweli Development Program, and take over for Administration, Operation, and Maintenance work. This was not an easy task."

Before that the primary responsibility of the maintenance division was to transmit the daily water levels to the head office and manage/maintain the Irrigation tunnel gates according to the weekly water requirements. Once a week the requirements arrived from the Water Management Division of Mahaweli Authority. Don Gunasena identified and managed the requirements and prepared detailed reports to Director General of Mahaweli Authority, about the situation and actions to be taken. It took several months to arrange offices, attending to clearing works and a schedule of maintenance programs was prepared. Funding requirements were also arranged with additional staff for technical and finance activities. Proper communication facilities were established so that the Director can link directly to the site staff.

Dam Instrumentation: There were several maintenance manuals and processes written for Dam maintenance. Dams such as Victoria were built with the latest technology at that time and there were various types of movements, pressures, stresses, and strains to check and maintain. He thoroughly studied the behavior of instruments and their functional nature. He and his Deputy Director S. Karunarathna jointly prepared a 'Dam Instrumentation' paper and presented it at the Annual Sessions of the Institution of Engineers in 1989.

Don Gunasena was keen on studying the environmental issues of the newly formed reservoirs, such as the 'salvinia' weed spread over the Maduru Oya Reservoir, blue-green algae formation in Kothmale Reservoir and formation of massive 'nidikumba' (Mimosa pigra) in the upper area of Victoria Reservoir periphery. Athukorala was a very scientific person and the solutions he has given for these environmental problems were very sustainable.

Retired life

In 1995 Don Gunasena retired from the Mahaweli Authority. In January 1999, he and his wife, Irangani, migrated to Sydney, Australia, and have lived there since. They have three children and six grandchildren living in Australia and the UK.

In the early years of his retirement in Sydney, he was involved in the University of the Third Age (U3A). It is an international education and development program for people in retirement. He studied short computer courses to keep his mind engaged and also helped a students in the local area with computer-aided design.

He also pursued his interests in the science of Buddhist teachings. In 2012 he authored a book relating to his understanding and interpretation of Paticcasamuppada. The book is titled "Buddha's Principle of Relativity" and is based on the philosophy of dependent arising. As Don Gunasena sees it, Abhidhamma is science. Paticcasamuppada is Buddha's explanation of how the human body works - it is a biological process. The book is available on Amazon.


Interviewed By Samanthika Sarathchandra
E- mail -
Phone number - 0772353885