Kandy tremors post-observations: Foreign experts expected in Jan 2021

The State Ministry for Mahaweli Zones, Canals, and Settlement Infrastructure Development is looking to bring down an international team of experts to certify the stability of the Victoria Dam, as well as other major reservoirs in the country.

State Minister Siripala Gamlath (second from left) addressing the media at the Main Dam and Reservoir Operation Centre of the Sri Lanka Mahaweli Authority at Polgolla 

“The team of experts is expected to arrive in January 2021, and would carry out observations, after which they would be able to issue a stability certification that will stand for 30 years,” State Minister for Mahaweli Zones, Canals, and Settlements Infrastructure Development Siripala Gamlath told The Morning.

During a recent site visit to the Main Dam and Reservoir Operation Centre of the Sri Lanka Mahaweli Authority at Polgolla, the State Minister was advised by the engineers in charge of the dam that the stability of the Victoria Dam is 100% affirmed, and that the recent seismic activities reported from the surrounding area had no impact on the dam structure.

Although maintenance of the Victoria Dam has been conducted according to the international standards, a team of experts in the field is to visit and assess the stability of dams in other reservoirs, namely Randenigala, Kothmale, and Senanayake Samudraya.

Mahaweli Zones, Canals, and Settlements Infrastructure Development State Ministry Secretary Wasantha Palugaswewa said the Dam Protection Project has been in place since 1985, while the Dam’s stability has been assessed and fortified at five such instances over the past 35 years.

“The main Dams are maintained under international standards, and all basic reviews with regard to the Victoria Dam under the Dam Protection Programme have been prepared already. The expert team expected in January 2021 will evaluate such reports, and thereafter issue a 30-year guarantee for the stability of the Victoria Dam, if all the observations are in order,” Palugaswewa said.

Sri Lanka Mahaweli Authority Director General Sunil S. Perera said that a discussion was held with the Geological and Civil Engineering Faculty of the University of Peradeniya, which deployed a team of experts for a field visit of the Victoria Dam complex to make recommendations for the future course of action to be taken.

Perera said that the Geological Survey and Mines Bureau (GSMB) is in charge of conducting the necessary monitoring processes, while the duty of the Sri Lanka Mahaweli Authority is to ascertain whether the Dam is affected by earth tremors.

“A 3D movable robot has been installed to check 74 spots of the Dam and issue data daily; accordingly, the safety of the Dam could be assured 100%. Although there are lime deposits in the surrounding areas of the Dam, it has been built on a stable site. The soil samples collected 40 years ago before the Dam was constructed on the site are still available for testing if necessary,” Perera said.

Victoria Dam has been built to resist seismic activities to the magnitude of up to 3.5 on the Richter scale, while none of the recent seismic activities that occurred in the surroundings of Digana has surpassed this maximum limit.

The Victoria Hydropower Project Dam generates 201 MW of power to the national grid, while it also irrigates the farmlands in the Mahaweli B and C Zones. The reservoir has a water capacity of 722 million cubic metres.

Investigations are still underway to confirm whether the tremors are occurring due to lime mining nearby, and some steps will be taken to control lime quarries in Mahaweli lands.