Samanala Wewa Project: Triumphs, Challenges, and the Role of Radioactive Isotopes in Leak Detection

The Samanala Wewa Project, nestled in the picturesque surroundings of Belihuloya, Sri Lanka, where the Walawe River and Belihul Oya converge, represents both an engineering marvel and a lesson in persistence. This report delves into the history, challenges, and recent developments surrounding the Samanala Wewa Project. Additionally, it explores the crucial role of radioactive isotopes in pinpointing the source of a persistent water leak, shedding light on the potential for local scientific advancements in Sri Lanka.

Historical Overview:

The inception of the Samanala Wewa Project dates back to the 1970s during the tenure of Prime Minister Sirimavo Bandaranaike. Initially proposed as a reservoir and power scheme, the project faced skepticism from Russian irrigation engineers, who deemed the site unsuitable for such a construction due to geological concerns. However, in 1986, Japanese irrigation engineers challenged the Russian assessment and commenced the project’s construction. The project entailed a 110m high dam, a 5 1/2 kilometer-long tunnel, and a power plant in the Kapugala area with the potential to generate 120 MW of electricity.

Despite high expectations, the project faced complications, primarily stemming from water leakage issues, leading to significant cost overruns. It was completed in 1992, but the full capacity of the power plant could not be utilized due to the ongoing leakage problem.

The Challenge of Water Leakage:

The water leakage from Samanala Wewa became a persistent issue that defied conventional solutions. Initial attempts to resolve it included constructing a concrete barrier and blocking the mechanical water channel, but the leakage persisted. Even in 1998, efforts to mitigate the issue with a mud layer proved insufficient.

As a result, in 2010, discussions with Indian scholar Dr. K. Sivanana led to the consideration of using atomic isotopes to detect the source of the water leak. Dr. Kamal Laksiri, an engineer, had previously proposed a geological and hydrological method to locate the leak, which was later supported by research from the Atomic Energy Authority.

Radioactive Isotopes in Leak Detection:

The breakthrough came with the use of radioactive isotopes, specifically iodine 131, to pinpoint the location and direction of the water leak in Samanala Wewa. The Atomic Energy Authority, led by Dr. Ranjith Wijewardena, initiated a comprehensive study with a team of researchers. Iodine 131, a synthetically produced isotope with a half-life of 8 days, was introduced into the reservoir at the location identified by Dr. Kamal Laksiri’s mathematical calculations.

The research involved continuous monitoring for 24 hours from six observation points, including holes drilled in the mountain, the tunnel, and the leak location. Water samples were collected and analyzed throughout the process. The study successfully confirmed the accuracy of Dr. Laksiri’s calculations and identified the location of the water leak.

Significance of the Research:

This research not only resolved a long-standing issue with the Samanala Wewa Project but also highlighted the potential for local scientific expertise in Sri Lanka. The ability to utilize radioactive isotopes for complex studies can significantly reduce reliance on foreign experts and save substantial costs.

Future Prospects and Implications:

With the location of the water leak now confirmed, the focus shifts to addressing the issue. Possible solutions include sending divers to the area for further investigation, using underwater cameras, or conducting research during the dry season when the water level in the reservoir is low. The Dam Safety Investigation Team of the Mahaweli Development Authority has expressed its willingness to assist with remediation efforts.

Moreover, the success of this research showcases the capacity of Sri Lanka to conduct advanced scientific studies independently. It serves as an encouraging example of local talent harnessing modern scientific methods for national development projects.

Conclusion:

The Samanala Wewa Project has traversed a tumultuous journey, marked by construction challenges and a persistent water leakage issue. The recent breakthrough in pinpointing the leak’s location through the use of radioactive isotopes is a testament to the potential of local scientific expertise in Sri Lanka. As remediation efforts get underway, the project stands as a symbol of resilience and the ability to overcome complex engineering challenges through innovation and determination.

References:

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