The Uma Oya Multipurpose Development Project is a landmark initiative spearheaded by the Irrigation Ministry, designed to optimize the use of water resources in Sri Lanka’s Uva and Southern provinces. With a focus on addressing multiple critical needs—agriculture, water supply, and energy generation—the project is poised to play a pivotal role in the socio-economic development of the region.

Project Background and Objectives

The Uma Oya River, a key tributary of the Mahaweli River, is central to this project. The primary objective is to utilize the river’s water to meet three critical demands:

1. Irrigation: The project aims to enhance agricultural productivity by providing reliable irrigation to approximately 6,000 hectares of farmland. This includes 4,500 hectares of new agricultural lands in the Moneragala District and the support of 1,500 hectares of existing land. By improving water availability, the project seeks to boost agricultural output, thereby enhancing food security and the livelihoods of farmers in the region.
2. Hydropower Generation: The project is set to generate 120 MW of electricity, contributing approximately 231 GWh annually to the national grid. This addition is significant for Sri Lanka’s energy sector, which is heavily reliant on hydropower. The electricity generated will not only support local communities but also strengthen the national energy supply, reducing dependency on fossil fuels and contributing to a greener, more sustainable energy mix.
3. Water Supply for Domestic and Industrial Use: The project includes provisions to deliver 30 million cubic meters (MCM) of water annually for drinking and industrial use, particularly in the Hambantota and Moneragala districts. This will address the chronic water shortages in these arid regions, improving living conditions and supporting industrial activities that are vital for economic growth.

Infrastructure and Technical Components

The Uma Oya Multipurpose Development Project involves several complex engineering works:

• Headworks and Tunnels: The core of the project includes the construction of two main reservoirs, the Puhulpola and Dyraaba reservoirs. These reservoirs are interconnected through a series of tunnels that divert water from the Uma Oya Basin towards the Kirindi Oya Basin. The headworks involve an elaborate tunnel system with a total length of approximately 25 kilometers, which includes a 3.9 km tunnel from the Puhulpola Reservoir to the Dyraaba Reservoir and a 15.5 km headrace tunnel from Dyraaba to the underground power station.
• Underground Power Station: The project features an underground powerhouse located near the city of Wellawaya. The design includes two turbines, each with a capacity of 60 MW, ensuring efficient energy generation. The power station is strategically positioned to minimize environmental impact and to harness the full potential of the diverted water.
• Downstream Development: After electricity generation, the water is released into the Alikotaara Reservoir, from where it is distributed to the agricultural lands of Moneragala and Hambantota. The downstream development component also includes the construction of canals and irrigation systems to ensure efficient water distribution to the farmlands.

Environmental and Social Considerations

Recognizing the potential environmental and social impacts of such a large-scale project, comprehensive studies were conducted to ensure that the project is sustainable and minimizes adverse effects:

• Environmental Impact Assessments (EIA): The EIA process was a critical part of the project, ensuring that all potential environmental risks were identified and mitigated. This included the assessment of impacts on biodiversity, water quality, and the displacement of local communities.
• Resettlement and Livelihood Restoration: The project has necessitated the resettlement of several communities. To address this, the Irrigation Ministry, along with local authorities, has implemented resettlement plans that provide affected families with new homes, compensation, and support for livelihood restoration. The goal is to ensure that the displaced communities benefit from the project through improved living conditions and access to new opportunities.
• Water Management and Conservation: The project incorporates modern water management techniques to optimize the use of available water resources. This includes the construction of check dams, water harvesting systems, and the promotion of efficient irrigation methods to reduce water waste.

Economic and Social Benefits

The Uma Oya project is expected to have far-reaching economic and social benefits:

• Boost to Agriculture: With improved irrigation, farmers in the region can expect higher crop yields, which will increase their income and reduce poverty levels. The project is also expected to support the cultivation of high-value crops, which will contribute to the diversification and commercialization of agriculture in the region.
• Enhanced Energy Security: By adding 120 MW of clean, renewable energy to the national grid, the project will help meet the growing energy demand in Sri Lanka, reduce energy costs, and enhance the country’s energy security.
• Improved Water Supply: The provision of 30 MCM of water for domestic and industrial use will improve the quality of life for residents in the Hambantota and Moneragala districts, who have historically faced water shortages. This, in turn, will attract investment to these regions, fostering industrial growth and job creation.
• Job Creation and Economic Growth: During the construction phase, the project has provided thousands of jobs to local residents, boosting the local economy. In the long term, the increased availability of water and energy will support the growth of industries, tourism, and other economic activities in the region.

1. MCB played a crucial role in the project by providing essential consultancy services, particularly in the areas of environmental management and compliance. MCB’s contributions included conducting the Initial Environmental Examination (IEE), which was vital for assessing the environmental impact of the project. This assessment ensured that the project adhered to both local and international environmental standards, minimizing the ecological footprint and addressing potential social impacts such as the displacement of communities.