The Yatimahana Reservoir Project, situated within the Maha Oya Basin in Mawanella, is a vital infrastructure initiative aimed at enhancing water resources in the region. It is especially critical for augmenting water supplies for domestic, industrial, and agricultural needs in the districts of Kegalle, Kurunegala, Puttalam, and Gampaha. The project also seeks to generate hydropower, contributing to the national grid.

Project Background

The Maha Oya Basin, stretching from the central hill country to the western coastline of Sri Lanka, is a significant source of water for many critical areas, including the Bandaranaike International Airport and several industrial zones. The basin’s increasing demand for water, driven by population growth and industrial expansion, prompted the need for a comprehensive water resource development project.

Project Objectives

The primary objectives of the Yatimahana Reservoir Project are to:

• Improve water availability: The reservoir is designed to meet the increasing demand for potable and industrial water within the Maha Oya Basin.
• Irrigation and hydropower generation: The reservoir will support irrigation activities and contribute to hydropower generation, with an average annual energy output of 26.07 GWh.
• Environmental benefits: The project aims to enhance the water table around the reservoir, benefiting both ecosystems and local communities.

Key Components

The project involves the construction of a main dam and a saddle dam, a powerhouse, and various ancillary structures. Additionally, the project includes off-site components like quarry sites for construction materials and resettlement sites for displaced families.

Environmental and Social Impact

The Environmental Impact Assessment (EIA), conducted by the Mahaweli Consultancy Bureau (MCB), identified both ecological and social impacts. The ecological impacts include the loss of riverine vegetation and habitats due to land clearance and inundation, while social impacts involve the displacement of 248 families and the loss of agricultural lands.

To mitigate these impacts, the project proposes:

• Replanting and creating green habitats around the reservoir.
• Providing adequate compensation and resettlement options for affected families.

Implementing safeguards to reduce ecological damage, such as limiting vegetation clearance and establishing buffer zones.