With approximately 87% of Papua New Guinea’s 6.2 million people lacking access to electricity services, a reliable and affordable energy supply is an important sustainable development goal. However, a proposed 180 MW run-of-river hydroelectric power station in the Eastern Highlands presented complex environmental and social challenges, which needed careful consideration for permitting and project design. Golder was engaged to assess the project’s environmental and social impacts, as well as geotechnical conditions.
The Ramu 2 project is downstream of the existing Yonki hydro-electric facilities (Ramu 1). Water will be impounded downstream of Ramu 1 in an intake weir feeding an 8 km underground waterway that transits through the power station. The water will be returned to the Ramu River, approximately 10 km downstream.
To allow communities to make informed judgments about the project, early stakeholder engagement and public participation was crucial. We embedded our team at the project’s location, worked closely with the client, and kept all stakeholders up to date with the project’s progress. This built trust with the local communities.
During our assessment we identified possible changes in the aquatic ecosystem of the Ramu River due to the construction and operation of the weir, intake structure and outfall. Our team implemented thoughtful and appropriate management and mitigation measures, including design changes to facilitate fish passage past the weir, and a long-term water quality management plan for early detection of exceedances of guideline values.
Another risk during this project was the potential that rock extracted from tunnelling and excavation process could form acid if exposed to air and water, thus creating possible negative environmental and social impacts. Therefore, our management plan accounted for ongoing testing and rock characterisation to monitor for the presence of potentially acid-forming material.
The construction of the project would primarily have positive social and economic effects for the local communities, and Papua New Guinea. These included positive impacts to the local economy through creating employment during construction, local business opportunities, and cultural and social cohesion. Community infrastructure would be improved, with greater access to water, sanitation, electricity, health care, and improved transport links.
Building trust with the client and the communities expedited the collection of meaningful data and helped us to deliver a comprehensive environmental and social impact assessment on schedule. Through implementation of Golder’s recommended construction and operational management measures to mitigate impacts, successful completion of the project will lift the electricity generation capacity of the existing Yonki Complex from 93 MW to approximately 270 MW – so that many more Papua New Guineans can enjoy the benefits of clean, reliable and affordable electricity.