Wailoa Hydropower Project. Fiji

Wailoa Hydropower Project. Fiji

Client: IFC/Hawkins Infrastructure Limited and Fiji Electricity Authority

Industries: Energy

Services: Biodiversity Values and Risk Evaluation, Environmental and Social Impact Assessment (ESIA), Biodiversity Study, Stakeholder Engagement Plan

Background: The aim of the Project was to enhance the supply of reliable electricity to meet expected demand growth in the near future. The Project built on, and was partially integrated with, the recently completed Nadarivatu Hydropower Scheme located downstream from the proposed Project.

The proposed project design involved:

  • Five overflow diversion weirs with drop intake located in the Upper Wailoa catchment and a series of gravity tunnels transporting water from these weirs to the Qaliwana River;
  • A concrete arch dam on the Qaliwana River, upstream from the existing Korolevu Dam and creation of the Qaliwana Reservoir;
  • Intake tower in the Qaliwana Reservoir, including an intake screen and series of control and bulkhead gates;
  • Water conveyance system from the Qaliwana Reservoir to the Qaliwana Powerhouse, consisting of a tunnel and penstock section and a surge shaft;
  • A powerhouse located in the existing Korolevu Weir Reservoir in the vicinity of the Korolevu Weir;
  • An extension of the existing Ba Powerhouse of the Nadarivatu HEP scheme with one additional Pelton turbine and associated equipment;
  • 23 km of associated project roads, and assorted infrastructure elements including quarries;
  • Power reticulation via overhead powerlines to the national grid from the Qaliwana Power House and Ba Power House extension.

Our Role: Argo Environmental was commissioned by IFC/Hawkins to provide consultancy services for the Qaliwana and Upper Wailoa Hydropower Scheme.

Argo was engaged to carry out a biodiversity study of the area to be affected by the proposed hydroelectric power scheme and also to prepare an Environmental and Social Impact Assessment.

In Phase 1, Argo carried out a Biodiversity Values and Risk Assessment Report which was a desktop review of all the available information on the area. The objective was to identify key biodiversity values likely to be present in the study area. Argo also prepared a Stakeholder Engagement Plan which presented and described the stakeholder engagement activities (primarily, information acquisition, disclosure and consultations, and disclosure and dissemination of key issues/results) that were proposed as part of the Environmental and Social Impact Assessment (ESIA) process.

In Phase 2, Argo prepared a Scoping Overview Report which identified matters to be included in the ESIA. The objective of this report was to describe the project elements, define the potential area of influence associated with the project, describe the current known environmental and social status of the Area of Influence, identify key potential social and environmental aspects and impacts and determine which impacts required further investigation during the ESIA phase.

In Phase 3, Argo carried out the field work in Fiji. This involved collecting water quality and macroinvertebrate samples from numerous sites around the affected area to assess the ecological value of freshwater resources. In addition to this, terrestrial surveys of vegetation and birds were organised by Argo. A GIS map was produced, mapping the different vegetation types over the affected area. The Environmental and Social Impact Assessment completed by Argo was done in accordance with the International Finance Commission guidelines as the project was funded by the World Bank.