Feasibility Study on the Zamboanga City Impounding Dam Project (ZCIDP)

Name of Client:
National Economic and Development Authority (NEDA)


Length of Consultancy Assignment:
Start Date: January 2019
Completion Date: September 2020

Detailed Narrative Description of Project:

The feasibility study (F/S) aimed to determine the viability of the proposed impounding dam project considering the technical, economic, financial, social, environmental, and institutional aspects, among others. Additionally, the F/S will ensure that value engineering/value analysis (VE/VA) is undertaken with regard to the selection of the best possible implementation/project options/configurations for the project to ensure that the best scheme for providing the project’s intended outputs will be selected, which would yield the highest value for money (VfM).

PRIMEX has fielded four specialists to handle various technical aspects of the F/S. The Environmental Engineer is tasked to: (i) conduct an environmental assessment and formulate environmental management plans (EMPs) based on the parameters considered in the pre-F/S and other identified factors; (ii) prepare the Environmental and Social Assessment (ESA) Report of the project consistent with the requirements of the Department of Public Works and Highways (DPWH) and the Zamboanga City Water District (ZCWD), and the prescribed guidelines of the Department of Environment and Natural Resources (DENR); (iii) conduct water quality assessment of the surface water body, with the Hydrologist, to ensure compliance with the Philippine National Standards for Drinking Water; and (iv) provide an initial design for the water treatment plant (WTP), including the layout of process tanks and equipments. The Hydrologist is responsible for: (i) estimating the streamflow at the identified/proposed dams and perform flow duration curves; (ii) estimating the water demand through service water demand analysis and performing systems/basin water balance; (iii) performing hydrologic analysis for various schemes/alternative sites, taking into account a case where hydropower generation is included; (iv) water quality testing and mapping of polluted/sea water-intruded areas; (v) conducting sediment transport analysis for several floodways and each dam site for the determination of sediment-discharge relationship; and (vi) conducting flood studies for different return periods. The Geologist/Geotechnical Specialist is tasked to: (i) conduct the required geotechnical mapping and tests, the specific details on frequency, location, methodology, etc., of the said activities, which shall form part of the Consultant’s Work Plan; (ii) perform slope quantification for the determination and delineation of the various slope class; (iii) conduct surface geological mapping; (iv) perform semi-detailed soil and land classification survey using topographic maps and satellite imagery; (v) validate locations of boreholes indicated in the pre-F/S, and master pits in the potential service area; (vi) conduct/supervise sub-surface geological investigation; (vii) conduct seismic analysis on dam site; and (vii) conduct slope stability analysis on dam site’s abutments. The Hydropower Specialist is assigned to: (i) determine hydroelectric power plant parameters as identified in the pre-F/S; (ii) undertake the design and determination of cost parameters to determine the viability of a hydropower component; (iii) design the required hydraulic turbine/pump, penstock, gate valves, generator, and their control; (iv) identify the location of the turbine/pump, transmission lines, powerhouse, and other components; (v) select the main hydropower characteristics such as installed capacity, energy production, and capacity factor to produce the appropriate power generation scheme for the project; (vi) develop preliminary layouts of hydraulic structures; (viii) prepare the necessary data needed by the Economist and the other experts to carry out indicative assessments of the hydropower component for economic, financial, technical, environmental, and social viability; and (ix) prepare the design, specifications, and cost estimates of the mechanical portion of the dam and other alternatives being considered and their appurtenant structures.