For Conducting Feasibility Study of Dhoingakata Natural Reservoir as a Drinking Water Source in Ukhiya, Cox’s Bazar, Bangladesh.

TERMS OF REFERENCE FOR INSTITUTIONAL CONTRACT

Title of the assignment

Conducting Feasibility Study of Dhoingakata Natural Reservoir as a Drinking Water Source in Ukhiya, Cox’s Bazar.

Purpose

The purpose of this Terms of Reference (TOR) is to engage a qualified consulting firm to undertake a comprehensive techno-feasibility study and Environmental and Social Impact Assessment (ESIA) for the development of the Dhoingakata Natural Reservoir as a sustainable and climate-resilient drinking water source in Ukhiya, Cox’s Bazar. The study will assess technical, hydrological, environmental, ecological, social, financial, and institutional viability to support the provision of safe and sustainable drinking water for both host communities and Forcibly Displaced Myanmar Nationals (FDMNs). The assignment will further inform infrastructure planning, environmental compliance, ecological conservation, risk mitigation, and long-term sustainable water resource management in the region.

This TOR requires a comprehensive evaluation of the reservoir as a long-term raw water source, including sustainable water abstraction, treatment, transmission, storage, and distribution systems, while ensuring environmental protection, ecological conservation, and adherence to social safeguards.

Location

Dhaka and Ukhiya, Cox’s Bazar

Estimated Duration

Duration: 8 months

Reporting to Technical Supervisor of this assignment

WASH Specialist

1. Background

Cox’s Bazar is facing increasing challenges in ensuring access to sustainable, safe, and climate-resilient drinking water supply for both host communities and Forcibly Displaced Myanmar Nationals (FDMNs). Rapid population growth, prolonged humanitarian pressures, groundwater overextraction, salinity intrusion, deforestation, and climate variability have placed significant stress on existing water resources and WASH infrastructure. In Ukhiya and Teknaf, a heavy reliance on shallow aquifers has resulted in groundwater depletion, with many sources becoming non-functional during extended dry periods.

In response, the Department of Public Health Engineering (DPHE) has identified the Dhoingakata Natural Reservoir in Ukhiya/Teknaf as a potential alternative surface water source. The reservoir is naturally recharged through runoff from surrounding hill catchments and presents an opportunity to transition towards renewable surface water use. Preliminary assessments conducted under the ADB-funded Emergency Assistance Project (EAP) indicate that, with appropriate infrastructure, environmental safeguards, and climate-resilient management approaches, the reservoir could provide a sustainable drinking water source for Rohingya refugees and host communities in Whykong, Unchiprang, and surrounding areas.

The reservoir provides important ecological and socio-economic functions. Its overflow supports local livelihoods, including agriculture and small-scale economic activities, while the surroundings serve as habitat and water access for wildlife such as elephants and deer. Any development for drinking water supply must therefore balance water abstraction with ecological conservation, existing community uses, and environmental sustainability considerations.

Recognizing the urgency need for sustainable alternative water sources in the water-scarce areas of Cox’s Bazar, DPHE formally requested UNICEF’s technical support for environmental and social assessments and surface water supply development, leveraging UNICEF’s expertise in WASH, safeguards, climate-resilient infrastructure, and multi-stakeholder coordination.

In response, UNICEF, under the GoB–UNICEF Climate Resilient WASH Project, will support a comprehensive techno-feasibility and Environmental and Social Impact Assessment (ESIA) of the Dhoingakata Reservoir. The study will evaluate its technical, hydrological, environmental, ecological, social, financial, and institutional viability as a sustainable, climate-resilient water source for vulnerable host and refugee populations in Cox’s Bazar.

2. Objectives, Purpose and Expected Results

The objective of this assignment is to conduct a comprehensive techno-feasibility study and Environmental and Social Impact Assessment (ESIA) of the Dhoingakata Natural Reservoir to determine its viability as a sustainable, climate-resilient, and safe drinking water source for host communities and Forcibly Displaced Myanmar Nationals (FDMNs) in Ukhiya, Cox’s Bazar.

The assignment aims to generate evidence-based technical, environmental, ecological, social, financial, and institutional analyses to support informed decision-making for future surface water investments in water-scarce areas of Cox’s Bazar. The study will assess reservoir hydrology, water quality, climate resilience, ecological sensitivity, infrastructure options, and safeguard requirements, ensuring compliance with national regulations and environmental standards. It will also support the preparation of implementation strategies, environmental clearance processes, and long-term sustainable water resource management.

The assignment is expected to achieve the following results:

A comprehensive feasibility and ESIA study for the Dhoingakata Reservoir, based on a design horizon of at least 20 years

Population projections and water demand analysis were completed.

Reliable technical and hydrological data generated, including High-Resolution Digital Elevation Model (DEM), bathymetric survey, climate analysis, and seasonal water availability;

Technically feasible and climate-resilient options identified for water abstraction, treatment, storage, and distribution;

Capital and operation & maintenance (O&M) costs estimated, with financial sustainability and cost-recovery mechanisms

Institutional and regulatory frameworks reviewed, with recommendations for improved governance and compliance.

Environmental, ecological, and social risks are assessed, with mitigation measures, including conservation and wildlife protection.

Preliminary engineering concepts and cost estimates developed for future investment planning;

Compliance with Department of Environment (DoE) and Bangladesh Forest Department (BFD) requirements supported, including facilitation of statutory clearances; and

Statutory clearances from the DoE and DoF secured for Dhoingakata Natural Reservoir construction as a Drinking Water Source

Evidence-based recommendations provided to strengthen long-term water security and sustainable WASH service

3. Description of Assignment

The assignment will support the DPHE and UNICEF Bangladesh in conducting a comprehensive techno-feasibility and Environmental and Social Impact Assessment (ESIA) of the Dhoingakata Natural Reservoir as a climate-resilient surface water source for host communities and FDMNs. The study will generate the technical, environmental, ecological, social, financial, and institutional evidence required to guide future planning, investment, and implementation of sustainable water supply systems in water-scarce areas of Cox’s Bazar.

3.1 Hydrological, Climate and Water Availability Assessment

Review existing hydrological studies, climatic records, reservoir data, and relevant policies and regulatory documents.

Analyze rainfall, evapotranspiration, seasonal variation, reservoir dynamics, and climate variability to assess long-term water availability.

Conduct water balance and safe yield analysis, supported by hydrological modelling under normal, dry, and extreme climatic conditions.

Develop seasonal water availability scenarios and assess climate resilience of the proposed water supply system.

3.2 Topographic, Bathymetric Survey and DEM Development

Conduct drone-based, topographic, and bathymetric surveys of the reservoir and surrounding areas.

Develop a high-resolution Digital Elevation Model (DEM) by integrating survey datasets.

Perform catchment delineation, drainage analysis, inundation mapping, and reservoir storage assessment.

Prepare water depth, seasonal