Consulting Firm for Flood Modeling and Flood Hazard Assessment for selected districts in selected River Basins in Bangladesh, Nepal and Pakistan

Countries: Bangladesh, Nepal, Pakistan

Organization: Asian Disaster Preparedness Center

Closing date: 6 Jan 2022

Section I: Introduction and Background

A. About Asian Disaster Preparedness Center (ADPC)

ADPC is an autonomous international organization with a vision to reduce disaster and climate risk impacts on communities and countries in Asia and the Pacific by working with governments, development partners, international organizations, NGOs, civil society, private sector, media, and other key stakeholders. Established in 1986 as a technical capacity building center, ADPC has grown and diversified its expertise across social and physical sciences to support sustainable solutions for risk reduction across a broad range of specialist areas. With over 100 staff from 19 different nationalities and a wide range of professional expertise from atmospheric scientists to social scientists with experiences from all levels of engagement typically required for Disaster Risk Reduction (DRR) and Climate Resilience (CR) in an effective manner. ADPC is a competent regional resource center and has seven thematic departments: ADPC Academy, Risk Governance, Climate Resilience, Urban Resilience, Health Risk Management, Preparedness for Response and Recovery, Geospatial Information. These are supported by Finance, Human Resources and Administration, and Strategic Planning departments. In addition to the departments, ADPC works on three cross-cutting themes: Gender and Diversity, Poverty and Livelihoods, and Regional and Transboundary Cooperation through permanent working committees.

For details, please refer to ADPC website at http://www.adpc.net/.

B. About Climate Adaptation and Resilience for South Asia project

The "Climate Adaptation and Resilience for South Asia" or CARE for South Asia project is a five-year (2020-2025), regional project supported by the World Bank, and implemented by Asia Disaster Preparedness Center (ADPC) and Regional Integrated Multi-Hazard Early Warning System for Africa and Asia (RIMES). The project is supporting the region in building resilience to climate change by improving the availability of regional data and knowledge, developing guidelines, tools and capacities, and promoting climate-resilient decisions, policies and investments across key sectors. The development objective is to contribute to an enabling environment for climate resilience policies and investments in select sectors and countries in South Asia. Key stakeholders include governments and technical agencies at the regional and national level. With the financial support from the World Bank Group, ADPC will be implementing a five years’ project, titled “Climate Adaptation and Resilience Project for South Asia” (CARE).

C. Background:

Agriculture is the main source of livelihood in South Asia. The majority of the economically active population is reliant on agriculture for their livelihoods (CGIAR). The agriculture sector contributes approximately 19% of the regional Gross Domestic Product (World Bank). However, Agriculture in South Asia is highly susceptible to climate variability and climate change, given their sensitivity to variations in temperature, precipitation, and the occurrence of extreme events and disasters such as droughts, floods, and cyclones. Several locational factors such as distinct geography, demographic trends, socio-economic factors, traditional farming practices, and limited adaptive capacities also increase the vulnerability of countries in South Asia (CGIAR). Similarly, road transport is key to enabling many aspects of economic life such as trade, public services delivery, governance, tourism, and other economic activities in South Asia. Governments invest significantly in road infrastructure to provide connectivity to all economic zones primarily to reduce poverty and promote rural development. This requires more concerted efforts towards improving the current road infrastructure, especially in the geologically fragile mountain terrain of Nepal and in the flat terrain of Bangladesh, which is highly vulnerable to climate change impacts such as floods, storm surges and landslides caused by heavy rain and cyclones.

According to the Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (AR5) summary for the South Asia region, warming trends including increasing annual mean temperature at the country scale have been observed across most of the countries in South Asia (IPCC, 2014). In South Asia, seasonal mean rainfall shows a declining trend with more frequent deficit monsoon, more frequent heavy precipitation events, and decreasing light rain events, which is highly useful for agriculture (IPCC, 2014). These extreme climate events will have an increasing impact on agriculture, human health, security, livelihoods, and poverty, with the type and magnitude of impact varying across South Asia. The impacts of climate change on food production and food security in South Asia will vary, with many countries experiencing a decline in trends in productivity (IPCC, 2014).

Agriculture-dependent countries in South Asia such as Bangladesh, Nepal and Pakistan are highly vulnerable to climate change and associated hazards such as floods. Floods are most common and recurrent hydro-meteorological hazards in Bangladesh, Nepal and Pakistan. Every year floods claim thousands of lives in addition to leaving millions homeless and inflicting considerable loss to agriculture, livestock, property and infrastructure. Floods can be of several types such as riverine or fluvial, estuarine, coastal, catastrophic, flash, hill torrential or, the recent trend: skewed urban or pluvial floods.

In realizing the need to understand the impact of flood hazard on agriculture as well as on transport sector, the services of a consultant will be required to conduct flood (hydrological and hydrodynamic) modeling and flood hazard assessment for selected province/districts in selected River Basins in Bangladesh, Nepal and Pakistan under CARE for South Asia project.

Section II. Objective and Scope of the Services:

A. Objective:

The main objective of the consultancy services is to conduct flood (hydrological and hydrodynamic) and flash flood modeling and flood hazard assessment for selected provinces/districts in selected River Basins in Bangladesh, Nepal and Pakistan. The focus of this study will be on fluvial flooding and should use a hydrologic and hydrodynamic modeling approach to generate1D, 2D and combined flood simulation model results for fluvial flood hazard assessment. The details of selected province/districts in Bangladesh, Nepal and Pakistan is provided in following table.

Flood Type

Province/District Name

Bangladesh

River Floods

Kurigram

Gaibandha

Jamalpur

Pabna

Sirajganj

Flash Floods

Sunamganj

Kishoreganj

Coastal Floods/ Storm Surge

Barguna

Patuakhali

Bhola

Satkhira

Cox’s Bazar

Nepal

River Flood including Flash Floods

Province 2 & Bagmati Province

Pakistan

River Floods

Punjab Province

B. Scope of Work:

The scope of work is as follows:

Detailed consultations with the Project Implementation Unit (PIU), Agriculture and Transport Sector teams of CARE for South Asia Project in Bangladesh, Nepal and Pakistan to understand all the key activities, data requirements, deliverables and timeline.
Presentation of the methodology, work plan, deliverables and timeline to the PIU, Agriculture and transport Sector team CARE for South Asia Project in Bangladesh Nepal and Pakistan.
Presentation of detail methodology and workplan with concerned government authorities at federal and provincial levels.
Organize validation workshops with federal and provincial governments to validate the findings and receive endorsement from the government.

Data:

Assessment of data needs for the study of hydrological and hydrodynamic modeling, flood hazard assessment, and mapping.
Collection of data relevant for flood and flash flood modeling and flood hazard assessment in Bangladesh, Nepal and Pakistan.
Collection of hydrological, meteorological and other data from existing sources. The data may include river cross-section data collected during recent studies (within last 5 years) from relevant agencies in the project countries.
Develop inventory of data available for flood hazard assessment and mapping, in particular the data needed for hydrological and hydrodynamic model development.
Analysis of data gaps, including data quantity and quality related to requirements for the completion of hydrological and hydrodynamic models for studying riverine or fluvial flood hazards assessment.
Based on the data gaps identified, collection of all relevant data for the study, such as time series: rainfall data, river water levels and discharges, hydrographs for relevant rivers, historic flood information etc.
Collection of spatial information including river bathymetry, river cross sections, watersheds, hydraulic structure data, digital surface and terrain level data, etc. Furthermore, the collection of spatial information would include development/acquisition of GIS layers serving the needs of hydrological modelling, such as layers providing information on terrain slopes, soil type and thickness, land cover, vegetation, etc., and for the presentation of model and other study results.
Include roads, bridges, retaining and other major road structures within 300-500m (or within appropriate extent depending on river morphology but not exceeding 500m) from the high flood levels (HFL) of the selected rivers in Bangladesh and Nepal in the cross-section measurements. Planned cross-section measurements shall be extended beyond the HFL (max. of 500m) to include the road infrastructures where they exist. Cross-section shall be collected at the c/l of bridge with additional 2 to 4 cross-sections upstream and downstream at appropriate intervals required for hydraulic modelling.
Appropriate considerations of roads, bridges, retaining and other major road structures within the HFL of the rivers and flood plain of Coastal Flood/Storm Surge shall be done for hydraulic analysis required for flood inundation modelling.
In case of availability of recent river cross section data, DEM and other data, these shall be acquired from reliable authorities. Assessment of these secondary data shall be done for accuracy and usability for the assignment.
In case of DEM, available data of most appropriate resolution shall be used. Comparative assessment shall be done for different available DEM (national DEM, SRTM/MERIT, ASTER GDEM, ALOS PALSAR DEM, CARTOSAT-1 DEM) and the most appropriate shall be used for the flood modelling.
The new development plans for road and bridge need to be considered alongside the existing condition in discussion with relevant authorities (bridges of more than 100.0m length with foundation obstructing river flows).
Collection of land use data to analyze potential impacts of floods in arable land (river cutting, sand deposition, siltation, crop and livestock damage) and identify adaptive land use and agricultural practices in the medium and long-run.
Collection of historical data on inundation of crop lands and scenario analysis to identify potentially inundation-prone area to identify highly vulnerable geographic locations and agricultural systems (hotspots).
Preparation of a base map for the selected river basins, serving as a background for hydrological and hydrodynamic model development to present model results and for the generation of flood hazard maps.

Model:

Develop hydrological and hydrodynamic models for selected river basins in Bangladesh, Nepal and Pakistan based on data availability, calibration, adequate simulation of flood volumes and peak flows as well as reliable simulation of dominant hydrological processes.
Calibration of the hydrological and hydrodynamic models and the channel and overland flow roughness parameters on the basis of past floods and the sensitivity analysis of peak flows. Hydrological and hydraulic models must be calibrated to previously recorded flood events. While calibrating, the period of the event in relation to the vegetation and morphological changes should be taken into the account. Before the calibration the historical/recorded data should be critically evaluated and excluded in case of inconsistencies.
Validation of the hydrological and hydrodynamic models using at least one flood event different from the ones used for calibration.
Carry out a sensitivity analysis of hydrological and hydrodynamic parameters (e.g. spatial and temporal variation, rainfall losses, lag, catchment storage, roughness, energy losses, bridge coefficients, boundary conditions etc.) and discuss uncertainty sources and further steps for a probabilistic analysis.

Maps and Reports:

Produce estimated potential flood hazard maps for 1 in 10, 20, 50, 100 and 500-year return periods on the basis of model simulations with the different climate change scenarios (RCP 4.5 and RCP 8.5) in 2030, 2050s and 2080s.
Flood hazard maps of above return periods should be generated as GIS layers to include the following:
- Flood outlines showing the flood extent,
- Flood depth at each model element.
- Flood velocities and time durations of flood water extent.
Determine flood warning and danger levels at selected flood forecasting station locations for early warning systems.

Section III. Deliverables

The consulting firm will be required to submit the following deliverables as a result of the implementation of activities as outlined in these terms of reference:

Initial scoping report elaborating on the methodologies for key activities, tools and workplans for the consultancy (30 days after signing contract).
Potential flood hazard maps and GIS datasets (flood extents, depths, velocities in appropriate GIS format and resolutions) for 1 in 10, 20, 50, 100 and 500-year return periods on the basis of model simulations with the different climate change scenarios (RCP 4.5 and RCP 8.5) in 2030, 2050s and 2080s for selected river basins in Bangladesh, Nepal and Pakistan (6 months after signing contract).
Detailed flood hazard assessment report with analysis and findings for selected river basins in Bangladesh, Nepal and Pakistan for both road transport and agriculture sectors (8 months after signing contract).
The flood hazard assessment report should contain justification of the modelling method, modelling software used, limitations of the modelling method and of the software used as well as a detailed description of the procedure, any assumption made for model simplification and data used analysis of hydraulic structures and their impact on water levels. It should also include information on uncertainties as well as any other issues which may affect the accuracy of output.
Detailed final closure report covering the results and achievements including knowledge products prepared, analysis, findings, lessons learnt, and conclusion and recommendations (9 months after signing contract – to be discussed at contract negotiation)**.**
Monthly report on the progress of activities and monitoring of deliverables ( end of every calendar month).

Section IV. Selection, and Others:

A. Selection Criteria:

The Consultant is expected to be a firm or an association of consulting firms with the appropriate capabilities and experience of at least 7 years with specific capacity to execute the services in riverine and flash flood hazard assessment, hydrology and hydrodynamic modeling, flood modeling and simulation, weather and climate modelling in South Asia in the last 5 years.
This assignment requires a team of international, regional, and national experts/consultants to ensure the integration of international and national best practices and standards into the study.
The Consultant team may propose additional technical experts to improve the quality of the output.
The Consultant should have a track record in carrying out technical assistance and consultancy services on flood hazard assessment, hydrology, water resource management, and project management, and have proven experience in planning, implementation and management of programs related to flood hazard assessment, stakeholder engagement aspects.
The Consultant should have proven experience of working with federal and provincial government agencies, the World Bank, Asian Development Bank, UN or international agencies in South Asia.
The Consultant should have proven experience of undertaking assignment of similar nature in South Asia.
The Consultant should have good understanding of water resource management sector and climate change issues in South Asia.
The Consultant should have proven ability for data collection, and analysis for relevant activities.
The Consultant should have availability and access to Infrastructure/equipment/software etc. required for the completion of the assignment.
The Consultant should demonstrate financial capacity to execute this requirement.
The Consultant should demonstrate financial capacity based on previous activities which align to the current requirements.
The Consultant should evidence financial size of the last three (3) projects and year wise turnover for the last five (5) financial years.
The Consultant should have the following essential technical expertise/human resources to complete activities and tasks and deliver quality outputs on time. However, these are indicative and the firms are encouraged to propose additional inputs required to complete the assignment within the schedule.

Key Position

Senior Flood Hazard Assessment Specialist - Team Leader

(International/Regional)

M.Sc./M.Tech. in Hydrology, Water Resource, Civil Engineering with 20 years of relevant experience in integrated urban flood risk management, river basin management, hydraulic engineering, flood modelling, operation and maintenance of urban flood control and drainage systems, hydrology, water resources management, civil engineering and disaster risk management institutional issues. The Team Leader should have project management capability, including managing teams of national / international experts. He/she should have excellent communication skills, presentation skills and ability to prepare/manage preparation of high-quality reports, project documentation, and communications materials, as well as experience in working with projects funded by international donors (i.e. World Bank, ADB).

Experience: 20 Years

Intermittent Engagement (Person Months): 4

Hydrologist

M.Sc./M.Tech. in Hydrology, Water Resource, Civil Engineering with 10 years of relevant experience in monitoring and processing of hydro-meteorological data, statistical analyses of rainfall, water level and discharge data, rainfall-runoff modelling and flood forecasting.

Experience: 10 Years