ToR - for Hydrogeological Investigation, Aquifer Mapping and Managed Aquifer Recharge (MAR) Planning under the Project "Building Water Security...

Apply by: 04 Sep 2026

Monitoring, Evaluation, Policy, Research

Water For People-India Trust

Terms of Reference (ToR) for Hydrogeological Investigation, Aquifer Mapping and Managed Aquifer Recharge (MAR) Planning under the Project "Building Water Security and Climate Resilience in Sagar Block, Sundarbans, South 24 Parganas, West Bengal"

Background

Water For People India Trust is a public charitable trust registered under the Indian Trust Act, 1882, dedicated to improving the quality of life of vulnerable communities through sustainable Water, Sanitation and Hygiene (WASH) services and Integrated Water Resource Management (IWRM). The organization works closely with government agencies, research institutions, civil society organizations, and local communities to promote water security and climate resilience through evidence-based and community-led approaches.

Sagar Block in the Indian Sundarbans is highly vulnerable to climate change, facing challenges such as groundwater salinity, freshwater scarcity, coastal erosion, tidal flooding, and frequent cyclones. To address these issues, Water For People is implementing the project "Building Water Security and Climate Resilience in Sagar Block" , which adopts an integrated approach combining water resource management, ecosystem restoration, resilient livelihoods, and inclusive WASH interventions.

The project focuses on four Gram Panchayats while generating scalable solutions for the entire Sagar Block and the Sundarbans region through government convergence and the Technical Support Unit (TSU). As part of this initiative, a comprehensive hydrogeological study is proposed to assess aquifer systems, groundwater availability and quality, seasonal groundwater dynamics, and identify suitable locations for Managed Aquifer Recharge (MAR) and other sustainable water security interventions

B. Objectives

The overall objective is to generate scientific evidence for planning sustainable groundwater management and climate-resilient water resource interventions.

Specific objectives include:

Assess the hydrogeological conditions of the project area.

Prepare detailed aquifer maps for the four Gram Panchayats.

Understand groundwater behaviour during one complete hydrological cycle (Pre-Monsoon and Post-Monsoon).

Identify potential sites for groundwater replenishment and sustainable aquifer management.

Assess groundwater quality with emphasis on salinity and drinking water suitability.

Support planning and design of recharge structures, including Recharge Shafts and other groundwater augmentation measures.

Develop a hydrogeological database to support long-term groundwater monitoring and climate-resilient water resource planning.

C. Scope of Work

The selected agency shall undertake the following activities:

1. Desk Review and Data Compilation

Review available geological, hydrogeological, geomorphological, and groundwater data.

Compile secondary data from CGWB, SWID, PHED, IMD, and other relevant agencies.

Prepare GIS base maps of the study area.

Review historical groundwater level and groundwater quality data.

2. Hydrogeological Field Investigation

Conduct reconnaissance surveys in all four Gram Panchayats.

Carry out geomorphological and drainage mapping.

Inventory and GPS mapping of wells, ponds, canals, and other water sources.

Assess groundwater use patterns and existing water supply systems.

Identify groundwater dynamics

3. Aquifer Mapping

Prepare GIS-based aquifer maps for all four Gram Panchayats.

Delineate aquifer extent, geometry, thickness, and hydrogeological characteristics.

Map groundwater occurrence, water table configuration, and groundwater flow direction.

Identify groundwater potential zones and groundwater vulnerability.

Identify salinity-affected aquifer zones.

Conduct aquifer mapping for one complete hydrological cycle, including: Pre-Monsoon Assessment & Post-Monsoon Assessment

Analyse seasonal groundwater fluctuations and aquifer recharge behaviour.

4. Geophysical Investigation (Vertical Electrical Sounding - VES)

Design and conduct Vertical Electrical Sounding (VES) surveys across the study area.

Collect and interpret resistivity data.

Identify aquifer layers and estimate aquifer depth and thickness.

Delineate freshwater and saline groundwater zones.

Identify suitable groundwater recharge locations.

Finalize the number and location of VES points in consultation with Water For People.

5. Groundwater Monitoring

Monitor groundwater levels during the pre-monsoon season.

Monitor groundwater levels during the post-monsoon season.

Analyse seasonal groundwater fluctuations.

Compare seasonal groundwater level variations.

6. I dentification of Managed Aquifer Recharge (MAR) Potential

Identify suitable locations for Managed Aquifer Recharge (MAR) interventions or other feasible recharge options.

Assess site suitability based on aquifer characteristics, groundwater depth, soil and geological conditions, salinity levels, and land suitability.

GIS Database Development

Develop GIS layers for geology, geomorphology, drainage, land use/land cover (LULC), aquifer distribution, groundwater levels, recharge zones, MAR potential zones, and VES locations.

Submit all GIS maps, spatial datasets, and project files in editable digital formats (e.g., shapefiles and geodatabases).

D) Deliverables

The selected agency shall submit the following deliverables:

Inception Report detailing the study methodology, work plan, timeline, and survey approach.

GIS Base Maps of the study area.

Hydrogeological Survey Report covering field investigations and hydrogeological assessment.

Vertical Electrical Sounding (VES) Survey Report with data interpretation and aquifer characterization.

GIS-Based Aquifer Maps (2D) for the four Gram Panchayats.

Integrated Groundwater Potential and MAR Suitability Maps depicting groundwater potential, freshwater recharge potential, MAR suitability, freshwater lens vulnerability, salinity risk, rainwater harvesting suitability, groundwater development potential, and recommended intervention sites.

Pre-Monsoon and Post-Monsoon Groundwater Assessment Reports, including groundwater level fluctuation analysis.

Editable GIS Database, including all spatial datasets, maps, VES data, raw field data, photographs, and associated project files in editable digital formats.

Phase I Report – by January 2027: Hydrogeological Report covering the initial field investigation and assessment.

Phase II / Consolidated Report - Submission by the end of August 2027 – after one complete hydrological cycle: Integrating the complete hydrogeological study, aquifer mapping, seasonal groundwater assessment, and identification of selected wells for long-term monitoring , along with final recommendations.

E. Expected Outcomes

The study is expected to deliver:

Scientific understanding of the hydrogeological setting of the project area.

Comprehensive aquifer maps for all four Gram Panchayats.

Improved understanding of seasonal groundwater dynamics.

Identification of freshwater-bearing aquifers.

Delineation of groundwater recharge and discharge areas.

Identification of suitable Managed Aquifer Recharge (MAR) locations.

Technical recommendations for Recharge Shaft implementation.

Decision-support tools for climate-resilient water resource planning.

GIS database for long-term groundwater monitoring and future project planning.

F. Timeline

ToR Issued on August, 2026

Proposal submitted no longer than Sept 4 th , 2026

Winning proposal selected: Sept 11 th , 2026

Contract signed: August 15 th , 2026

Begin work/Kick off meeting: August 21 st , 2026

The assignment is expected to commence from October 2026 and will cover one complete hydrological cycle .

I. SUBMISSION REQUIREMENTS

Interested consultants/Agencies must provide information indicating that they are qualified to perform the service, along with cost information.

Proposal must be submitted