Request for Expression of Interest (EOI): Hydrogeology Assessment for Solarizing Community Water Supply Systems -Winrock International, Ethiopia

Technical Proposals Due to Winrock: January 30 2026

BACKGROUND

Winrock’s Solarizing Community Water Supply project, funded by the Conrad N. Hilton Foundation, aims to test commercial models for replacement of diesel community water pumps with solar pumps. The project is facilitating three-year lease-to-own contracts between rural water utilities and private solar developers to solarize diesel driven solar pumping systems in communities across Ethiopia.

OBJECTIVE OF THE CONSULTING SERVICES

The project is seeking consulting services, including at least one woman on the team, to assess the hydrogeology, water supply infrastructure, water quality, and water demand in a total of 15 – 20 communities in South Ethiopia and Central regional states. Data generated by the consultant will inform the selection of priority sites for replacement of diesel pumps with solar pumps; therefore, it is critical that the data are accurate and complete.

Selection of a consulting firm will take place in two steps:

• Step 1: Submit a technical proposal in response to this solicitation.
• Step 2: Selected firms will be invited to submit a financial proposal in February based on specific sites in South Ethiopia and Central regional states.

EXPECTED RESULTS

Assessment of the water supply infrastructure, water supply capacity, and water quality at 15 – 20 community diesel pump sites, including the following for each community:

• Create a map of the water system, including borehole/spring, reservoir, and distribution points
• Estimate the current daily water demand in each community
• Inspect the quality and capacity of reservoirs, elevated water tanks, water distribution lines, drive pipe (from the pump to the reservoir), public water taps, and diesel generator.
• Conduct a test of the yield capacity of each borehole, and determine the static level
• Take water samples and report on water quality testing results from an accredited body
• Summarize and recommend sites for solarization based on the data collected.

METHODOLOGY, TASKS, AND DELIVERABLES

Winrock seeks a consulting firm (Consultant) with the necessary technical specialties which can conduct the assessment in a total of 15 – 20 communities within a maximum of 35 person-days. The Consultant will work closely with Winrock’s Project Coordinator and coordinate with the local Water Committee in each site. The assessment includes the following steps:

Introduction to the Water Committee and community representatives in each site

Winrock will coordinate with the relevant woreda to introduce the Consultant and the scope and goals of this assessment to the Water Committees and community representatives, including women leaders, in each site.

Deliverable 1: Within one week of contract signing, submit a final methodology for this assignment, a timeline, and a proposed itinerary for visiting the community sites

Informational meeting with Water Committee and community representatives

The Consultant should conduct a meeting with the Water Committee and community representatives in each site to ask questions as needed, including questions about water demand, creating a map of the water system infrastructure, and collecting copies of records of water consumption including volume of water sold, number of households served by each public water point, and number of household water connections.

Data collection and analysis at community sites

During site visits, the consultant should be accompanied by a Water Committee representative with detailed knowledge of the community water system. All field data should be entered into a spreadsheet which will be provided by Winrock.

Hydrogeology Analysis

At each site, the Consultant should determine:

• Head (height from water level in borehole to top of borehole, plus height from top of borehole to reservoir water inlet) (m)
• Dry season depth to water table (m) (when pump has not been run yet on that day)
• Pump discharge rate (liters/s): To come up with a reasonable estimate, the consultant is expected to pump the water for several hours and take readings from the existing water meters to show the current productivity/performance of each well

Water Supply Infrastructure Assessment

Borehole and surrounding area

• Size of the borehole (diameter)
• Condition (functional, minor repairs needed, not usable)
• Suitability of surrounding conditions for solar array

Diesel Generator

• Altitude at diesel generator (m)
• Power rating
• Number of years in operation
• Condition (functional, minor repairs needed, not usable)
• Notes on condition of diesel generator

Drive Pipe:

• Length (m)
• Thickness (mm)
• Diameter (mm)
• Type (plastic, galvanized iron)
• Condition (functional, minor repairs needed, not usable)
• Notes on condition of drive pipe

Distribution pipe branches

• Indicate distribution branches on map and list by number
• Diameter (mm)
• Type (plastic, galvanized iron)
• Number of community taps
• Condition (functional, minor repairs needed, not usable)
• Notes on condition of pipe branches

Public water taps:

• Indicate public taps on map and list by number
• Number of taps at each location
• Number of people served per day
• Condition (functional, minor repairs needed, not usable)
• Notes on condition of public taps

Reservoir:

• Conduct physical measurements of reservoir height and circumference, including photos of the reservoir
• Note the condition of the reservoir (functional, minor repairs needed, major repairs needed, not usable)
• Note the condition of reservoir outlets and gate valves, including photos
• How many times per day is the reservoir filled?
• What is the depth of water in the reservoir when it is filled during the dry season? (m)
• What is the depth of water in the reservoir during the rainy season? (m) (ask WASHCO)

Water Supply System Component Sufficiency:

• Overloaded? (yes/no) (if yes, explain which component(s) are overloaded)

Water Quality Analysis

• Collect a water sample at each site and have it analyzed for basic water quality parameters as specified in the spreadsheet provided by Winrock.
• Water quality parameters must be based on Government of Ethiopia rules and regulations for drinking water.
• Laboratory analysis must be done by an accredited body in accordance with Government of Ethiopia rules and regulations; laboratory testing results must be certified.

Deliverable 2: Completed spreadsheet detailing the current state of the water demand, hydrogeology, water supply infrastructure, and water quality in each of 15- 20 community sites.

Meet with Winrock to present results of the assessment of the first two sites before assessing the remaining sites

The Consultant should present results to the Winrock project team after the first two sites have been assessed, to determine whether any adjustments need to be made to the spreadsheet.

Presentation of results

The consultant will present the assessment results for all 15 – 20 sites to Winrock and will undertake one round of edits as requested by Winrock before submitting the final Powerpoint slides and spreadsheet. The consultant will present the final results at a validation workshop led by Winrock, which will include key local and regional government stakeholders. Once Deliverables 2 and 3 are approved, a final invoice may be issued.

Deliverable 3: A brief Powerpoint presentation including photos of key structures at each site, summarizing the assessment findings and making a recommendation of sites where conditions are suitable for replacing the diesel community water pump with a solar pump.

Formatting of deliverables:

• All tables and data must be submitted to Winrock
• Presentations must be in Powerpoint, using Winrock’s slide template
• All data values must specify the units (e.g. depth in meters, etc.)
• All deliverables must be in English

REQUIRED QUALIFICATIONS

Winrock seeks a consulting firm with experts whose qualifications are described below. The team should include at least one woman. At least one of the two experts (Lead Consultant, Technical Expert) should have experience with solar water pumps.

Lead Consultant

Technical Expert

Required Skills