Terms of Reference HYDROGEOLOGICAL AND GEOPHYSICAL INVESTIGATION FOR BOREHOLE SITTING
Request for consultancy services (REF: Hiran/Buloburte SHF – WASH/2019
Terms of Reference
HYDROGEOLOGICAL AND GEOPHYSICAL INVESTIGATION FOR BOREHOLE SITTING
Reference: SCI – Ground Water Consultancy
Area of Interest: Hydrogeological and geophysical investigation for borehole sitting
Location: Buloburte Hiran, Somalia
Position Type: Consultant/Firm
Duration: 1 month
Start date: February 2019
Save the Children has been making a difference in children’s lives in more than 120 countries. We are the world’s largest independent child rights organization, underpinned by a vision in a world in which every child attains the right to survival, protection, development and participation. Our mission to inspire breakthroughs in the way the world treats children, and to achieve immediate and lasting change in their lives.
To ensure delivery of this mission, Save the Children collaborates with local governments, multilaterals, grassroots, non-governmental organizations and others to identify and address supply and demand-related bottlenecks in both humanitarian and development contexts. Save the Children has been engaged in the WASH sector in Somali for more than 20 years.
As severe drought grips most parts of Somalia, Lack of safe drinking water access has contributed to staggering levels of diarrhoeal diseases, particularly among the young, the immune-compromised, and the poor. Unsafe water sources complemented by poor sanitary environment are a major cause of malnutrition throughout Somalia.
The existing water sources in Buloburte Hiran are already overstretched due to the effects of drought on the ground water levels. While water points do exist, many have fallen into disrepair where communities simply do not have the resources (funds, skills) to repair them. In addition, the continued influx of more IDPs due to floods and persistent floods as well as closure of WASH programs by some of the humanitarian agencies is putting pressure on the existing water supply system. The current volume of water supplied cannot meet the existing demand. Many of the households cannot meet the recommended 15 liters per person per day as per the Sphere standards. In addition, the recurrent seasonal floods in Buloburte have also worsened the situation whereby almost all the communities along the riverine areas depend on the river as their source of water. It’s in this grim reality that Save the Children is planning to drill a new boreholes in Buloburt which will serve more than 5000 people and up to 9000 people in 20 years (taking into account an average urban growth rate of 4% per annum). By targetting a minimum of 30 litres/p/day, the sustainable discharge rate per day should be above 150 m3 per day, equivalent to 13 m3/h over 12 hours pumping per day without undesired effect –depletion of the aquifer or changes in water quality. Save the Children will engage a consultant firm to carry out a borehole sitting study in the selected location where the new borehole is to be constructed.. The objective of this survey is to ascertain the drilled borehole will meet or exceed the water demand for the next 20 years.
Overall objectives OF THE HYDRO-GEOLOGICAL SURVEY
- To conduct hydrogeological and geophysical investigation for the optimal sitting of a drinking water borehole in Hiran (Buloburte)
scope of THE WORK
The Consultant is expected to use both secondary and primary data in the exercise.Secondary data will involve desk studyof available information/data on existing boreholes, drill logs, reports and maps while primary data will be obtained by carrying out field reconnaissance and measurements of existing boreholes and geophysical prospecting within the studied area using a combination of geophysical methods as below described.. : The outcome of the consultancy will be a detailed hydrogeological survey report giving details of the findings and recommendations
SURVEY APPROACHES REQUIRED:
The hydrogeological/geophysical investigations will be carried out in a multistep approach:
- Desk study: Review of existing data, topographical maps, satellite images, existing studies and borehole site investigations in the area, geological reports and maps (if available), borehole and surface water records, etc.
- Hydrogeological fieldwork: Detailed reconnaissance survey of project area. (GPS coordinates/P codes, water level measurements, condition of these boreholes, usage and performance, estimation of the hydraulic characteristics from existing well test and aquifer test, ), vertical geophysical prospecting at known boreholes for calibration purpose : measurement of the real resisitivities of geological formations based on the existing borehole logs.
- Geophysical measurements vertical and horizontal electric sounding, vertical electric 2D tomography, EM method and possibly seismic refraction method are recommended for this assignment.
- Analysis and interpretation of field data for selection of potential sites for drilling
- Presentation of the results to hydrogeologist/geologist experts from SC and Ministry of Energy and Water Resource for validation of the best possible site
- Field validation of the site to ensure there is no obstacle for drilling (explaination and agreement with the community, no land tenure or future urban planning issues, access to drilling machine, risk of contamination, …)
- The outline table of contents of the final report will be as follows:
- Executive summary (1 pages)
- Introduction, review of previous studies and hydrogeological information of the studied area, including history of groundwater depletion or known changes in quality : mineral content including unharmful –iron- and harmful -fluorides, nitrates…-; and toxic elements such as arsenic ; bacteriological pathogens.
- Geology and hydrogeology (incl. Inventory of positive and negative boreholes, aquifer characteristics –storage and hydraulic- and well characteristics –sustainable discharge rate- based on on available data., and water quality))
- Calibration of the geophysical instrument at known boreholes (yield, log) for the geophysic characterization of the geological formations, including the aquifer(s).
- Methods of investigations, including combination of geophysical methods.
- Geophysical prospecting on different sites.
- Interpretation and comparison of studied sites: aquifer and borehole potentials, Most suitable drilling site and justification , target aquifer(s) for drinking water production, mentioning assumptions, risks and risk management.
- proposed drilling method, with equipment characteristics (incl. estimation of the casing and screen positions)
- Simplified Environmental and societal impact of the drilling and required risks reduction measures
The consultant/firm is expected to deliver:
- An inception report presenting 1/ the steps and methodology for the assignment against the present Terms of Reference, and justifiying any difference or discard with the TOR ;
- the implementation plan and requirements for the site investigation. A brief note with the recommended sites selected for borehole reconnaissance and geophysical survey, for SC’s validation before the field deployment,
- The presentation of the field work, interpretations and conclusions to the SC and the water authorities.
- The final report
|ACTIVITY DESCRIPTION||Time Line|
|Secondary data collection, review of field documents on existing boreholes and studies, and analysis|
|Key informant interviews (face to face or remote)|
|Field work: Reconnaissance of existing boreholes, geophysical prospecting and final validation of the selected site|
|Presentation to SC and authorities, Reporting|
Save the Children seeks to invite qualified consultants/firms who meet the following requirements to submit their detailed narrative and financial proposal on how to undertake the assignment.
- Technical proposal on how the assignment will be conducted including methodologies, data analyses and interpretation, reports and schedules. ( List software to be used for analysis)
- Proven field technical and field experience of Consultant with Master’s degree in geology, hydrology, engineering geology, physical, or earth science, or in any related field and having good experience of working in this sector.
- Consultancies performed in the last 10 years especially with reference letters for each hydrogeological surveys consultancy
- Proof of availability of all the equipment’, personnel and ability to mobilize them on short notice (Include list of equipment, Brand/Manufacturer, CVs of the personnel) to perform the survey.
- Submit a detailed financial proposal including all professional fees, report costs and subsistence costs. Please note all costs must be broken down into details ( no lump sums, no contingencies etc)
The consultant/firm will be responsible for their own security; insurance while in the field and Save the Children will not be responsible for any injuries or damages incurred during the assignment. The costs submitted must be inclusive of all anticipated expenses.
SC will select the geophysical surveyor together with Ministry of Energy & Water Resources at Federal Government of Somalia based on their technical competence and experience.
MANDATORY SECURITY TRAINING
The consultant shall be expected to go through mandatory on-line security training and submit the certificate of completion to SC before the commencement of the task. Failure to deliver this will lead to an automatic disqualification. SC will advise on the security plan on appointment. SC will cater the security during the survey days in Buloburte .
Interested parties must submit their applications by email referenced under title
HYDROGEOLOGICAL AND GEOPHYSICAL INVESTIGATION FOR BOREHOLE SITTING
Please send copy of your complete documentations (experience, technical proposal, lead-time, profile and relevant CVS) to CSS.LOGISTICS@savethechildren.org not later than 15th February-2019 at 10:00AM.
Any application not meeting the above requirements shall not be considered.
Save the Children will consider applications from both individuals and firms. Applications shall clearly identify a team leader, who will be the sole responsible to deliver the outputs of the assignment.
Consultants are requested to submit a proposal with a cover letter and must mention their expected total remuneration for this assignment.
Applications should include:
- A proposal to the above Terms of Reference including methodology, schedule, budget.
- A financial offer including daily fees in US Dollars
- Up-to-date curriculum vitae(s) of the lead consultant and relevant team members,
- Description of available equipment for the assignment,
- Evidence of past experience in undertaking similar assignments (three most recent documents preferred) of similar works done,
- Three (3) references of previous assignments.
Only shortlisted applications will be contacted.