Hydrogeologists without Borders
What, why and how.
Oklahoma International Water Conference
University of Oklahoma (October, 2011) Dave Bethune1, Cathy Ryan1, and John Cherry2
1Geoscience, University of Calgary, Alberta, Canada 2School of Engineering, University of Guelph, Ontario, Canada
HWB Problem statement: Major efforts to provide improved water supply in developing countries are
thwarted and often fail because of the inability to find and develop
groundwater resources - often due to the lack of hydrogeological expertise
What is hydrogeological expertise?
Geological mapping
Drilling & instrumentation
Field measurements &
gw sampling
Lab analyses & interpretation
Hydrogeological expertise is the integrated knowledge of geology,
groundwater flow, natural groundwater chemistry and
contamination towards the sustainable extraction of good quality
groundwater resources within the constraints of the hydrologic cycle
How does hydrogeology fit into the ‘Water and Sanitation’ Sector?
www.who.int
Hydrogeology fits into most, if not all, of these core activities…..
What are the primary aid activities in the WASH sector?
• Drilling wells • Building pit privies • Water treatment • Water distribution • Building schools • Medical facilities • hydrogeology?
Groundwater is increasingly important in the developing world
• gw provides ~50% of potable water supplies world-wide (UNESCO, 2003)
• Surge of gw used over the past 50 years (food demands, turbine pump, cheap energy, surface water supplies fully allocated)
• Many countries with distinct dry seasons, and or arid/semi arid countries (i.e. much of the developing world) are highly gw dependent
• Half the world’s mega-cities (and many large cities) rely solely or significantly on gw (UNESCO, 2006)
Q: How does hydrogeology fit into the WASH sector activities?
Water well witching, northern Nicaragua (photo D. Bethune)
Step 1: Desktop study: Aerial photography/Google Earth, regional geology info, existing water well records (since little subsurface info typically available)
Step 2: Field visit: Drive or walk around and assess terrain, soil, and geological factors to guide the water search (look for geologic outcrops, evidence of discharge (e.g. springs, seeps, phreatophytes)).
Step 3: Identify and find appropriate test drilling locations (including both geographic location and location, depth, and design of screen), preliminary contaminant source assessment.
Step 4: Identify and find the simplest, cheapest, most appropriate technology for creating wells in that particular geologic environment
Step 6: Drill test well(s), sample drill cuttings/cores to understand subsurface. Assess test well(s), sample water quality
Step 7: Iterative drilling of test wells, strategically selecting subsequent locations using on previous well(s) information to understand hydrogeology
Step 8: Accumulate sufficient site specific information from consecutive boreholes to understand the subsurface physically and geochemically.
Step 9: Assess contaminant sources in context of hydrogeologically appropriate well locations
Wells and latrines in close proximity (photos D. Bethune)
So, hydrogeology can be a complex and multi-stage process….. Q: Is hydrogeology fitting into the WASH sector activities appropriately? Q: Could a hydrogeology NGO enable the larger WASH sector through dialogue and collaboration?
Draft Mandate
HWB is primarily meant to enable the larger water,
sanitation and hygiene sector through dialogue and
collaboration.
Draft Mission
To integrate hydrogeology into aid efforts so that groundwater supplies are effectively found, developed, and protected, for
poor and disadvantaged people worldwide.
Draft Objectives
1. Provide hydrogeologic advice and guidance to field-based aid efforts,
2. Facilitate hydrogeologic education and training,
3. Advancement and awareness of appropriate groundwater technology.