Republic of Kenya
Ministry of Environment, Water and
Natural Resources
Groundwater Resources Investigation
for Drought Mitigation in
Africa Programme
Radar Technologies International
Survey contractor: Implemented by:
Client: Contribution to the national
development strategy: Financed by:
Advanced Survey of Groundwater Resources of
Northern and Central Turkana County, Kenya
August 2013
©Natalie Walther
JAPAN Official Development Assistance
Peter Manyara National Programme Coordinator for Kenya, UNESCO-GRIDMAP
Contact: [email protected]
Table of Contents
• About UNESCO & IHP
• The Turkana Groundwater Survey and Mapping – Overview
– Objectives
– Methodology
– Validation
– Results and findings
– Recommendations
– Survey outputs
• UN IYWC 2013
ABOUT UNESCO
• Established in 1945, the United Nations Educational, Scientific and Cultural Organization
(UNESCO) contributes to peace and security by promoting international collaboration through
education, science, and culture.
UNESCO strives to build networks among nations that enable this kind of solidarity, by:
• Mobilizing for education: access; quality; rights; development.
• Building intercultural understanding: cultural diversity; World Heritage
• Pursuing scientific cooperation: early warning systems; trans-boundary waters; relations
• Protecting freedom of expression: condition for democracy, development and human dignity.
UNESCO-IHP
• The only intergovernmental programme of the UN system devoted to water research, water
resources management, and education and capacity building; Tailored to States’ needs
• it is implemented in six-year phases – allowing it to adapt to a rapidly changing world.
IHP-VII: Water Dependencies: Systems under Stress and Societal Responses (2008-2013)
• This phase continued to lead international hydrological research, facilitate education and capacity
development and enhance governance in water management towards meeting the UN MDGs on
environmental sustainability, water supply, sanitation, food security and poverty alleviation.
IHP-VIII: Water Security: Responses to Local, Regional, and Global Challenges (2014-2021)
• The new phase follows the Millennium Development Goals (MDGs) era and envisions new
challenges to be set in the SDGs. During its eighth phase, IHP aims to improve water security in
response to local, regional, and global challenges.
The International Hydrological Programme (IHP)
IHP-VIII, 2014–2021
In response to the priorities and needs of Member States, IHP-VIII focuses on six knowledge
areas, translated into themes:
IHP-VIII, 2014–2021
• Focal Area 2.1 - Enhancing sustainable groundwater resources management
• Focal Area 2.2 - Addressing strategies for management of aquifers recharge
• Focal Area 2.3 - Adapting to the impacts of climate change on aquifer systems
• Focal Area 2.4 - Promoting groundwater quality protection
• Focal Area 2.5 - Promoting management of transboundary aquifers
THEME 2: GROUNDWATER IN A CHANGING ENVIRONMENT
IHP PROGRAMMES
• HELP: Hydrology for the Environment, Life, and Policy
• FRIEND: Flow Regimes from International Experimental and Network Data
• GRAPHIC: Groundwater Resources Assessment under the Pressures of Humanity and Climate Change
• G-WADI: Global Network on Water and Development Information in Arid Lands
• IDI: International Drought Initiative
• IFI: International Flood Initiative
• ISARM: Internationally Shared Aquifer Resources Management
• ISI: International Sediment Initiative
• JIIHP: UNESCO-IAEA Joint International Isotope Hydrology Programme
• PC-CP: Water for Peace: From Potential Conflicts to Cooperation Potential
• UWMP: Urban Water Management Programme
• International Knowledge, Research, and Policy Initiative on Water Quality
• WHYMAP: World Hydrogeological Map
CROSS-CUTTING PROGRAMMES AND INITIATIVES
Advanced Survey of Groundwater
Resources of Northern and Central
Turkana County, Kenya
OVERVIEW
Target area
Beneficiary
Executioner
Budget
Donor
Duration
Contractor
National framework
Regional frameworks
Parent Project
Scientific review
Northern and central Turkana County
Ministry of Environment, Water and Natural Resources
UNESCO
$700,000 ($150,000 for exploratory drilling)
Japan (Official Development Assistance)
July 2012 – June 2013
Radar Technologies International (RTI)
Kenya Vision 2030
GRIDMAP, IGAD
Strengthening capacity to combat drought and famine in the
Horn of Africa (Ethiopia, Kenya, Somalia), $1.5 million
Technical Scientific Committee (Kenya)
1. To survey and assess the groundwater potential of North-central Turkana County
2. To identify and assess a maximum quantity of new clean groundwater resources
for populations, with particular focus on Lodwar, Lokichogio, and Kakuma
3. To assess the potential of groundwater for development, with a focus on both
shallow and deep structures
36,000 km2
OBJECTIVES
Lokichogio
Kakuma
Lodwar
METHODOLOGY
Landsat 7 Processing
Elevations Slopes
SRTM Processing: Elevation & slope evaluation
Lithological contrasting
Water dynamics evaluation
Surface Drainage Catchment boundaries and
harvesting
Geological assessment
Soil Type Classification
METHODOLOGY
WATEX Radar Processing and classifying shallow groundwater (0-80 m)
METHODOLOGY
WATEX Shallow Aquifer Groundwater Occurrence Model (SAGOM):
Classifying shallow groundwater (0-80 m)
6.25
m
Negative Negative Negative Negative Positive
6.25
m
Negative Negative Negative Positive Positive
6.25
m
Negative Negative Positive Positive Positive
6.25
m
Negative Negative Positive Positive Positive
6.25
m
Positive Positive Positive Positive Positive
6.25 m 6.25 m 6.25 m 6.25 m 6.25 m
Pixel resolution (39 m2)
Pixel Color Occurrence potential at location
Yellow Minimum of 90%. These pixels represent
fracture discharges in alluvial sediments,
or pure alluvial aquifers.
Red 75% probability of aquifer presence if
combined with a conductive fracture.
Light blue 30% probability of aquifer presence if
combined with a conductive fracture.
Green 25% probability of groundwater
occurrence, located over hills and
mountains. Wells in these pixels should
only be drilled with the presence of a
conductive fracture
Black / dark 0-5%, minimal occurrence potential, likely
to be dry or have little potential for
groundwater occurrence.
Groundwater potential color coding
METHODOLOGY
Mapping shallow groundwater (0-80 m)
WATEX fracture mapping and classification
WATEX Landsat and SRTM
processing for fractures
WATEX Fracture classification,
Conductive (yellow), non-conductive (blue)
METHODOLOGY
Mapping shallow groundwater (0-80 m)
Interpretation of gravimetric data Interpretation of seismic data
WATEX Deep Aquifer Model (DAM):
Inferring deep-seated aquifers (100 - 3000 m)
METHODOLOGY
Mapping shallow groundwater (0-80 m)
Regional deep aquifers
WATEX Deep Aquifer Model (DAM):
Inferring deep-seated aquifers (100 - 3000 m)
METHODOLOGY
Lotikipi Aquifer (330m) Lodwar Aquifer (126m)
WATEX accuracy level in Turkana: > 94% for shallow alluvial groundwater occurrence
UNESCO Validation Results
MODEL VALIDATION
Total Groundwater Resources in Northern-central Turkana County
Aquifer regime Est. Recharge
(MCM / yr)
Est. Storage
Capacity (MCM)
Shallow alluvial systems (0-100 m) 2,085 2,085*
Deep-seated systems (100-800 m) 1,362 248,250
3,447 250,335
* In absence of localized data at the regional scale, a conservative estimate for the cumulative storage capacity
of shallow alluvial assumes the same amount of annual recharge
RESULTS & FINDINGS
Deep-seated Aquifer Systems in Northern-central Turkana County
* Estimate for recharge of Lodwar Aquifer is not given due to insufficient data on Turkwel River recharge dynamics.
Aquifer system Recharge
(MCM/yr)
Storage
capacity
(MCM)
(1) Lotikipi Basin 1,200 207,500
(2) Lodwar Basin -* 10,000
(3) Gatome Half-graben 61 17,250
(4) Nakalale Half-graben 59 7,000
(5) Kachoda Half-graben 21 6,500
Total 1,362 248,250
RESULTS & FINDINGS
Groundwater Potentials for Priority Areas in Northern-central Turkana County
Lodwar
• Groundwater
potential (1,292
MCM per year)
• No seasonal
groundwater level
variation in the
boreholes below
alluvial deposits
• Endowed with the
deep Lodwar Basin
Aquifer (10 BCM)
Kakuma
• Groundwater potential,
within 10km2, (51 million
m3/year
• Current water withdrawals
only 2.5% of available
groundwater
• Best options for shallow
boreholes (<100 meters) is
to drill within the fracture
corridor of the Tarash River
identified by the study
• Located 25 km south of the
southern portion of Lotikipi
Basin Aquifer
RESULTS & FINDINGS
Lokichogio
• Groundwater potential,
(107 million m3/year)
•
• Few viable options
available within 10 km
of town
• Located 25 km west of
the western portion of
Lotikipi Basin Aquifer
• The Government of Kenya should take measures to ensure the dissemination of information and tools to stakeholders.
• GOK, UNESCO and other partners should expand and build the cadre of
skilled professionals who can utilize the survey tools.
RECOMMENDATIONS
• Kenyan government and its affiliated research institutions should conduct
additional studies in order to achieve a more comprehensive understanding
of these resources and their full potential and vulnerabilities.
• Expand the WATEX study approach to the rest of Turkana and Kenya in
order to benefit other regions. Turkana can be a model for other counties.
• Study socio-economic potential of groundwater, particularly deep aquifers
• Continue hydrogeological research and modeling of deep structures,
including the exploration of the un-confirmed structures, and more boreholes on the confirmed aquifers.
Research
Survey tools and maps
• The skills/capacity of the drilling industry is inadequate for carrying out
reliable and sound exploratory drilling.
• A major campaign should be launched to build the capacity of the industry as
a whole, and reduce the inefficiencies in the market.
• It is important if the Government can acquire specialized drilling equipment for exploratory drilling of scientific boreholes.
Drilling capacities
• Develop exploratory boreholes (Lotikipi and Lodwar) to be able to provide
immediate water supply to local communities.
• Drill up to 200-500 shallow alluvial boreholes in high-potential areas identified
by this survey.
RECOMMENDATIONS
• Kenyan authorities should establish a limit on abstraction rates for both the
Lotikipi and Lodwar Aquifers. WRMA can establish the rates for abstraction
for both normal and emergency situations.
• Kenyan authorities are recommended to undertake aquifer zoning and
gazette adjacent land to protect the aquifers from harmful activities.
• Establish a modern aquifer monitoring system to monitor the Lotikipi and
Lodwar aquifers.
Aquifer management
Short term projects
SURVEY OUTPUTS
Full Technical Report
(August 2013) High Potential Groundwater Target Map;
Groundwater Recharge Map;
Soil and Vegetation Map (1:200,000) GIS Database of
groundwater resources
!
Groundwater Exploration
Navigation System (GENS)
RADAR TECHNOLOGIES
INTERNATIONAL
Technical Field Manual for
Groundwater Targeting
NORTHERN-CENTRAL TURKANA COUNTY
Technical field manual for
groundwater targeting Practical field training
UN IYWC 2013
• Aims at raising awareness about opportunities in water cooperation.
• UNESCO was officially designated by UN-Water to lead the preparations for this IY in 2013.
• Water cooperation: has multiple dimensions including cultural, educational, scientific, religious,
ethical, social, political, legal, institutional and economic aspects.
• A multidisciplinary approach is essential to grasp the many facets implied in the concept and
to blend such parts into a holistic vision.
• A common understanding of what the needs and challenges are around water is required in order
for water cooperation to be successful and long-lasting: building a shared consensus
• Participation from a wide range of parties including NGOs, IOs, UN Agencies, National and
Regional Institutions, and Academia among others is expected and encouraged.
UN International Year of Water Cooperation 2013