Integrated water resource management (IWRM) research for mitigating drought and improving livelihoods within the Limpopo Basin Project 17

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Integrated water resource management (IWRM)
research for mitigating drought and improving
livelihoods within the Limpopo BasinProject 17
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Research Thrust

• To build evidence that improving water management
  through the IWRM paradigm improves rural
  livelihoods at the scale of the water management
  intervention
• Field scale farmers
• Local catchment scale communities, villages
• Sub-basin scale districts, provinces
• Basin scale transboundary

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Research Areas

• Improved understanding of water resources
• Farmer field-based action research (agriculture)
• Institutional Research

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Water Resources Research
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Rainfall and Runoff Variability
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Rainfall-Runoff Modeling

• Good simulation of runoff within catchments
• SWAT (Soil Water Assessment Tool) model
  application in Olifants
• Reduction in streamflow with inc. land cover
• HBVx Model in Mzingwane
• Interception an important process (56 in a dry
  season 2006/07, 32 of rainfall in normal
  season 2007/08)
• Stream flow driven by rapidly draining shallow
  groundwater
• Rainfall and runoff analyses (Pettitt Test) -
  change to drier regime since 1980

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Runoff Generation Modelling
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Hydrogeological Studies

• Small sand rivers
• Limitations
• Evaporation (lt 100 km2 give few months supply)
• Geology (seepage a stronger control than evap.)
• Large systems (Lower Mzingwane) WAFLEX Model
• Alluvial aquifer can store up to 38million m3 of
  water
• Additional 3600 ha of smallholder farms can be
  potentially irrigated with the water

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Lower Mzingwane
Max. smallholder irrigation from alluvial aquifers
Current
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Water Quality

• Challenges, esp. metal pollution
• Mozambique
• Major problems with metals Zn, Cu, Pb, Cd
• Design of a monitoring network done
• Zimbabwe
• Gold panning - potential Hg pollution in rivers
• Natural salinity in shallow groundwater
• Cadmium risk
• These studies and one from SA point to dangerous
  levels of Cd

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Agricultural Research
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Conservation Farming

• Zimbabwe
• planting basins, ripping, conventional spring and
  double ploughing
• Basin tillage showed lowest runoff
• Reduced runoff did not translate to highest yield
  under these conditions
• Modeling indicates that basins perform better
• Mozambique
• Basin tillage showed significant yield increase
  compared to conventional tillage

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Crop Water Productivity

• Crop simulation modeling in SA and field studies
  in Zimbabwe
• Increasing fertility (N) increases water
  productivity
• Crop water productivity (returns/mm)
• Use of the APSIM Model in simulating grain yield
  and crop water use
• APSIM performed well

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Rainwater Harvesting

• Mozambique
• Inventory showed 21 adoption of pits compared to
  flood recession, small dams and road runoff
• Zimbabwe
• Evaluation of rainwater harvesting technologies
  in the Mzingwane Catchment
• Dead level contours perceived as most effective
  by farmers, but measurements??
• Soil type and resource status were important
  factors
• South Africa
• Chololo pits increased maize grain yield compared
  to conventional farming

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Supplemental Irrigation

• Rain fed vs supplemental irrigation in South
  Africa
• Drought year moisture deficit during flowering
  stage was reduced
• Supplementary irrigation raised yield from 0.6 to
  2.0 t/ha

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Soil Salinity Studies- Chokwe

• Salinity management strategies in irrigation
• Salinity reduces yield and hydrological processes
  play a role potential to model the system??
• Scenario analysis to improve irrigation
  performance and efficiency

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Institutional Research
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Models of Catchment Planning

• Mzingwane Catchment Council
• Changes in the structure of the model
• Understanding the role of women
• Outline plan, addressing weaknesses that were
  identified by PhD research
• Water chemistry results being taken seriously
• BUT, confusing messages on CA, dead level
  contours
• MCC appreciates the work of Phase PN17 so far

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Evaluating Stakeholder Participation

• Water User level -Lowest to district/sub-catchment
  
• Water access
• Private, communal, generally poor access at user
  level
• Institutional processes
• New institutions are a manifestation of
  negotiation processes by users
• Outside intervention dictates the processes
• Rights creation
• Appropriative rights the most common form of
  creation
• Communal rights do not mean much without a
  legitimate and acceptable enforcer

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Institutional Mapping and Performance

• Water resource management at the local level
  Mzingwane
• Identifying practices, linkages and weaknesses
• CA and donor influence
• Water resource planning
• The importance of the culture based normative
  framework in water resources management
• Approaches to planning for water resource
  bottom up approach more relevant

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MainstreamingCapacity Building (CB)

• Outreach through capacity building in the
  communities and institutions
• CB was not follow-up or not a later add-on to
  research
• CB is mainstreamed
• Integrated into project from planning stage
  onwards
• Involving all scientists
• Involving farmers and management agencies

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Capacity Building Knowledge Outputs

• 32 MSc students completed 2 in progress
• 8 females, 25 NARES staff
• PhD students
• One student has graduated
• 3 more students likely to complete by Dec 2009
• 5 farmer groups supported
• Publications 24 articles, 12 chapters, 81 conf.
  papers
• Workshops 5 basin level, 8 catchment level
  workshops

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Decision-Support Integrative Modelling

• Coupling models into a decision support tool -
  ICHSEA 
• ArcView 3.3 interface
• SWAT output to PARCHED-THIRST, its output to
  OLYMPE
• Uncertainty analysis in progress
• Scenarios full-scale additional irrigation,
  supplementary irrigation, different water sources
  
• Strategic tool, not an operational tool

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Constraints

• Rainfall variability and drought
• Staff turnover and brain drain
• Politico-economic conditions in Zimbabwe
• Budget constraints

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Thank you!!!