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A collaborative project by:Jomo Kenyatta University of Agriculture
and TechnologyWater Resources Management
Authority(Tana Region)University of the Sunshine Coast of
AustraliaNames of project collaborators:
1. John Ng’ang’a G…….. WRMA/JKUAT2. Prof. Bancy Mati ………JKUAT3. Mr. S. Wangombe……..WRMA-TANA4. Mr. Robinson Kimari …WRMA-TANA
A SCOPING STUDY ON TANA RIVER BASIN WATER RESOURCES MANAGEMENT
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INTRODUCTION
The Tana BasinThe Tana basin covers an area of 126,026 km2_ which is about 20% of the land area of Kenya.
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INTRODUCTION The Tana River is the biggest and longest river in the country, traversing 1,012 km from its source on both the Nyandarua Range (3,990 m) and the Mt. Kenya (5,199 m above sea level) to the Indian Ocean near Kipini.
Its tributaries emanate from Mt. Kenya, the Aberdares and the Nyambene Hills forming a dendritic drainage system.
The basin is divided into three; The Upper Tana, Middle-Tana an
Lower Tana.
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The upper Tana provides water for small agricultural holdings and supplies Nairobi's water supply and hydroelectricity through 4 dams.
The middle provides water to small communities and cattle in a semi-arid area, while,
The lower Tana meets the coast near Lamu which currently accesses water from dunal aquifers.
A key issue is to ensure that river water meets human needs from the upstream to downstream of the catchment while maintaining environmental flows.
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As water scarcity has increased globally, water allocation plans and agreements have taken on increasing significance in resolving local, regional and international conflicts over access to water.
Water resources are faced with a lot of challenges that include
growth in water abstractions growth and change in the economy, leading to a wider variety of water users with different water demands
decline of freshwater availability
in recent times, climate change
Problem statement
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In response to these and other challenges, water allocation planning now focuses more on optimizing use existing water resources. This is coupled with a shift away from the traditional emphasis on the construction of new infrastructure to meet rising demand, and instead to the adoption of demand management measures.
A major constraint for the preparation of environmental flow estimations has been lack of long-term flow data throughout the basin, which suggests that a risk-based approach to water allocation might be necessary.
A Sub Catchment Management Plan (SCMP) and Water Allocation Plan (WAP) have already been prepared for some sub-catchment of the Tana River. Other Sub-catchments are yet to be assessed to facilitate the preparation of the WAP. This project, which targets Thika sub-catchment, is designed for that purpose.
Problem statement
7
To determine; The status of WRUAs and other community-based groups working on water issues in the Thika sub-catchment and how they operate.
Appropriate principles and guidelines for WRUA’s planning and management.
Extent to which the WRUAs have implemented their plans.
Existing data that is available to inform water allocation planning in the sub-catchment.
Objectives of the scoping study
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The scoping study was designed to collect data through stakeholder interviews, desktop studies and other sources to review and document the status of Water Resources Users Associations (WRUAs) in the Thika sub-Catchment of Tana Basin.
The outcomes of the assessment will then be used as a baseline in designing the Water Allocation Plan of the Thika Sub-Catchment.
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Definitions1. Water allocation plan (WAP) -is a legal document that sets out the rules for managing the take and use of prescribed water resources to ensure resource sustainability. It is developed with the community, industry and key stakeholders for each water resource identified as being significant. It sets out how much water is available from a particular resource or area, how much water needs to be left in the system and what conditions will be applied to licenses in the local area.
Findings
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Equity: allocating water in a way that is fair and equitable amongst different users.
Environmental protection: enhances environmental flows and protects key freshwater services.
Development priorities: allocating water in a way that supports and promotes economic and social development
Balancing supply and demand Promoting efficient use of water
Objectives of a WAP
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There are six stages in the development of a WAP: A concept statement is developed that outlines the proposed content of the WAP.
The stakeholders are given an opportunities to help make decisions about the content of the concept statement.
Based on the decisions made about the concept statement, a draft WAP is prepared.
The stakeholders are again part of the decision making regarding the draft WAP.
Based on the decisions made about the draft WAP, a final WAP is then developed.
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The adopted WAP is reviewed within 10 years to ensure it still meet the needs of the environment and the community.
2. The sub-catchment Management Plan (SCMP) is a plan which is developed by WRUAs in collaboration with WRMA and other stakeholders. It reflects a set of activities designed to meet identified objectives to address the WRM problems within the sub-catchment.
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SCMP developmentSCMP
s poten
tial
SCMPs developed2011-2012 Cumulative
Catchment area No. No. % (dev-
potential)
No. % (dev-potential)
LVN 106 27 25 64 60LVS 137 7 5 19 14RV 32 58Athi 299 28 9 61 20Tana 254 11 4.3 57 22.4ENN 296 10 1 32 3Total 1530 104 7 234 15
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3. A Water Resources Users Association (WRUA) - is an association of water resource users, riparian land owners and other stakeholders who have formally and voluntarily associated for the purposes of cooperatively sharing a common water resource.Functions of a WRUA: Promote controlled and legal water use activities.
Promote good management practices to make efficient and sustainable use of the water resource.
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Promote water conservation practices to ensure sufficient water reserves that meet the demands of the environment, the wildlife, the livestock and all the communities who rely on the water resource.
To work towards reducing conflict in use of the water resource and participate in solving those that arise.
Promote catchment conservation measures to improve water quantities and quality.
Functions of a WRUA
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Leadership. Strong leaders are able to promote the WRUA both internally and externally.
Participation - need to understand and be willing to participate in catchment management at all levels.
Clarity of roles. Should have clearly defined roles and responsibilities
Autonomy - need the authority and ability to make independent decisions, collect and manage sufficient resources & resolve conflicts
Accountability& transparency - should be accountable and transparent to its members in all manner of its operation.
Characteristics of a Good WRUA
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Based on IWRM approach by WRMA, Thika River Basin has been delineated into 11 WRUA managed sub catchments
Out of this 11, there are seven operational WRUAs namely: Sasumua, Kiama, Thika Upper, Thika-mid, Thika Lower, Ekalakala and Lower Chania. The rest are proposed for operationalization and include; Mayambogo, Kabuku, Ngoliba and Maboko.
Following is a map of the sub-catchment;
Thika River sub-catchment WRUAs
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Each of these WRUAs covers an area over 100Km2. Sasumua, Thika-Mid, Lower Chania and Ekalakala WRUAs have developed their Sub-catchment management plan (SCMP).
Sasumua and Thika-Mid has shown progress in terms of implementing the plans.
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Riparian area conservation
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Tree nurseries establishment
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Felling eucalyptus tree along river line
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Tana and Athi Rivers Development Authority (TARDA),
Kenya Electricity Generating company (KenGen),
Nairobi Water and Sewerage Company,
National Irrigation Board, and Large scale firms such as Del Monte, Kakuzi, several flower farms and various other water service providers.
Major Stakeholders
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Mean annual rainfall: 200mm in Lower Tana – 2400mm in Upper Tana.
Total annual renewable water = 17529MCM/yr of which,
SW=5858MCM/yr (33%) and GW=11671MCM/yr(67%) Combined per capita water= 2540m3 which is more than the global benchmark of 1000m3. Thus the area has “moderate problems” as far water resources are concerned.
However, if only SW is considered, then the per capita water is 849m3 implying a chronic water scarcity.
Most people depend on SW including the major abstractor implying that water problems are driven more by SW and not GW
Water resources status
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Surface water GroundwaterCatchment area
Target Number
stations
collecting
data 4x/yr
% achiev
ed
Target Operational and
collection
data
% achiev
ed
LVN 36 17 47 14 14 100LVS 30 30 100 17 11 65RV 28 22 79 41 22 54Athi 31 0 0 24 0 0Tana 92 52 56.5 41 12 29ENN 40 ? 15 ?Total 165 69 42 111 47 42
Operational surface and ground water quality monitoring stations
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0
10
20
30
40
50 Maragua- Mean Discharge
4BE01_Maragua- Mean Discharge
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Water resourc
es
Total wetlands
identified
Target 2011 - 2012
Protecte
d before
2011
Protecte
d 2011
-2012
Total
protecte
d
Achievement
(%)
Wetlands 293 10 13 1 14 5Springs 349 11 15 8 23 6.5GW recharges areas
2 2 1 0 1 50
Riparian zones 1300 100 99 363 462 36Eroded and sensitive lands
296 10 13 1 14 5
Water resources protection
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Challenges faced in the sub -basinDeforestationEncroachment of riparian landSiltation of water bodiesWater scarcity Inadequate water infrastructureWater erosion and pollutionQuarryingRiver obstruction and illegal water
abstractions and over abstractionWater related conflicts
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Water obstruction
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Pollution
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Increased water conflicts due to obstruction or overabstraction
Reduced water levels and siltation of dams thus reduced water supply and storage
Increased soil erosion and landslides thus results in high costs of agricultural inputs or even death in case of landslides
Decline in aquatic life due to high pollution and sedimentation
Increased costs of water treatment and high incidences of waterborne diseases
Effects
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Water availability in the sub-catchments has been on the decline over the years. This has been caused primarily by unmatched population growth to the water available.
The increasing demand for water resources contributes to an increase in conflicts in water utilization due to competing interests.
Lessons learnt
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There has also been poor data collection due to low priority in data acquisition and management. Reliable data enables development of information needed for planning, development and management of water resources.
Environmental degradation has been increasing, the rivers are polluted and the dams are silting up very fast. High sediment loads of between 1,000 and 5,000t km-2 yr-1 have been documented at major gauging stations. This can be attributed to the changes in land use and land cover.
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No one-stop shop database of all stakeholders, activities done, achievements and challenges in TCA.
The WRUAs seem to concentrate more on livelihood projects other than their core function of protecting and conserving the catchment. These need to go hand-in- hand.
Capacity building for the WRUA members is not sufficient.
Geo-referenced database of all major water infrastructure in the catchment
Identification of gaps that need redress
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Ground water exploration and use has attracted little attention
Role of science and technology in water resources management is grossly underplayed.
Coordinated monitoring & evaluation –basin-wide and also carrying out an abstraction survey in the entire catchment
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Training and capacity building – this includes training on land and water use, basic practical conservation and management skills and also to facilitate exchange visits amongst stakeholders.
Installation of river gauging stations along all major rivers. This will enhance data collection and also help in monitoring and evaluation
Carry out an abstraction and pollution survey Community mobilization Identify a balance between WRUAs, county and National government
Strengthening links with research institutions and other stakeholders
Requirements for the next phase
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From the study much need to be done as far as water resources utilization and management is concerned.
Ground water has not been fully exploited…..SW and GW constitutes 33% and 67% respectively.
In upper Tana only 2 WRUAs have shown progress in SCMP implementation. One of which has done an abstraction survey.
Only one abstraction survey has been done that can be relied during WAP development
Conclusion
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1. Knoop L., Sambalino F., Steenbergen F., 2012. Securing Water and Land in the Tana Basin: a resource book for water managers and practitioners. The Netherlands: 3R water. Pp8-22.
2. Water Resources Management Authority, 2012. Strategic plan 2012-2017.
3. Sub –Catchment Management Plan for the WRUAs.
References
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WRUA field visit
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Thank you!