Michael WatersProject Manager

SMEC International

NairobiNairobifor Ministry of

Regional Development Authorities

SUSTAINABLE HYDROPOWER IN KENYA:

CASE STUDY –CASE STUDY –The Magwagwa Multipurpose Dam

Development Project

Outline for presentation

Feasibility

Project Components

INTRODUCTION

Feasibility Assessment of

the projectEnvironment

and social sustainability

CONCLUSIONS

IntroductionIntroductionIntroductionIntroduction

Project location

Proposed irrigation

area

Dam site location

Project Project Project Project componentscomponents

Project Components DHWIFFCTER

� Dam � Flood Management

� Hydropower � Catchment � Hydropower � Catchment management

� Water supply � Tourism development

� Irrigation � Environmental & social impact assessment

� Fisheries development

� Resettlement

Dam, Hydropower, Irrigation

• Previous Feasibility study conducted by JICA in 1991

• Dam: 110 m high, CFRD, 4.3 Mm3 volume

• Hydropower: 120 MW HP capacity, peaking • Hydropower: 120 MW HP capacity, peaking operation, for 8 hrs/day supply (357 GWh/yr)

• Irrigation: 15,000 Ha in the Kano Plains Area, mostly for rice production

• IRR 7.7% (HP only)

• Current study: can additional benefits can be identified?

Water supply

• Kenya experiences water scarcity

• Annual fresh water supply 647m3/person

against int’l stds 1000m3/person against int’l stds 1000m3/person

• 44% of locals surveyed have no access to good quality domestic water

• Population of 600,000+ persons to benefit

Fisheries, Flood; Catchment and Env. Management

Integrated approach proposed

a) Reservoir Fisheries

b) Catchment wide initiative-10,000ha

c) 70 km biodiversity corridor along the c) 70 km biodiversity corridor along the riverine

d) Sustainable land practices within 100m of the riverine corridor

e) Robust Environmental Management and Monitoring Plan

Tourism Development

The Magwagwa Area is endowed with range of scenic landscapes and good climate year round

Feasibility assessmentFeasibility assessmentFeasibility assessmentFeasibility assessment

Topography; Hydrology and Geotechnical investigations

• Assessed for the dam/reservoir area; irrigation canal alignment; power and water supply transmission line.

• Rainfall and landform data collected for • Rainfall and landform data collected for hydrological assessment

• Context suitable for dam and hydro plant construction

cont

Mean Annual Flow 40 m3/s

Catchment yield 1.1mm/d

b) Assessment of Engineering options

Dam and Hydropower

Water supply

Irrigation

The Dam

Dam

Dam typeDam site

and heightDam typeFour dam types assessed based

on the topography and

the geology of the proposed dam sites i.e. CFRD; CCRD;

AFRD & RCCD

Location of dam axis

Seven potential dam axes evaluated in the Sondu gorge

in the vicinity of the proposed dam site

and height

Four dam sites with varying dam heights assessed to evaluate

construction cost ; power output; socio-economic

implications; and the

flood routing capacity

Preferred options for the dam/reservoir

• Max. height of the dam 95m

• Dam Type-Concrate Faced Rock fill Dam

• Location-River gorge 2 km East of • Location-River gorge 2 km East of Magwagwa town

• Crest level-El 1655m ASL; reduces inundated area from initial 25km2 by JICA to 17.7km2

• Maximum Storage of reservoir 485 MCM

Preferred hydropower development

• Underground waterway of 15.5 km in length (was 9 km with JICA)

• Power station equipped with two 57.7 MW Francis turbines; total plant rating of Francis turbines; total plant rating of 115 MW

• Supply base power ~ 600 GWH/year (357 GWh/yr JICA)

• IRR: 12% (7.7% JICA)

Water Supply

�Demand is clustered into three main service areas (brown, red, blue)

�Brown has best feasibility �Brown has best feasibility (gravity only)

�Red and Green require pumping –marginal feasibility

Irrigation

�Area proposed for irrigation 13,807ha

�Reduced �Reduced dependence on rice (low value crop)

Fisheries development

-Cage culture and capture fisheries proposed

-100 cages to be -100 cages to be established

-25metric tones

of fish per

Season/cage

Tourism Development Components

Environmental & Environmental & Environmental & Environmental & Social SustainabilitySocial Sustainability

Catchment conservation

Env. Management

Potential Impacts Mitigation measures

Alteration of the flow regime Establishment of a natural flow

regime/maintaining environmental flows in

the depleted area

Diversion of water, creating a Ensure an acceptable minimum flow is Diversion of water, creating a

depletion zone downstream

of the reservoir

Ensure an acceptable minimum flow is

maintained in the depleted zone.

Inundation of the reservoir

area

Creation of a buffer zone around the

reservoir

Management of ecologically

sensitive sites

Creation of a voluntary riverine

biodiversity corridor

displacement of persons. -Resettlement Plan

-public consultation

Inundation of major roads Rerouting of roads, creation of new roads,

upgrading existing roads

Resettlement

• 18km2 of land to be inundated

o Transmission line and water wayleave-510 acres

o Involuntary resettlement of 838 o Involuntary resettlement of 838 households

• Resettlement Plan developed:- Land acquisition, forms of compensation and relocation preferences

Resettlement Cont…

• Major assets for compensation

a) Private houses and sanitary facilities

b) Farm land

c) Private plantationc) Private plantation

d) Grazing land

e) Public buildings and temporary losses to social services infrastructure

Conclusions

MMDDP can be feasibly developed as a sustainable multipurpose water resources development project

The project relies heavily on hydropower to The project relies heavily on hydropower to ensure overall economic feasibility

Social and environmental benefits through irrigation, water supply, fisheries, catchment management and tourism developments

END

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