Integrated Rainwater Management Strategies in the Blue Nile Basin of the Ethiopian Highlands

Water for a food-secure world

Integrated Rainwater Management Strategies in the Blue Nile Basin of the

Ethiopian Highlands

Birhanu Zemadim, Matthew McCartney, Simon Langan and Bharat Sharma

International Water Management Institute

Water for a food-secure worldWater for a food-secure world

Background

Ethiopian highlands of the Blue Nile Basin;

– Have enormous agricultural and natural resources potential – Mean annual rainfall 900-2500mm

• Is not easily retained in the form of surface/ground water• Much of the water is lost to runoff

– Majority of people are rain-dependant– Fragile landscapes

• Poverty and marginalization of the rural villagers


Common Problems and Results • Land degradation and water scarcity• Poor land management practices and lack of focus on Rain water management Strategies (RWS)

i. Existing structures to harvest rainwater were not built to the required standard,

ii. Structures cannot contain enough water,iii. No close supervision of the structures,iv. The approaches lack community cooperation,v. Most structures were built rapidly with poor planning and lack

of decentralized ownership systems

• Hardship and insecurity – Inability to safeguard livelihood systems

• The vicious cycle of poverty is aggravated

Results of poor RMS to the local community


Major goal of RMS

• Improving the resilience of rural communities,

• Contributing to poverty reduction,o Improve the quality of life of rural communities

• The goal is achieved through natural resources regeneration and management (watershed approach)o Restoration of the local environment through RW Harvesting (RWH) o Focus on the entire watershed and integrated community-led approaches

• Need to have an environmental unit for planning and implementation


Existing Practices of RMS in Ethiopia

• Traditional RWH techniques, – Runoff farming closely related to Soil Water Conservation (SWC)– Dated back to 1970– Targets reducing soil erosion with little or no interest in enhancing soil water infiltration

• In-situ water harvesting techniques, micro-basins

• From 40,000 RWH ponds constructed between 2003 and 2008 in Amhara and Tigray region of Ethiopia, most have failed (AMU, 2009),

• Slow uptake by local farmers,

• The technologies are rarely sufficiently adapted to local conditions,


One of failed rainwater harvesting structure in in FOGERA district

Non functional hand pump in MADAJALALA AREA, DIGA district, EAST WOLLEGA

Flooding in FOGERA district

Status of Existing Structures and natural phenomenon

Water fetching in Mizewa highland


Existing Practices of RMS in Ethiopia

• Protecting forested areas and reducing soil erosion by building terraces and planting tree seedlings since the mid-1970so Resulted in limited success (Bishaw, 2001)

• Emerging successful stories of RMS programs in Ethiopia:o As part of Sustainable Land Management (SLM) project by MoARD,

Projects are showcased in Amhara, Oromiya, Tigray and Somali region include various technologies and approaches to increase in-situ water availability and increase aquifer recharge


Towards effective RMS….. Lessons learnt

o the full range of water storage options in catchments need to be considered. These are water storage in:

soil moisture, wetlands, water harvesting structures and groundwater

• Are best achieved on a micro-catchment basis-environmental unit

• The approach emphasizes self-help, ecological regeneration and “catching rain wherever it falls”

• The principle addresses the need to work on different water storages options


Conceptualization of the physical water storage continuum

after McCartney and Smakhtin, 2010


Planting trees and grasses to stabilize waterways and provide fodder and fuel wood

Instituting bans on tree felling and grazing for natural regeneration of shrubs and grasses

Training villagers in new or improved agricultural practices and livelihood activities

Supporting cottage industries and supplemental income generation through micro-lending schemes


RMS through watershed development approach:- hydraulic structures & management

• Three basic operations– Area Treatments– Drainage Line

Treatments– Afforestation and

pasture development

• The operations need to be conducted from ridge to valley at a watershed level


Continuous Contour Trenches (CCT) or hillside terraces

• The technology avoids the use of stones in farmlands and has got positive perception of its usefulness and active promotion by extension service in Ethiopia (SLMP, 2010).

CCT / Hill side trenches

Area Treatments

• Has its origin in India and has been practiced in Blue

Nile basin, Tigray region, North Shoa and Awash basin (SLMP, 2010)• Result in control of erosion, retention of soil fertility, better soil moisture regime, infiltration and ground water recharge

• Are practiced in low to high rainfall (250-3000mm) regimes, and mild to steeper slopes (5 to greater than 60% slopes)


Stone/Soil bunds

Stone Bunds across the slope

• Is widely adopted by many farmers in Ethiopia to retain rainwater that becomes runoff and later causes erosion

• Is essentially a water harvesting practice intended to store rainwater for crop production and enhance ground water recharge

• Arrest the flow of water and control erosion in areas where soil work is not possible

The technology has been practiced in Blue Nile basin, Tigray region, North Shoa and Awash basin (SLMP, 2010)


Vegetation bunds and plantation along CCTs

Vegetation Bunds and plantations along CCTs

Photo from INDIA

• Are practiced in high rainfall regimes and steeper slopes to reduce the effect of flood problems

• Found to be suitable to steeper areas receiving high rainfall

• to enhance moisture and water harvesting,

• increase biomass, conserve water and control erosion.

• Effective soil erosion control and prevention of gully erosion (SLMP, 2010)


Biophysical measures integrated with area enclosures

• Are common practices to help maintain the productivity of degraded land which has been abandoned

• Unproductive and waste lands are changed to productive land by the prevention and reduction of erosion and enhance land rehabilitation (SLMP, 2010).

Paved and grassed water way technology


Drainage Line Treatments

Begin from the top of the watershed

• Series of gully plugs and earthen and stone dams

• Check dams and percolation tanks

Gully plugs along drainage line


Agro-forestry system and Pasture development

• Include growing of various crops (perennial trees and shrubs with annual crops)

o Meet household needs of fruits, fuel, fodder, timber and fibero Add organic matter to the soilo Control erosiono Slow runoff and accelerate infiltrationo Higher income and less biotic pressure on grazing grounds


as part of Integrated RMS …

Biophysical Research

Monitoring and Modeling


Watershed approach towards effective RMS …..


Research SitesIn areas (called “study landscapes”) representing dominant

agro-ecological zones and farming systems

Fogera: a relatively high potential, market-oriented, rice–based system);

Jeldu; a relatively low-potential system with steep agro-ecological gradients

Diga/Dapo: a relatively high potential system with poor market access but with high value crops and livestock potential

Water for a food-secure world

A Participatory Approach for Hydro-meteorological Monitoring


Monitoring provides biophysical information that can be used to evaluate the impacts of RMS on hydrological flows as well as to determine water-use and water productivity in different landscape components


Example of natural variability in rainfall and flow, in Fogera District (Data from 1992-2003)

From May to October average rainfall record > 50 mm

Long-term MAR is 1330 and 511 Mm3 for Gumara and Ribb

Total flow volume of 1841 Mm3


• Average per capita water availability is 2595 m3 per year– A figure higher than both the national figure (1707 m3) and

basin figure (2029 m3).

• Heavy floods in the rainy season are typically followed by water shortages during the dry season

• Much of the available water in the area remains unutilized


Case study Mizewa watershed: Flooding

Photo taken in August 2012


Case study Mizewa watershed: Drought

Photo taken in March 2013


Dry season water search in FogeraFebruary to May


Establishment of 3 watershed monitoring networks in the Blue Nile Basin of Ethiopian highlands


Monitoring Locations

Dapo watershed 18 km2

Mizewa watershed 27 km2

Meja watershed 96 km2


Methodology

• A participatory approach involving local community and other stakeholders

• A scientific approach -the application of scientific and engineering principles in design, construction and installation of the component structures

• Activities undertaken– inception of idea/stakeholder identification – designing the network – installing the network – monitoring and maintaining the network – collating, quality control and data archiving– communication and feedback mechanisms


Community consultation Community engagement in installation of soil moisture and ground water level devices

Monitoring Soil moisture and ground water levelWeather station installation


Challenges

Vandalism • This relates primarily to the automatic flow

gauging stations, located on road bridges at the outlet of each watershed

Flood damage


Flood damage


Main outcomes of a participatory approach conducted in the three watersheds:

– identifications of appropriate sites for hydrologic monitoring

– reduction of costs of installation and maintenance

– provision of security to the installed network

– instilling a sense of ownership within the local communities


Biophysical data monitoring for improved decisions making

Full scale, high resolution hydro-meteorological monitoring will improve decisions towards appropriate rainwater management strategies (RMS) and hence livelihood improvement

Appropriate basin wide decision support tools based on hydrological and agro-ecological systems is required to prioritize sustainable RMS, and study downstream impacts and eco-system services


Watershed Management Practices

and Hydrological Modeling……………..

Technology

Integrated Rainwater Management Strategies in the Blue Nile Basin of the Ethiopian Highlands