inventory, suitability assessment, and upscaling of best agricultural water management practices

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INVENTORY, SUITABILITY ASSESSMENT, AND UPSCALING OF
BEST AGRICULTURAL WATER MANAGEMENT PRACTICES

Makonnen Loulseged1, Seleshi Bekele Awulachew2, Gayathree Jayasinghe3, Fitsum Hagos4
and Teklu Erkossa5

1Water Resources Expert, 2Senior Researcher,3Biometrician, 4Economist, 5Agricultural/Irrigation
Engineer, International Water Management Institute (IWMI), East Africa and Nile Basin Office,
Addis Ababa, Ethiopia
[email protected]

Abstract Suitability of a technology in a particular
environment depends on many factors,
It is the belief of many analysts that such as, the nature of technical
agrarian countries like Ethiopia that complexity, the existing institutional and
depend on rain-fed agriculture are individual capacity to implement, the
significantly vulnerable to rainfall costs and benefits, etc. Technical
variability, the risk which tends to considerations include implementation
aggravate with global climate change. (set up), operation and maintenance,
Consequently, it is believed that future affordability and environmental impact.
increases in food supplies and economic The results of a ranking exercise of the
prosperity depend heavily on effective technical complexity of a given
agricultural water management. It is with technology are presented. Concerns
this in mind that the use of low-cost related to waterborne and water-related
technologies for rainwater and runoff diseases due to stagnation, water quality
control, storage, water lifting, and possibility of mosquito breeding are
conveyance and application have discussed.
become more widespread in Ethiopia Households in some parts of Ethiopia,
since the recent drought of 2002/2003. A who have practiced improved
range of technologies are currently used agricultural water management suitable
with varying levels of impacts. This to their local conditions, have managed
paper outlines an inventory, to diversify their incomes through
characterization, suitability and beekeeping, livestock, intercropping
upscaling aspects of Agricultural Water cash crops with food crops and setting
Management Technologies (AWMT) in up shops, hotels and flour mills in the
Ethiopia. Particular characteristics of nearby towns or villages. Therefore,
each of the technologies, their suitability AWMT at smallholder level meet the
for a given environment, and the intended purpose, provided that they are
necessary conditions for their successful suitable and adaptable to the local
adoption and scaling up are identified. circumstances. The question is which of
Furthermore, a variety of combinations the technologies are suitable to which
of technologies used for control or area under what socioeconomic
storage, lifting, conveyance and conditions?
application of rainwater are documented.
153
limited possibility to diversify
agricultural production, underdeveloped
Introduction infrastructure, and weak or sometimes
lack of access to agricultural markets
Ethiopia covers a land area of 1.13 and to technological innovations (S.B
million km2, with a population of 77 Awlachew et al., 2005). As a
million at 2007 estimate. The consequence the rural dwellers in the
physiographic is characterized by country are among the most vulnerable
complex highland mountains and to poverty as they entirely depend on
plateaus. The agricultural potential is agriculture for their livelihood. The
largely unexploited; with less than 40% agriculture sector is highly dependant on
of the arable land currently under rainfall, thus the amount and temporal
cultivation. Rainfall is generally greatest distribution of rainfall and other climatic
(around 2200 mm per annum) in the factors during the growing season have
southwest highlands and decreases to an important influence on crop yields.
around 600 mm per annum in parts of When rainfall variability increased
the northeastern highlands. Much of the across the country, average food
rainfall in the country occurs between production per capita has also declined
June and September only in the southern in the past years, and the country has
and eastern highlands, there are become increasingly dependent on
pronounced bimodal rains with the first imported food. Presentation made on
peak in April and the second in Impact of Irrigation on Poverty and
September. Rainfall variability generally Environment (IIPE) Symposium (S.B.
increases as rainfall itself decreases and Awlachew, 2007) confirms that the
is thus generally greatest in the lower performance of Ethiopian economy is
rainfall areas of the north and northeast directly linked to rainfall variability
highlands. The mean daily temperature (Figure 1). It is estimated that in
in the highlands during the growing Ethiopia, one drought event in 12 years
season (May to December) is 21.3oC, lowers GDP by 7 to 10% and increases
and drops by 0.6oC for each 100 meters poverty by 12 to 14 percent. This calls
increase in altitude (Goebel, 1983). for use of effective and efficient
agricultural water management
The cultivable land is about 13.2 million technologies to mitigate its negative
ha, or 12% of the total land area (FAO, impacts. At the same time, the country is
1998). But agricultural productivity endowed with surface and ground water
remains very low partly due to limited that can be used for boosting agricultural
access to agricultural technologies, production sustainable.

154
Irrigation/AWM is Important in Ethiopia small scale irrigation (S.B. Awulachew
et.al, 2005) and the traditional irrigation
• To overcome long dry spells (leading to crop failures) and estimate is about 13,820 ha. However, if
drought (3 major droughts in 30 years)
it were not because of lack of proper
Impact of rainfall variability on GDP and
Agricultural GDP growth inventory, the total area irrigated using
80 25
modern and traditional methods exceeds
60 20
15
40 10 this amount.
20 5
0
% 0
-201982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000--150 Recently, rainwater harvesting and use
-40 -15
rainfall variability -20 for agricultural production has become
-60 GDP growth -25
-80 Ag GDP growth -30 common to many areas. Harvesting
year
-The impact of costs 1/3rd of growth potential of Ethiopian economy runoff during the rainy season can
-GDP Growth: 2002/3 GDP was -3.3%; 2004/5 was 11.9%; 2005/6 was 10.6%
November 27-29, 2007, Addis Ababa, Eth(cid:206)iop6ia.4% average growth supplement irrigation development and
fill the gap during the drought season in
Figure 1: IIPE Symposium presentation, rain fed agriculture. Massive program
S.B. Awlachew (2007) was planned by the government during
the period 2001 to 2005 and
Water resources and AWMT implemented by individual households.
Farmers have continued adopting these
The country is faced with a rapidly technologies and have continued
growing population and an agricultural benefiting in areas where it has become
production which in most years, falls successful. The use and adoption level of
short of the food requirements mainly the different types of technologies
because of rainfall variability. The total differs from place to place. However,
mean annual flow from all the river water management efficiency and
basins is estimated at 123 BMC. Only production level of agricultural outputs
about 200,000 ha has been developed has remained a question in many of the
using irrigation and yet more land has to places even in areas where there is
come under irrigation to feed the fast successful adoption.
growing population and combat the
effect of drought. Different types of Objectives
irrigation have been used in different
parts country, ranging from small scale The overall objective of the AWMT
traditional methods to large-scale project is to contribute to improving the
commercial farms. lives of rural poor through improved and
There are twelve river basins twenty lake sustainable agricultural productivity and
bodies, four crater lakes and over twelve generation of incomes for smallholder
major swamps or wetlands. Irrigation in farmers in Ethiopia. Specifically, this
Ethiopia is classified as large with a study aims at assessing suitability of
command area greater than 3000 ha, AWMT and identification of promising
medium with a command are between technologies for scaling up.
200 and 3000 ha; small scale with a
command area less than 200 ha. The Methodology
small scale irrigation (SSI) schemes are
managed by the community. The The method of collecting data and
estimated 48,000 ha is under modern information included literature review
155
from both local and international Ethiopia. Therefore, the first part of this
sources, key informants interviews and study “identification and
discussions at all levels including characterization of AWMT” is the first
federal, regional and in some instances of its kind in documenting a wide range
at zonal and woreda levels. In addition, a technologies all together in one. More
questionnaire was designed and than 50 agricultural water management
distributed to relevant experts in various technologies practiced in Ethiopia were
institutions (GO, NGO, UN agencies, identified through the inventories. The
private, etc) to capture diversified information made available through this
information on agricultural water study can serve as a reference for further
management practices, ranking of investigations. Annex 2 provides
technologies and suitability including the summary of these technologies, their
constraints that exist (Annex 1). Where advantages and constraints in brief.
conditions favor site observations were Rainwater harvesting for crop
made and discussion with individual production, if successfully implemented
farmers were also held. within a social and hydrological
catchment, will have many interacting
Limitations implications on biophysical, economic,
and ecological systems, suggesting that a
This study was based on a one time field systems approach needs to be considered
visit to regional capital of Amhara, when promoting Rain Water Harvesting
SNNP, Tigray and Eastern and Western (RWH) (Rockstrom, 2000). Water
Hararghe zones of Oromia regional state harvesting structures built without
where most agricultural water consideration of the whole catchment
management technologies are practiced. have faced serious problems like
Few promising technologies were also siltation, water shortage, conflict of
visited during the field trip. In view of interest, etc. The suitability of AWMT
the broad scope of the study, which depends very much on the specific
covers the entire country and the environment and local conditions of a
diversity of technologies, the time particular area. Some of the conditions
allocated to the project was not broadly include agro-ecology,
adequate. In addition, farmer’s infrastructure, socioeconomic conditions
involvement in the study was not (market, cultural, etc).
adequate. However, the information
through the various tools is believed While altitude, temperature and rainfall
adequate to present the general overview determine the range of cropping
of agricultural water management possibilities, the actual patterns of
technologies in Ethiopia. cropping that predominate are
determined primarily by the lengths of
growing periods and by socio-economic
Depending on the topography, agro- considerations. Other physical
climatic conditions and the farming conditions such as soils are also
systems, different types of AWMT are important in influencing potential for
used in different parts of Ethiopia. There plant growth. Crop management
has been no exhaustive inventory of practices such as cropping systems,
modern as well as traditional AWMT in fertilizer, and weed and pest control also
156
determine the efficiency of agricultural symposium and other sources of
water use. Intercropping cash crops with information, it has become clear that
food crops is practiced in some areas to some technologies are working very well
maximize the production from a limited in some parts of the country and fail in
farm size of a water harvesting structure others. Annex 5 presents the location of
and may ultimately contribute to the these technologies where they are widely
success of the technology. In adopted and practiced.
consideration of the above, the high and
low potential cereal zones and high Conditions of suitability for agricultural
potential perennial crop zones have been water management technologies
classified by Ethiopian Highland
Reclamation Study as shown in Annex The appropriateness micro-catchments
3. to specific agro-ecological conditions is
crucial to the success of technological
One of the main constraints in the interventions. In drought-prone semi-
scaling up of any conservation measures arid areas, the introduction of rainwater
is non ownership of asset by farmers. harvesting is generally successeful,
Livelihood is a pressing day to day although fluctuation in the amount of
question to farmers and as a result rainfall remains to be a major constraint.
farmers often fail to focus on long term For example, half moon is implemented
objectives but rather they need early in areas receiving rainfall less than 500
return to any investment. As a result, mm. It is suitable in areas with sandy
interventions with long term gestation and sandy loamy soils affected by low
period are not generally favored by fertility levels and thin surface crusts
farmers. The dwindling land holding size that inhibit infiltration and increase
of farmers where they can not afford to runoff. On the other hand, Fanya Juu is
allocate portion of their plot to be used well adapted in areas where the rainfall
for conservation structures is also ranges between 500 to 1400mm. It is
another bottleneck to scaling up of widely practiced in Dega, Woina Dega
agricultural water management agro-climatic zones, dominated by
technologies. heavy soils and where erosion problem
is critical.
Technology suits in practice
The suitability of technologies depends
There are different combinations of also on the specific site conditions, such
technologies that are used from the as slope, soil depth, cropping pattern,
source up to delivery of water to crops. erosion level, etc. According to L.
Affordability, experience, availability, Desta, et al., 2005, the measures listed
lack of awareness is among the factors from Annex 6 to 9 are broad indications
that influence these combinations. The of suitability of soil and water
commonly adapted combination of conservation interventions based on
agricultural water management suits are agro-climatic conditions and land use.
shown in Annex 4. However, the For example in cultivated land and
choice, adoption, suitability and success homestead areas, measures like soil
of AWM technologies were not clear. bunds, stone bund, fanya juu, BBF, etc.
Out of the results of the 2006 are appropriate. Flood control and
157
drainage measures like vegetative or watershed and linkages between the agro
stone paved waterways are suitable for ecological system and rural society, and
grazing lands. Stone faced soil bunds between production and marketing,
and cut off drains are more suitable for among others (Stephen N. Ngigi, et. al
forest areas with steep slopes where as 2003).
level bunds are better suited in gently Rainwater harvesting techniques can be
sloping and moderately sloping areas. In applicable in all agro climatic zones.
general, conservation technologies are However, it is more suitable in arid and
varied and their appropriateness is agro- semi arid areas. These are areas of
ecology based and purpose oriented. average annual rainfall <800mm (rarely
exceeding 800mm). Rain may not come
Open ponds are suitable where unskilled on time and in such environment, rain
labor is abundantly available, fed crop production usually needs to be
evaporation loss is relatively low, when supplemented with rainwater harvesting.
efficient water conveyance and
application technologies are used, when According to Oweis T., D. Prinz and A.
there is limited capital to invest but, Hachum. 2001, generally water
unsuitable where there is severe shortage harvesting is advantageous in the
of land and where favorable conditions following circumstances:
exist for malaria proliferation. • In dry environment, where low and
Underground cisterns are suitable where poorly distributed rainfall normally
skilled labor is available, evaporation makes agriculture production
and seepage loss is relatively high, there impossible
is severe water scarcity, when higher
• In rainfed areas, where crops can be
water quality is required and in areas of
produced but with low yields and a
free grazing.
high risk of failure. Here, water

harvesting systems can provide
In situ technologies are most suited to
enough water to supplement rainfall
conserve soil, water and increase
and increase and stabilize
vegetation cover and when there is a
production.
need to increase ground water recharge
• In areas where water supply for
for shallow well exploitation. Shallow
domestic and animal production is
ground water and spring development
not sufficient
are suitable when good quality and
dependable source of water is required. • In arid areas suffering from
Shallow well is less functional in loose desertification, where the potential
soils due to likely construction for production is diminishing, due to
difficulties. lack of proper management.
Practitioners agree that if technologies Providing water to these lands
are to become successful series of chain through water harvesting can
of measures are required. Production of improve the vegetative cover and can
crops have to be linked to cooperatives, help to halt environmental
this in turn linked to processing plants, degradation.
again linked to market, etc. A system In country experiences and lessons
approach would involve different drawn from other countries indicate that
biophysical disciplines within a adoption of new technology becomes
158
more effective if supported by applied and has been integrated into the
research and demonstration sites. questionnaire to get experts feed back.
Furthermore, a guideline shown in The summary of the performance of
Annex 7 can be used for selecting water technologies as per the feed back
harvesting techniques depending on the obtained from four regions has been
soil type, topography, land cover and presented in Annex 10.
other socio-economic considerations
(Oweis, T., D. Prinz and A. Hachum, Promising technologies
2001). Earlier inventories carried out by
The performance of technologies in different institutions for different
terms of implementation, operation and purposes provide indicative information
maintenance, affordability, gender on the type of technologies used and the
sensitivity, environmental impact, etc., level of their utilization. Tables 1 below
has also been assessed through a indicate the type of technologies and
questionnaire. Suitability depends on the extent of their adoptability and usage in
nature of technical complexity, the three regions. In SNNPR, based on the
existing institutional and individual available information almost all small
capacity, the investment capital and scale irrigation development comes from
operation and maintenance cost, and river diversion.
benefit. Therefore an elaborated
suitability criteria has been developed,

Table 4: Commonly practiced AWM technologies in Amhara Region
Technologies Amhara Region Oromia Region irrigation Tigray Region
coverage (%) coverage by water source coverage (%)
(%)
River diversion 95 69 75
Micro dam 0.1 6
Pump 1.1
Hand dug shallow well 3.5 12.7
Deep wells 0.2
Pond 0.3 2 6.03
Spring development 21
Spate irrigation 0.07
Lake 8
Total 100 100 100
Source BoWR, Amhara; Based on Water Resources Evaluation of water
Regional Irrigation Land and Irrigation harvesting schemes
and Water Resources Development in Ethiopia, in Tigray, 2004
Inventory, 2005 2007

all the regions visited. Shallow wells and
From Table above, it is evident that river spring development are attractive for
diversion plays a critical role in the household level agricultural
development of SSI followed by shallow development. In areas where shallow
wells. River diversion is widely used in ground water potential exists it is
159
exploited by communities. Water Table 5: High ranking promising
pumping, farm ponds, deep well technologies
exploitation are relatively new
technologies and hence were not widely
Source Technology
used among communities in the past.
Water harvesting Trapezoidal pond,
Micro dams are more important in areas
Ground water Hand dug shallow well
where there are less perennial rivers and
Spring development
river flows run during few months of the
Runoff diversion Spate irrigation
year. It is mostly practiced in the
River diversion Upgraded traditional irrigation
northern regions of Ethiopia.
system
Annex 11 to 14 elaborates details of the
Modern irrigation system
ranking exercise; technical performance
Water lifting Treadle pump
such as easiness of implementation, skill
technologies
manpower requirement, financial
Small motorized pump
requirement, etc of micro catchment

RWH structures and groundwater

exploitation; water lifting and water
The result is reasonably in line with the
application technologies; and micro
outcomes of the discussion made with
catchment technologies respectively.
key informants in the four regions. It
The technologies adopted by the regions
was observed that promising
were also ranked in terms of their
technologies identified by experts in the
technical complexity and financial
respective regions (Table 3) are adopted
requirement for implementation; the
by farmers in a greater scale because of
result is summarized (Table 2).
their suitability to the local conditions
Accordingly, trapezoidal pond, hand
i.e. addressing farmer’s needs, capacities
dug shallow well and spring
and the service that are realistically
development ranked better among water
available. As indicated in the ranking
harvesting and ground water exploitation
exercise these technologies are found to
technologies. The most promising SSI
be technically simple to set up, operate
technologies are runoff diversion (spate
and maintain; low investment, operation
irrigation), upgraded traditional

irrigation and river diversions when site
and maintenance costs compared to
conditions are favorable with out
other technologies. Conservation
considering the cost–benefit analysis.
activities are considered as
This can also been witnessed from the
complementary to ex-situ activities and
extent at which they are used in the
therefore, they are not considered in the
different regions of the country. Among
prioritization. It was observed that
the few water lifting technologies
institutions particularly NGOs through
practiced in the country; treadle pump
their long experience have specific
and motorized pump (small) are the most
technologies to promote in their program
preferred ones based on technical and
area. However, there is a general
capital considerations. Although not
consensus that upgrading traditional
widely practiced the limited information
irrigation schemes, shallow well
obtained show that wind mill is less
development and runoff diversion (spate
complex to use where potentials exist.
irrigation), and river diversion are the

most promising technologies, and hence
160
can be considered for scaling up
depending on the specific conditions of
the respective region (Table 3).

Table 6: Most promising technologies by Region
Region Technology Justification
Amhara Upgrading traditional high level of ownership feeling as they are originally built by the farmers
schemes themselves, better operation and maintenance or scheme management; improving
from spring/ river structures and make them permanent; high discharge with large command area
and hence benefits many farmers
Shallow well development where shallow ground water is available provides reliable water; good water
quality may have multiple uses including domestic water supply
Water harvesting Trapezoidal ponds in suitable agro-ecology with evaporation mitigation measure
and availability of market
Oromia Upgraded traditional Shortage of water source could occur and u/s-d/s conflict might be created;
irrigation established farmers organizations and working procedure;
Shallow well Where opportunities exist they are reliable source of water; could be easily
constructed with locally available material; can be managed by individual
households.
Runoff diversion/ In low land semi arid areas traditional runoff harvesting can be done with farmers
spate irrigation knowledge and labor

SNNPR Upgraded traditional Because of simplicity in operation and maintenance; low cost ; farmers have long
irrigation from river irrigation experience
Shallow well In high land agro-ecological zones, high value horticultural crops in homestead
areas can be grown. At house hold level where potential exist shallow wells,
spring development have priority over other technologies.
Water harvesting structures Can be constructed with family labor,
(Ponds)

Tigray Modern river diversion • It can irrigate large area and easy to manage
• No sedimentation problem unlike dams except in canals

Micro dam • Stores water during wet season including from non perennial rivers to supply
water during long dry season
• It has a capacity to hold larger amount of water
Shallow well • It is possible to irrigate using shallow well during dry season
• It provides irrigation water sustainable during dry season unlike other
technologies

Some case studies
The impact of these technologies on Small Scale Irrigation
poverty alleviation; the cost and benefit The topographic map developed by the
has been analyzed (Fitsum Hagos et.al. Ethiopian Mapping Authority (1:50,000)
2008), but the results are reported is far less than sufficient for assessment
separately. of SSI potential in the country. A more
accurate assessment tool needs to be
161