Transcript The role of indigenous knowledge in determining design and

The role of indigenous
knowledge in determining design
and the planning of water
harvesting systems
Amanda Coffey
Water Resources
In this presentation…..
• The role of indigenous knowledge for water harvesting is
crucial to project design
• through participatory approaches and innovative
dialogue
• Brief overview of indigenous practices & their breakdown
• Focus on Sub-Saharan Africa & its role in development
Traditions in water harvesting
• The Negev microcatchment techniques. Socio-political
changes led to a decline of sedentary agriculture from 7th
Century
• The meskat system in Tunisia is still in widespread use,
but there’s some decline recently due to labour
shortages or migration
• Wadi flow harvesting in the Middle East & North Africa is
generally abandoned & neglected now
• Iraq, Iran & Arabian peninsular – quanat/ falaj systems
still in use but under threat from tube wells
• In Latin America, terracing & conduit systems
existed e.g. Peru. The largest loss of WH systems is
here due to the Spanish conquest
• In N America spate farming by the Papago & Navajo
Indians was decimated by the arrival of Europeans. It
is still practiced.
• Sri Lanka has a long tradition of water harvesting for
domestic drinking water supply. Commonplace until
the 1950s when tube wells & piped water were
introduced. Now a revival through government
initiative: Community Water Supply & Sanitation
project
In India, Sri Lanka & Pakistan runoff farming has been
developed extensively in the khadin system
• The practice of using tanks as runoff storage is still
widespread, but in decline. Problems associated with a
relaxation of feudal landlord-peasant farmer relationships
leading to land degradation & increased silting
• A kund in the Thar Desert, India. A covered underground tank to
harvest and store rainwater
Areas with runoff agriculture or the potential for
runoff agriculture (Barrow 1999)
Areas with runoff agriculture or the potential for
runoff agriculture (Barrow 1999)
Focus on Africa
• Water harvesting traditions are widespread in Africa e.g.:
• Zai & tassa planting pits in Burkina Faso, Mali, Niger
• Earth bunds are used in the meskat system in Tunisia,
trus system in Sudan & caag & toog system in Somalia
to capture overland flow & gully flow
• Flood water harvesting & spreading wadi flow, Sudan
• Foggara (falaj/ quanat) well systems for shallow
underground runoff
• Sudan probably has the most extensive and diverse
heritage
Water Harvesting in the Red Sea
Hills, NE Sudan
• Mountainous, hilly terrain with wadis
• The Beja are the dominant social group
depending on pastoral transhumance & farming
• Domestic water supply is from hand dug wells
• Irrigation is supplied by building earth
embankments across wadis to spread the water
outwards
• Large crescent shaped bunds are built on the
wadi beds & planted with sorghum
Low lying crescent embankments
capture water spread from wadis
• Without this indigenous technique of water harvesting life
here would be impossible
• In the 1950s a diversion dam was built at El Garad. Now
it’s miles away from the wadi!
• Technical solutions aren’t guaranteed!
• The Beja developed this technique that is flexible, & fits
in with labour requirements & social structure
• It forms the core of a government programme
(SCLUPWA) initiated in 1986 to expand into new areas
and increase sorghum production for household
consumption & cash sales
The role of trus cultivation in Darfur,
eastern Sudan
•
•
•
•
•
•
In Central Darfur pressures include:
climate change,
increasing drought risk,
huge population growth,
changing social structure,
loss of common land & tenure
• And there’s a potential conflict between traditional
techniques & modern water harvesting techniques
The revival of trus cultivation
• After the 1983-85 drought the population doubled due to
migrants from other drought areas & this led to the trus
system being revived
• A tera is a U-shaped low earth bund 35-40cm in height is
constructed facing the slope. A typical plot is 3 ha. The
catchment is 2-3 times this
• The system is flexible with social, economic &
environmental changes and sustainable
• In recent years urban farmers & merchants have begun
water-spreading projects using machinery to construct
earth embankments across wadis. They require high
capital inputs
The traditional trus cultivation
Water spreading from a wadi
Private gain or common interests?
• Crop yields are greatly improved yielding 650kg/ha
compared to 150-250 kg/ha under rainfed agriculture
• Commercialisation of modern water spreading
techniques is resulting in farm sizes of 50-200ha,
compared with 2-5 ha for a subsistence farmer
• This may lead to shortages of staples, as vegetables are
grown for urban markets
• The construction of permanent structures clashes with
traditional land tenure system
• Communities down stream may suffer reduced flows
• ITDG are working to support communities. The process
must be carefully managed to maintain the balance
Is there a conflict?
• Indigenous methods take time to design, plan &
develop
• Pressure from performance orientated donors cuts
short project assessments
• “Off the shelf” packages often fail – e.g. using the
Negev model but rain falls in the winter there, and
the summer elsewhere
• Large projects often use incentives such as food-forwork to meet targets
Zai planting pits in Yatenga,
Burkina Faso.
• The success of this indigenous technique is widely
acknowledged
• Since the early 1980s zai have been rapidly revived
• Over 8000 ha of degraded land brought back into
productivity by the late 1980s
• The Yatenga has very high population densities &
variable rainfall (ave 700mm)
• Suffers recurrent drought (in the 60s &70s)
• Lateritic soils with hard pans have low infiltration
capacities
• Farmers use stone contour bunds to reduce the
speed of runoff
• Zai collect and concentrate the runoff.
• Zai have a diameter of 20-30cm and depth of 1015cm, and no. 12,000-25,000/ha
• The larger the spacing, the more water can be
harvested
• Where barren land is rehabilitated yields can be
1200kg/ha in the first season
Zai planting pits
A crop of sorghum on a
rehabilitated field
• The project started by Oxfam as an agro-forestry
project & was completely rejected by the farmers
• It was participatory from the start. Farmers
designed, tested & evaluated the ‘improved’ zai.
They had a clear preference for stone bunds
• Contrary to recommendations, farmers often
start at the bottom of the field
• Wright (1984) comments that “illiterate farmers
make economic choices along with the rest of us
& should be allowed and trusted to do so”
• They may initially space barriers up to 50m apart
depending on available household labour
• Most farmers adopted this technique without any
project support, & following farmer-to-farmer
visits it inspired the revival of Tassa in Niger
Tassa in Niger
• The project in Niger started as a food-for-work
scheme comparing contour bunds & demi lunes.
Tassa, the indigenous technique was not
mentioned at all!
• Through a participatory approach the project
changed course
• Similarly a project in Ourihamiza, Niger, using
demi lunes was not adopted by local people
because of labour requirements, novel planting
designs & changing crops outside of cultural
expectations
• Very similar conclusions were drawn from tests
using semi-circular hoops in Kenya at Baringo,
Turkana & Kitui
Half moons in Niger
Layout of semi circular bunds
Promoting Farmer Innovation
• The UNSO project was launched in 1997 & piloted in
Kenya, Uganda & Tanzania to support innovative
dialogue & draw on farmers’ own knowledge
• ‘Farmer Innovators’ become active agents contributing to
change
• Through farmer-to-farmer visits, study tours and training
days FI are encouraged to become role models in the
community
• The main category of innovations was water harvesting
• The ultimate aim is to scale up and institutionalise the
methodology
Florence Akol (Uganda) – water harvesting in
bananas
• Her innovation is water
harvesting from the road
into her plantation with
soil fertility management.
She has a system of
trenches to circulate the
water which is held in
basins around individual
stools. This holistic
system is unique.
Ojok Christopher (Uganda) – water-borne
manuring system
• He lives on a 20ha plot.
After noticing an existing
orange tree produced
juicy fruits now traps all
the rain that falls on his
compound by using
trenches, & digging pits
below trees to collect
stemflow. The manure
from his cow goes into
the trenches & is
transported by the water
Summary
• It is clear that indigenous knowledge will play an
increasing role in the design & planning of WH
• The Red Sea Hills in Sudan shows how indigenous
knowledge is being used directly in a government
programme
• However, this is unusual. External factors such as
changed land tenure, increasing drought risk & migration
have changed practices
• In Darfur in Sudan, the trus system has been revived
• Projects in Africa based on engineering & hydrological
knowledge are often not adopted by the local people
• Successful projects were participatory from the outset
• They are flexible enough to include indigenous practices
chosen by farmers, such as the zai planting pits in
Yatenga, tassa in Niger
• With innovative dialogue & information exchange
between farmers & organisations, technical assistance &
materials can be provided
• Hopefully, indigenous knowledge will play an increasing
role in the design & planning of water harvesting
systems