SPATE IRRIGATION IN PAKISTAN

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SPATE IRRIGATION IN PAKISTAN
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History of spate irrigation in Pakistan
Some bunds in Balochistan are more than 5000
years old The construction of spurs and bunds in
the Bolan river (Balochistan) during dry period
was one of first opportunities to control
surface flows and resulted in strong population
increase In 2600 BC Source French
Archeological Mission
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Spate irrigation - globally
Pakistan has the single largest area under spate
irrigation The area is 9 of the total irrigated
area Even so it is completely ignored
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Spate irrigation in Pakistan where?
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HILL TORRENT AREAS
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DI KHAN
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TANK
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TAUNSA AREA
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DG KHAN
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KACCHI PLAINS
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KACCHI PLAINS MIDDLE SECTION
as elsewhere based on earthen bunds distance from
river as important as head tail huge fields many
braiding stream (flat gradient)
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Type of spate irrigation systems(1) large
systems along the Kohi Suleiman, Kirthar Range
and in Kacchi Plains
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Type of spate irrigation (2)smaller systems
coastal Las Bela, interior Balochistan, smaller
rivers from Koh-i-Sulaiman and Kirthar Range
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Type of spate irrigation(3) mini systems
mountain systems
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General typology

• Spate irrigation in Pakistan
• Worlds largest area under spate irrigation 1.4
  M ha!
• Equivalent to 9 of canal irrigated area
• Completely neglected
• Very low productivity compared to other countries
• Major poverty pocket in the country
• Important environmental functions
• Some areas short range from mountain to Indus
• Special characteristics
• Based on large earthen bunds and deflectors
• Overstretched area command area compared to
  floods is large many areas only irrigation lt 1
  in 5 years
• Few floods (lt5), elsewhere more floods
• Large fields
• Mainly flat and sandy areas
• Interventions
• Based on failed civil engineering concepts not
  appropriate to spate system high failure rate
  (65)
• Lost its dynamism no new development
• Role of local government in management was
  positive but is weakened
• Spate irrigation seen as nuisance (flood damage)
  not as potential

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Potentials

• Potential is large
• Water management
• Revive and resource local management by
  communities and local government
• Rationalize area under spate irrigation
• Ensure affordable availability of bulldozers in
  public or private sector
• Stay away from inappropriate civil engineering
  solutions, such as weirs and flood storage dams.
  Instead attenuate and regulate flood patterns
• Appropriate civil engineering solutions are flow
  dividers, fixing flood canal inlets, bed
  stabilizers, improved/ strengthened earthen bunds
  (gabion sections, abutments), guide bunds,
  controlled field inlets and overflow structures
• Improve drinking water supply improved shallow
  ponds and subsurface dams
• Combine spate irrigation with groundwater use and
  recharge

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Potentials

• Potential is large
• Agronomy and livestock
• Improved soil moisture conservation (mulching,
  ploughing, improved equipment)
• Improve yield of major crops such as sorghum by
  better varieties and better soil moisture
  conservation in Eritrea yield of sorghum is 8
  times more!!
• Better marketing and processing of promising
  minor crops (guar, sesame for instance)
• Improve prospects for local vegetables and
  medicinal plants
• Spate irrigated forestry (gum arabica)
• Improve local livestock varieties (Bagh Nari)
• Improved fodder for livestock

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Potentials

• Potential is large, if managed well
• Environment
• Stabilizes the area, avoid desertification
• Recharge of groundwater
• Local wetlands and lakes
• High biodiversity, indigeneous plants
• Low external input (organic) farming

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