SPATE IRRIGATION IN PAKISTAN1.3

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

Spate irrigation - globally

Country Year of

Irrigation Total Irrigated

Area (ha) Spate Irrigated

Area(ha)

Spate Irrigation as % of Total Irrigation

Algeria 1992 555,500 110,000 19.8 Eritrea 1993 28,124 15,630 55.6 Libya 1987/1997 470,000 53,000 11.3 Morocco 1989 1,258,200 165,000 13.1 Pakistan 1990 15,729,448 1,402,448 8.9 Somalia 1984 200,000 150,000 75.0 Sudan 1997/1987 1,946,000 280,000 14.4 Tunisia 1991 385,000 30,000 7.8 Yemen 1987/1997 485,000 193,000 39.8 Source: FAO Aquastat; Hadera 2001; Kohler 1999

Pakistan has the single largest area under spate irrigationThe area is 9% of the total irrigated areaEven so – it is completely ignored

Spate irrigation in Pakistan – where?

Major area

NWFP DI Khan, Tank, Laki Marwat, Bannu, Karak

Punjab DG Khan, Rajanpur, Mianwali

Sindh Dadu, Larkana, Jamshoro, Thatta, Karachi

Balochistan Kacchi, Sibi, Jal Magsi, Kharan, Qila Saifullah, Musakhel, Barkhan, Lorelai, Las Bela

HILL TORRENT AREAS

DI KHAN

TANK

TAUNSA AREA

DG KHAN

KACCHI PLAINS

KACCHI PLAINS MIDDLE SECTION

as elsewhere based on earthen bundsdistance from river as important as head tailhuge fieldsmany braiding stream (flat gradient)

Type of spate irrigation systems:(1) large systems along the Kohi Suleiman,

Kirthar Range and in Kacchi Plains

Type of spate irrigation (2)smaller systems –

coastal Las Bela, interior Balochistan, smaller rivers from Koh-i-Sulaiman and Kirthar Range

Type of spate irrigation(3) mini systems – mountain systems

General typologySpate irrigation in Pakistan:- World’s 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 IndusSpecial characteristics- Based on large earthen bunds and deflectors- Overstretched area – command area compared to floods is

large – many areas only irrigation < 1 in 5 years- Few floods (<5), elsewhere more floods- Large fields- Mainly flat and sandy areasInterventions- 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

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

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

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