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2011

PAKISTAN RAIN/FLOOD 2011

Report on Flash floods, breaches in canals and damage to infrastructure & agriculture sectors in Sind Province

(The period under report is from Aug 08 to Sep 03)

September 08, 2011

PAKISTAN FLOOD 2011 Rev 3.0

SPRCNT/FAO/ OSRO/PAK/013/CAN

Table of Contents

1.0 Summary 1

2.0 Rainfall and Flash Floods 1

3.0 Crop damages 6

4.0 Breaches 8

4.1 Badin 9

4.2 Mirpur Khas 16

4.3 Umerkot 19

4.4 Tando Muhammad Khan 21

4.5 Thatta 23

4.6 Tando Allah Yar 24

4.7 Sanghar 25

5.0 Results 26


SPRCNT/FAO/ OSRO/PAK/013/CAN Page 1 of 25

1.0 SUMMARY This report has been prepared in context of Letter of Agreement (LoA) signed between SUPARCO and FAO on 31 July 2011. This is second interim cumulative report covering the period from August 08 to September 03, 2011. The initial report covered the period from 08-23 August. Based on rapid mapping & analysis and a quick ground survey, damages to infrastructure, settlement, canal beaches and agriculture were identified in the initial report. A second spell of heavy monsoon rains in Northern Punjab and Southern Sind provinces, coupled with more breaches in canals and Left Bank Outfall Drain, have caused colossal damage. More than a million people in lower districts of Sind have been affected. The rains have devastated standing crops causing huge loss to economy. SUPARCO is monitoring the floods on daily basis with the assistance of satellite imagery and field teams have also surveyed some of the affected areas to validate the data extracted from satellite imagery.

The pre and post flood satellite imagery along with Satellite

Remote Sensing (RS) and Geographical Information Systems (GIS) techniques were used for the mapping of the affected areas/regions and carrying out assessment of damages caused by rain. Moderate resolution Imaging Spectro-radiometer (MODIS) data was used for calculating daily flood extent while for precise delineation of flood extent pre and post flood SPOT-5 satellite imagery was used.

This report elaborates an update after the 2nd spell of rains and

situational update on initial assessment. The reference space maps for 07 severely affected districts of Sind Province are part of this report.

2.0 Rainfall and Flash Floods

The summer rainfall of Pakistan is generally, converged during the periods of July to September. Monsoon from the Bay of Bengal is the main source of these rains. However, the mid latitude westerly disturbances, at some times, have also contributed on summer rainfalls. The maximum temperature in the major growing areas of crops generally ranged between 35oC to 45oC. From 1st August to 03 September 2011, in Punjab, the highest rain fall of the order of 415 mm was received in Lahore. About 12 stations in Punjab namely Bahawalnagar, Jhelum, Khanpur, Islamabad, Lahore, Mandi Bahudin,



Mangla, Murree, Noorpur Thal, Okara, Sargodha and Sialkot received rainfall above 200 mm. The source Rainfall data is through the courtesy of Pakistan Meteorological Department (PMD).

In Sind, the highest rain fall of the order of 591 mm was

received in Mithi. About 06 stations namely Badin, Chor, Mithi, B.N Abad, Padidan, Mirpur Khas, received rainfall above 200 mm. In KPK, the highest rain fall of the order of 377 mm was received in Kohat. About 05 stations namely Balakot, Dir, Kakul, Kohat, Parachinnar received rainfall above 200 mm. In Baluchistan the highest rain fall of the order of 141 mm was received in Kalat. The graph statistics are shown below



The cumulative rainfall in year 2010 and 2011 is shown hereunder



3.0 Crop damages

The months of August and September are symbolized by peak vegetative growth and a photosynthetic activity of a very high order. The Kharif crops grown during this period includes sugarcane, cotton, rice, fodders, vegetables, maize, pulses, oil- seeds and a large number of other minor crops.

The daily mapping of the areas under inundation and flash floods

was carried out using MODIS sensors of medium resolution of 250 m. This was compared with the pre flood satellite imagery. For detailed demarcation of flood extent fine resolution SPOT 5 satellite images were used. The agricultural area was worked out by overlaying agriculture mask on the flood extent map. For estimation of area under crops, the archived crop statistics were used to draw trend lines and to apportion fallow fields and areas under various crops.

Cotton is the most sensitive crop requiring 5 to 6 irrigations during

the growth period. However it does not compromise on an excellent drainage and well oxidized soil environment for its root system. All cotton under flood water for more than 3-4 days was taken as damaged. The rice crop has a foliar respiratory system that does not break by flooding so far it does not overtop the plants. This crop is about 2 feet high at an average at this stage. It is assumed that 50 percent of the flooded crop was subjected to deep inundation submerging the plants, with ultimate irreversible damage. The remaining 50 percent of the crop on peripheries of inundation escaped damage. The Kharif fodders are relatively in better position as these are generally 4 to 5 feet high. The fodders are still useful as silage even if these dry up. Despite this, a loss of 50 percent has been assumed.

The sugarcane crop is almost 11 month old in Sind province and

height of the crop is 5-7 feet. Sugarcane is a water loving crop. Generally sugarcane crop is not damaged by flash floods. At this stage of growth, the damages by flash flood are nominal. However, some damages would accrue by erosion through uprooting the crop. Furthermore the sugarcane would gain through provision of additional water.

The Kharif vegetables are nearing their end and major harvests

have already been made. The damage on this account is therefore ignorable. The Rabi vegetables are being sown. In affected areas these vegetable may have to be re-sown. Sowing of onion and tomato nurseries may be affected and these nurseries may have to be re-sown. The chilies crop in Kunri may be affected by prolonged flooding.

The geographic area affected by rains and flash floods in Sind up to

03 September 2011 was a little more than half a million ha. The



agricultural area affected was about 0.28 million ha. The statistics as workedout through use of satellite remote sensing technology are as follows:

The crop damages accrued to three main crops viz. cotton, rice and

fodders. The affected cotton area is 45.9 thousand ha and production loss is estimated at around 0.34 million bales. The rice area damaged is estimated at 32.4 thousand ha and rice production loss is expected at 99.9 thousand tons. The sugarcane crop was generally safe from any major loss. The damages estimates as determined by SUPARCO through satellite remote sensing are as follows.

Damage by rains and flash floods during 2011

Cotton Rice Fodders

Area yield Production

loss Area Yield Production

loss Area yield Production

loss Dist 000 ha kg/ha 000 bales 000 ha kg/ha 000 tons 000 ha tons/ha 000 tons

T.M.Khan 1.2 1430 9.8 2.1 3349 7.0 0.2 12.3 2.3 Badin 12.5 1508 111.3 27.5 3081 84.6 2.7 10.5 27.9 Thatta 0.1 1288 1.0 2.3 2989 7.0 0.2 10.9 2.1 Mirpur Khas 22.0 1153 149.2 0.3 2675 0.9 1.0 10.3 10.7 T.A.Yar 2.6 1376 21.3 0.0 0 0.0 0.4 11.7 4.2 Umer Kot 4.9 1015 29.2 0.0 0 0.0 0.6 9.1 5.3 Sanghar 2.5 1319 19.6 0.1 3005 0.4 0.1 13.5 1.6 45.9 1264.5 341.4 32.4 3087 99.9 5.1 10.5 54.0

Following assumptions have been taken into account to formulate the above results:

a. The official land utilization statistics of SIND released by erstwhile MINFA shows that the cultivated area in SIND is 4.89 million ha. The net sown area over a year is 2.81 million ha and fallow area over a year is 2.08 million ha. This is almost a ratio of 60% cropped area and 40% fallow area. However in view of our assessments it is assumed that cropped area is 70% and fallow area is 30%.

b. All cotton area under water has been damaged c. Fifty percent under rice and fodder crops was damaged d. No damage to sugarcane crop



e. No damage to orchards f. Pulses, maize, bajra, sorghum, damage is on negligible area

4. Breaches (2011)

The land surface gradient is generally horizontal in Sind and is generally slow to respond to surface and sub-surface drainage needs of the province. A 4600 cusecs capacity Left Bank Outfall (LBOD) spinal drain was designed to deliver 2000 cusecs into Shakoor Lake and the remaining 2600 cusecs to pass through Badin district into the Arabian Sea. The design of the drain does not allow runoff water to find an inlet into LBOD. The rain water either overtops the banks of the drain or farmers breach it to drain their field to the disadvantage of lower riparian. This inundated large areas in Tando Muhammad Khan, Badin and Mirpur Khas, displacing a large population from rural Sindh.

Several breaches in protective bunds of the canals have been

noted in Sindh province. The most prominent breaches were identified and delineated in district Badin, Mirpur khas, UmerKot, Tando Muhammad Khan, Thatta, Tando Allah Yar and Sangar.

Change detection based on multi-temporal and multi- resolution

satellite imagery was used to ascertain the location of breaches, their sizes, consequential damage to other infrastructure. Various base layers such as settlements, irrigation network, roads, railway lines and bunds were overlaid on to flood extent map.

The detail analysis of breaches is being carried out at SUPARCO’s Data Processing Labs and a 2-3 day field validation survey is being planned in the coming week in the rain affected districts of Sind Province. The situational update on the status of breaches in canals would be provided in next report.



4.1 Badin



4.2 Mirpur Khas



4.3 UmerKot



4.4 Tando Muhammad Khan



4.5 Thatta



4.6 Tando Allah Yar



4.7 Sanghar



5.0 Results

23‐Aug‐11 03‐Sep‐11

District Inundated Area (ha) Agri Area (ha) Inundated Area (ha) Agri Area (ha)

Badin 235,100 108,098 322,000 158,000

Mirpur Khas 92,000 56,600 96,000 58,000

T.M. Khan 17,000 11,300 28,000 17,400

Umer Kot 14,700 8,500 26,700 17,200

Thatta *NR *NR 14,000 11,700

Tando Allay Yar NR NR 15,800 10,600

Sanghar NR NR 15,600 8,300

* Not Reported

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