ORI GIN AL PA PER

A review of the assessment and mitigation of floodsin Sindh, Pakistan

Asadullah Kazi

Received: 6 June 2013 / Accepted: 27 August 2013 / Published online: 5 September 2013� Springer Science+Business Media Dordrecht 2013

Abstract This paper lays emphasis on the riverine floods (natural hazards), which are

more frequent than other types of flood affecting Sindh. Nevertheless, a brief description of

the other types of floods is also included. River Indus and its tributaries cut across Pakistan.

The river basin so evolved covers approximately 65 % of the total area of the country. The

major part of the river basin in Pakistan lies in the province of Sindh, which is prone to

floods. It poses a major environmental hazard, particularly when the flood waters overtop, a

few km wide river channel; the natural floodplain, confined by the manmade levees (flood

protective embankments/bunds), several kilometers apart, constructed on both sides of the

channel, forms the riverine area (manmade flood plain). The latter, locally known as the

katcha area, is spread over an area totaling about 8,500 km2, and agricultural crops, which

are the backbone of economic prosperity of Sindh, are partly grown in the flood plain of

River Indus. The worst floods do not occur every year, but when they do, they play havoc

in the riverine area, occupied by crops. Furthermore, there are three barrages constructed at

Guddu, Sukkar, and Kotri, in which manmade feeder canals control the floods, as well as

enabling the river water to irrigate over 60,000 km2 of agricultural land, falling within the

command area of these canals. It may be noted that there are other types of flood, including

the pluvial floods, urban/stormwater floods, flash floods, and coastal, as well as ground-

water floods that also occur in Sindh. A brief description of these floods is also included,

and an attempt is made to make an assessment of occurrence of the riverine floods. Also,

suggestions are put forward to mitigate the influence of these floods, and through light on

participatory management practices considering safety, scientific, technical, social, and

political dimensions, aimed at mitigating and controlling the flood hazards.

Keywords Natural hazards � River � Flood � Sindh � Recurrence interval �Mitigation measures � Flood management

A. Kazi (&)Isra University, Hyderabad, Sindh, Pakistane-mail: asadkazi@isra.edu.pk

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Nat Hazards (2014) 70:839–864DOI 10.1007/s11069-013-0850-4

1 Introduction

Floods pose a major environmental hazard, which may be natural, or manmade (Mustafa

and Wescoat 1997; and National Disaster Management Authority 2010). They may be

defined as an abnormal rise in the water level of rivers which may result in overflowing of

water on the land, which is normally dry, or receiving more water than it can normally hold

(Anon 2013).

There are many types of flood (Nelson 2010) depending upon the climate, source of

water, and the topography of the area. Smith and Petley (2009), while describing several

environmental hazards, originating from tectonic and atmospheric influences, classify flood

hazards into riverine and coastal types. Nevertheless, there are several other types of

floods. The following is a rundown of the major type of floods, in general, together with

their sub-classification. For instance, riverine floods can be caused by a glacial melt as well

as an excessive rainfall. Similarly, coastal floods can be caused by a tsunami or a

cyclone.

• Riverine/overbank floods • Coastal floods Glacial melt Cyclone/ HurricaneRainfall Tsunami

• Urban/Storm water floods • Barrier lake floods• Pluvial floods Glacial - Barrier Lake• Flash flood/torrential rain Landslide - Barrier Lake

• Groundwater floods

This article focuses mainly on floods in Sindh. The riverine, urban/stormwater, pluvial,

and flash/torrential rain floods are dealt collectively, with emphasis on riverine floods,

which may or may not include rain-caused floods. The coastal, barrier lake, and ground-

water floods are covered briefly. For completeness, in the prominent surface features of

Pakistan and that of Sindh, which influence the occurrence of rainfall and glacial melt,

related riverine floods are also included.

2 Assessment of floods

In Pakistan, the province of Sindh, as shown in Fig. 1, is bounded by the province of

Punjab in the northeast; on its north and west-side lays Baluchistan, while its eastern side is

bordered by India, and it is constrained by the Arabian Sea in the south. The country shares

borders with Iran in the west, India in the southeast, Afghanistan in the northwest, and

China in the northeast.

The province of Sindh covers (141,000 km2) approximately 17.7 % of the total area of

Pakistan (796, 100 km2). It is approximately 580 km in length, with an average width of

about 280 km, which in places widen to nearly 440 km. The climate of Sindh is typically

hot and dry, placing it in the arid subtropical zone.

2.1 Physiography

Pakistan is a land with varied topographic and climatic contrasts. It can be divided into five

major topographic units, carved by different geomorphologic processes affecting those

units. These include the following: (1) the snow covered northern mountains, comprising

parts of the western Himalayan and Karakorum ranges with a small part of the Hindukush

range. The western mountains (2) consist of the Baluchistan Plateau in the form of Kirthar

range of mountains and Koh-e-Salman. The foothills of these mountains form the

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pediments and the piedmonts, sloping into the River Indus (3). The latter occupies the

central part of Sindh, flanked by the great desert of Thar (4) in the east, and the Kirthar

Mountains in the west. The southeastern tip of the Thar Desert is occupied by Karoonjhar

Hills, at the edge of the Runn of Kutch, adjoining the Arabian Sea (5), which truncates the

three longitudinal north–south-trending belts (2, 3, and 4), described above.

2.2 River Indus

Approximately this 3,000-km long river is one of the longest rivers in Asia. The catchment

of the River Indus is estimated at one million km2. Although, the river passes through a

number of countries, but approximately 65 % of the Indus Basin, so formed, lies in

Pakistan, covering about 75 % of the country area. The river rises in the Himalaya

Mountains of western Tibet near Lake Mansarovar. A part of its upper course, which flows

through narrow gorges in a rugged topography, essentially runs through India, and after

passing through Kashmir, it finally reaches Pakistan. From here downward, the river

ultimately drains into the Arabian Sea.

The length of River Indus in Pakistan is approximately 2,735 km. It is joined by several

major tributaries including the Beas, Sutlej, Ravi, Chenab, and Jhelum Rivers in the east.

The Kabul River, which is the largest western tributary, joins the Indus near Attock. The

upper part of the Indus plain, in Pakistan, mainly lays in Punjab, where the river continues

to be braided. All the major eastern tributaries meet at Panjnad. They all join the River

Fig. 1 Geographical map of Pakistan

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Indus at Mithankot (located in Punjab), approximately 100 km upstream of the northern

border of Sindh.

The province of Sindh lies between 23–35� and 28–30 north latitude, and 66–42 and

71–01� east longitude. It is about 580 km in length from north to south and on the average

about 280 km in breadth from east to west, and at a few places, the breadth is nearly 440

km. The lower part of the Indus plain in Pakistan extends in Sindh, where it adopts a

meandering pattern, essentially sloping to the south, with an average gradient of generally

\10–12 cm per km. The length of River Indus in Sindh is approximately 930 km, forming

an ‘S’ shaped curve with a major outer curvature near the city of Dadu toward the west,

and the inner one toward the east near the city of Hyderabad. Downstream of Hyderabad,

there used to be several natural distributaries forming estuaries emptying into the Arabian

Sea. Many of these estuaries, over the years, have abandoned due to regression of the sea.

However, those close to the sea have eventually been converted into creeks.

The wide alluvial floodplain (commonly known as the riverine or Kacha area) marked

by overtopping of the channel, through which the River Indus flows, is a major source of

livelihood, for the people of Sindh, who depend mostly on agriculture. River Indus, flowing

through Sindh, bisects it into the left bank and right bank regions. The riverine area is

spread over about 8,500 km2, lying on both the sides of the river channel, which is less

than a km to few km wide, confined between the two flood protection levees (embankments

or bunds), about 6–16-km apart. The levees were initially constructed to protect the

infrastructure likely to be affected by riverine floods. River discharge, during these floods,

exceeding 300,000 cusec was a common feature, while these levees were constructed. The

agricultural land lying on both sides of the channel was flooded annually to various degrees

and depths. Some 1.800 km2 of the riverine tract is reserved by the government as the

forestland, while 4,000 km2 is designated as the agricultural land, and the rest is covered

by villages, graveyards, and uncultivable wasteland. The land on either side of the riverine

area is considered fit for human settlements. Panhwar (2002) points out that the entire

riverine area was the most prosperous in the pre-barrage period, but was ruined in the

recent decades.

The alluvial plain of Sindh is conveniently divided into three zones: the upper zone

(siro), the middle zone (wicholo), and the lower zone (lar). In summer, the upper zone

stretching from Sukkur northward records the highest temperatures reaching more than

52 �C, and the dust storms are common, whereas the winters are cold with temperatures as

low as 6 �C are not uncommon. In the middle zone, stretching between Sukkur and

Hyderabad, as the term implies, the maximum temperature is lower than the one in the

upper zone, but higher than the one in the lower zone. It is usually hot during the day, while

the nights are generally much cooler and pleasant. The lower zone lying between Hy-

derabad and the Arabian Sea is very humid, and the southwesterly winds in the summer

and northeast winds in the winter seasons are common. In addition to the three zones

defined above, Sindh is bounded by the Thar Desert (Registan) in the east, and the foothills

(Kacho) of Kirthar range of mountains (Kohistan area). The climate of Thar ranges from a

very cold in winter to a very hot in the summer. The months of April, May, and June are

the hottest. The average maximum and minimum temperatures ranging between 41 and

24 �C are common, while in the winter months of December, January, and February, the

temperatures fluctuate between 9 and 28 �C. Most of the rainfall occurs between June and

September, averaging approximately 200 mm per year. The climate along the foothills of

Kirthar range varies in conformity with the adjacent regions of lar, wicholo, and siro

regions of the alluvial plains. The rainfall is generally manifested by the range of moun-

tains in the Kohistan area continuing in Baluchistan and leads to torrential/flash floods,

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accompanied by heavy sounds of gushing water flowing through well dissected and heavily

jointed mountain range in the area.

The timing and control of available water, particularly at places, where the water is

needed the most, are important. Once this balance is lost, either due to shortage or excess

of water, problems pop up. It is important to note that the major amount of riverine annual

flow of water either originate or pass through India (being the upper riparian) before

flowing into Pakistan (being the lower riparian).

Soon after the independence of the two countries in 1947, from the British rule, such a

riparian dispute erupted between India and Pakistan. It was through the intervention of the

United Nations that the Indus Waters Treaty (1960) was signed, and the matter was settled,

as for as the sharing of waters was concerned. Accordingly, the waters of the western rivers

were mainly assigned to Pakistan, while India was to exercise a full control over the inflow

of eastern rivers. Soon after signing of the Indus Waters Treaty, Pakistan accused India of

constructing dams on the western rivers (Jhelum and Chenab) seriously affecting its

economy. Such inter-country disputes are often referred to arbitration courts for final

settlement.

Furthermore, disagreements on the construction of dams have also crept up between the

provinces/regions within each country, among the upper and lower riparian communities

(Kazi 2010). For instance, both India and Pakistan are agrarian countries, and water is the

backbone of their economies. Nevertheless, India has many more rivers to manage its hold

back on economy, while Pakistan has only the River Indus and its tributaries (Jhelum and

Sutlej). The areas of Punjab relying on the waters of eastern rivers (Beas, Sutlej, and Ravi),

which were given to India, for its exclusive use, seriously affected fertile areas of Punjab,

relying on the supply of water from the eastern rivers. Although the problem was partly

solved by drawing the waters stored in the Mangla and Tarbella dams, constructed by

Pakistan on the Indus and Jhelum rivers, respectively, , a number of link canals diverting

water from the River Indus and River Jhelum were constructed for this purpose. This

seriously affected the lower riparian communities in Sindh and Baluchistan, who depended

on the water, which was diverted to Punjab. Consequently, due to the lack of sufficient

river water flowing into the sea, the sea water, particularly during the high tide period,

started invading the agricultural lands in the deltaic area (Kazi 2004b). Since 1992, more

than 1.2 million acre of land has been encroached by the sea, which in places has invaded

about 64 km of land area (IUCN 2005; Hashmi et al. 2012). Nevertheless, among other

things, the effect of global warming and the resulting rise in the sea level may not be

ignored in this connection. It is beyond the scope of this paper to go into the details of this

matter.

3 Riverine floods

Some basic concepts and details of flooding associated with rivers, in general, including

stages of floods are summarized by Nelson (2011). The same applies to floods associated

with the mighty River Indus. The United States Geological Survey maintains StreamMail

system for accessing the real-time river stage and the flow of any US stream or river in the

country. The information can be sought through the use of handheld wireless devices, or an

email to get the most recent information about the stage or stream-flow data at a particular

place.

Since its creation, in 1947, Pakistan has faced seventeen major floods, including the one

in 2010 (Ahmad et al. 2011), and the flood peak discharge of over 9 lac cusecs was

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recorded at Guddu and Sukkar Barrages. The climate change (Farooqi et al. 2005; Memon

2008), including seasonal variations in temperature, wind direction, intensity, and distri-

bution of rainfall, as well as the timing of glacial melt and outbursts of glacial lakes are

important factors controlling the onslaught of floods. The latter generally reaches maxi-

mum values in March and April (Akhtar 2011) and may continue up to June. The average

temperature of the summer months (May through August) in Sindh is 33.2 �C, and that of

the winter months (December through January) is 17.5 �C.

There are two sources of rainfall in Sindh. The heavy monsoon rainfall generally occurs

from June to September (during Kharif season), and southwestern monsoon occurs in the

summer season (Thompson and Perry Thompson and Perry 1997; Awan 2003). However, a

small part of the rainfall that enters Pakistan from the northeast and generally falls from

December to March (during Rabi season) is called winter or northeastern monsoon. The

summer monsoon involves the rain-bearing winds blowing from the Arabian Sea and the

Bay of Bengal onto the landmass in Sindh and Punjab, while the winds in the winter

monsoon reverse their direction. They have limited moisture, but start blowing in the

northeasterly direction from the lofty landmass of the Himalaya, Hindukush, and Ka-

rakorum mountains, as well as Baluchistan Plateau. These cooler winds bring a little

amount of rain to some parts of Punjab and Kohistan leading ultimately to the Arabian Sea,

while passing through the southwestern parts of Sindh. The area is characterized by scanty

and unpredictable rainfall. The average annual rainfall in Sindh is approximately 160 mm

(Muslehuddin and Faisal 2006). It is essentially caused by two types of seasonal winds

referred above.

Figures 2 and 3 illustrate the average annual rainfall and average summer monsoon

rainfall in Sindh. It may be noted that the average annual rainfall is approximately 1.5

times the rainfall in the monsoon period in the upper Sindh region, while in the lower

Sindh region, the monsoon rain is approximately 1.2 times the annual rainfall.

It is noteworthy that the monsoon of August 2010 brought with it the worst riverine

flood after a period of 80 years, affecting Khyber Pakhtunkhwa, lower Punjab, Baluchis-

tan, and Sindh regions. In adverse conditions, such floods often make the rivers surge and

overflow their levees, devastating the affected areas across the River Indus. The seasonal

rainfall over Sindh, during the summer monsoon in 2011, was exceptionally high (248 %

above normal) and was essentially accelerated by the water-bearing winds from the Bay of

Bengal (WMO and ESCAP (2011) as shown in Fig. 4. The resulting rainfall did not cause a

Fig. 2 Annual rainfall (mm)

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riverine flood, as compared to the flood of 2010, which was essentially caused by a very

high river discharge in Indus.

The normal rainfall in the monsoon season is highly variable with a mean of 125 mm. A

very small amount of rain, approximating 13 mm, under normal conditions, falls in the

winter season. The highest annual as wells the summer monsoon rainfall often occur along

the coastal areas near Tharparker, Badin, and Thatta regions, reaching more than 300 mm,

as reflected by the rainfall record of the years 2010 and 2011.

Fig. 3 Summer monsoonrainfall (mm) Muslehuddin andFaisal (2006)

Fig. 4 Track of monsoon winds from the Bay of Bengal to Arabian Sea. The Arrows and the inscriptions onthem specify the dates (day/month) and position of the monsoon winds approaching Sindh, during June–September, 2011 (adopted from WMO and ESCAP 2011)

Nat Hazards (2014) 70:839–864 845

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Unfortunately, the magnitude of the glacial inflow of water, like the rainfall, is not

constant for a given area. The amount of water discharging from these two sources,

carrying huge amount of sediment, finds its way through natural channels and streams

entering into the tributaries, ultimately collecting into the River Indus. At times, the

discharge of water flowing in a river channel exceeds its capacity to withhold the water

within natural confines. In order to accommodate this extra amount of water, the river

widens the channel by overtopping its banks, leading to floods. The flood water finds its

way through natural inundation low-lying areas (dhoras). These dhoras work as natural

waterways for the disposal of stormwater drainage. This is not necessarily true for the

floods, mainly attributed to rainfall.

In Sindh, these dhoras, occurring on the left (east) bank of the river, as identified by a

team of consultants working for the Sindh Irrigation and Drainage Authority through Louis

Berger Group and Indus Associated Consultants (2012) are shown in Fig. 5. The flow of

water, through these dhoras, during the onslaught of floods, in many instances, is totally or

partially blocked, among other things by, chocking as well as encroachments in the form of

human settlements, where an estimated five million people are living, owing to the lands

being fertile, providing a suitable hub of livestock.

The water accumulated in the rain-fed terrains as well as the flood plain of the river does

not necessarily return back to the river. The situation in Punjab is different from the one in

Sindh. In the topographic setup in the upper part of the River Indus, in Punjab, the spilling

water generally returns back to the river once the flood is over (Ahmad et al. 2011).

The River Indus in Sindh primarily flows at a higher elevation as compared to its

floodplain. This makes the river in Sindh particularly hazardous from a flood point of view,

because it flows along a ridge (Sindh Provincial Disaster Management Authority 2012).

Consequently, the spilled water, as well as the water, collected in depressions, would not

return back to the river channel. The only way to let the water revert back to the river is

through pumping or letting the stagnant water dry up through evaporation. In the mean-

time, nothing can be cultivated, until the land is flooded with water.

The period between 1967 and 1972 did not experience any discharge above 6 lac cusecs

(ft3/sec). The floods, if any, during this period, were essentially of the lower or medium

stage.

The flood stages are defined in Table 1. The first super flood, and documented in

Table 2, occurred in the year 1973, showing that a total of 10 super floods occurred, during

the period 1973 to 2010, spanning 43 years since the record of floods was kept at Guddu

Barrage. The design discharges of the Guddu, Sukkur, and Kotri Barrages are 12, 9

(reduced from the original 15) and 8.75 lac cusecs, respectively. Sukkur Barrage was the

first to be functional in 1932, followed by the Kotri Barrage in 1955, and lastly the Guddu

Barrage in 1965.

Prior to the construction of dams and barrages, the excess river water would overflow

the banks of the river, through inundation cannels (dhoras). Subsequently, the river was

confined by embankments (protection bunds/dykes/levees) to prevent flooding of the

adjoining low areas.

This led the way for the establishment of human settlements on both sides of the

embankments. However, due to neglect and lack of maintenance, as described in the

Revised Bund Manual (2008), these embankments are often subjected to different kinds of

failures, leading to floods, which affect the life, property, and infrastructure as well as

agriculture in the surrounding areas. Subsequent to construction of river-training works, in

the form of river protection bunds, diversion of river water is made through barrages fitted

with gated diversion weirs. The main canals in turn deliver water to branch canals,

846 Nat Hazards (2014) 70:839–864

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Fig. 5 Major Dhoras, identified on the left bank of river Indus adapted from Louis Berger Group and IndusAssociated Consultants (2012)

Nat Hazards (2014) 70:839–864 847

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distributaries, and minors. The inundation canals that would provide natural outlets to the

disposal of flood water were cut across and habited by new villages, towns, and cities.

These habitations and the infrastructure built to serve the community acted like barriers

in the natural flow of riverine flood waters. Nevertheless, the flood water would accumulate

in the natural lakes, spread in the low-lying areas. The latter were carved out by the free

flowing river, along the natural gradient, and any excess water would spill over the low-

lying areas, acting as lakes to store the spilled over water. But this is normally not enough

to combat the disaster posed by relatively high riverine floods in the past. The best

example, in this regard, is presented by the 2010 super flood, which caused immense to the

people living in the area confined between the embankments, as well as those affected by

the breaching of embankments and manmade canals.

Figure 6 illustrates the areas devastated by the breach of Tori band, which lies close to

the Ghauspur town of Kashmore district, upstream of the Sukkur Barrage. This breach

forced the flood water to gush into the areas mostly west (right bank) of the River Indus

embankment, breaching subsidiary bunds and passing through villages/towns near Mian Jo

Goth, Karam Pur, Jacobabad, Jaffarabad, Kirthar canal, Ustad Muhammad, Garhi Khairo,

and so worth. Consequently, many of the habitats were drowned, and the flood waters

reaching heights of a few meters remained trapped.

Subsequently, the Supreme Court of Pakistan constituted a Judicial Commission to

probe into the causes of the major breaches of embankments (bunds) in River Indus, during

the flood of the year 2010. The Judicial Commission Report (2010) thoughtfully stated that

unnatural causes, particularly institutional failure, were mainly responsible for the disaster.

Furthermore, the report exposed illegal encroachments, which had been allowed to go

Table 1 Flood stages in Sindhwith respect to Guddu Barrage

Discharge *: 01 lac cusec is equalto 100,000 cusecs; and 01 cusecis equal to 01 cubic foot persecond

S. no. Discharge* Stage

01 Up to 2.0 lac cusecs Normal

02 Up to 3.5 lac cusecs Low

03 Up to 5.0 lac cusecs Medium

04 Up to 7.0 lac cusecs High

05 Up to 9.0 lac cusecs Very high

06 Above 9.0 lac cusecs Super

Table 2 Super floods in Sindhwith respect to Guddu Barrage

Years Flow (lac cusecs)

10 super floods, in 43 years, from the time when the records becameavailable in 1967

1973 10.83

1975 10.25

1976 12.00

1978 11.55

1986 11.73

1988 11.62

1989 09.88

1992 10.86

1995 09.88

2010 11.48

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unchecked by the concerned authorities due to negligence, corruption, and above all poor

management. Emphasis was also placed on unauthorized diversions of flood waters by

influential landowners in Sindh, in connivance with or negligence of institutions related to

flood management (Water and Power Development Authority, Federal Flood Commission,

Indus River System Authority, as well as National and Provincial Disaster Management

Authorities, Pakistan Meteorological Department, and so forth). It is beyond the scope of

this paper to go individually into the details of the concerned institutions.

This riverine flood, which was partly culminated by heavy rains, is estimated to have

caused economic losses and damage worth US Dollar 9.5 billion. Some 200 lives were lost,

and nearly 17,500 villages destroyed.

The only alternative available was to let the trapped water evaporate, or else to pump

out and let the water drain into the river bed. Some water was drained into the manmade

canals, which too in many instances were loaded beyond their design capacity. Unfortu-

nately, the disaster management authority was ill-prepared to handle this menace. It may be

noted that the river route between Guddu and Sukkur Barrages was devastated, while the

one between Sukkur and Kotri Barrages was not affected. Three weeks after the incidence

at Tori, breaches were also reported near the cities of Thatta and Sijawal, downstream of

the Kotri Barrage. The former is located on the right bank, while the latter on the left bank

of the River Indus. Rajput (2010) has given an excellent account of the 2010 flood and

attributes breaches particularly downstream of the Kotri Barrage, as a shear negligence of

the concerned officials, responsible for the surveillance and protection of bunds. He argues

that the bunds are made of earth, and no matter how much money is spent on strengthening

of bunds; they will always stay at the mercy of rats and snakes. Regular surveillance,

particularly during the monsoon season, is, therefore, very important to check for the weak

spots or seepage through bunds. Revised Bund Manual (Government of Sindh 2008),

among other things, deals with common causes of failure of bunds and gives suggestions

dealing with guidelines on closing such breaches.

Fig. 6 Schematic sketch of the 2010 Flood waters following the breach of Tori Bund (adapted fromthewe.biz)

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The flood of a similar magnitude, in 1973, triggered a breach in the Ali Wahan Bund, a

few kilometers upstream of the Sukkur Barrage, on the left bank of the River Indus. This

incident did not cause much damage as compared to the one in 2010. The main reason

being that east of the Ali Wahan is that much of the area is occupied by the Thar Desert,

with limited settlements and infrastructure. For the people living in that area, the flood

acted as a blessing in disguise. It recharged the aquifers, making the water available at

shallow depth, and helped in the growth of agricultural crops, as well as accessibility of

fodder for the livestock, which are the main sources of their livelihood.

It may be noted that the River Indus in its long history has changed it course with the

passage of time. According to Lambrick (1975), the river has moved westward close to

Kirthar Mountain range in the west, and away from the Hakra River, which consequently

approached the Thar Desert, in the east. The latter is a lost river. Nevertheless, the lost river

left behind an alluvial floodplain, which together with the Thar Desert, could form a thick

aquifer.

It is pertinent to mention here that, prior to the signing of the Indus Waters Treaty,

Pakistan used to receive more than 160 million acre feet (MAF) of water per year, but

subsequent to the implementation of this Treaty, Pakistan was left with a river flow

averaging 137 MAF of water per year.

The major component of the annual river flow in Pakistan, amounting to nearly 60 %, is

derived from glacial melt of the Hindukush, Himalayan, and Karakorum Mountain ranges.

A lesser amount approximating approximately 40 % is attributed to rainfall (Asian

Development Bank 2010). The major inflow constituting 83 % of the total flow is gen-

erated in the Kharif Season, while the rabi season receives 17 % of the total inflow in the

region (Kazi 2004a).

There is a relationship between the inflow of water at the rim stations located in

Pakistan and the corresponding inflow on the upstream of Guddu Barrage. Figs. 7 and 8

show that a similar relationship occurs between the peak yearly discharges, at Sukkur and

Kotri Barrages, respectively (Louis Berger Group and Indus Associated Consultants 2012).

These barrages are, therefore, under designed and need to be remodeled so as to stop

failure of the protection embankments, causing immense loss of human life, livestock,

agricultural crops, and material goods. Efforts must also be made to avoid overtopping of

the free board, seepage, piping, blow outs, wave wash, and so forth of the embankments.

This also includes the canals off taking from the three barrages, as well as the minor canals

and other channels (Rajput, 2010) in the network.

It may be noted that the Mangla and Tarbela Dams were constructed in 1967 and 1974,

respectively, while the Sukkur, Kotri, and Guddu Barrages were built in 1932, 1955, and

1965, respectively. The lesser amount of river flow reaching Pakistan after the Indus

Waters Treaty has significantly altered the return period of riverine floods. For instance,

according to Akhtar (2011), the recurrence interval of a high discharge stage of flood at

Guddu Barrage is around 6 years, while that of a very high and the super flood is 8 and

10 years, respectively. Accordingly, the recurrence interval of the floods that took place in

the year 2010 was around 50 years. In a similar study, the recurrence interval and the

corresponding discharges, at all the three barrages in Sindh (namely, the Guddu, Sukkur,

and Kotri Barrages), are shown in Table 3.

It reveals that the Guddu and Sukkur Barrages can withstand almost same discharge for

a given return period. However, for the same the recurrence interval, the peak discharge at

the Kotri Barrage is much smaller. It is evident that none of the three barrages are capable

of passing the estimated discharges of floods with recurrence interval of more than

50 years.

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While Sindh was recovering from the impact of the unprecedented flood of 2010, it was

ravaged by yet another flood in the following year. It must be emphasized that the flood

that devastated Sindh in the year 2011 was not exclusively a riverine flood, but was

associated with abnormal rainfall. Much of the damage was caused by not being able to

dispose the flood water into the River Indus. This flood is known to have caused damage

worth US Dollar 3.7 billion (Government of Pakistan 2012).

Figure 9 compares the rainfall in 2010 and the one caused by an excessive rainfall in

2011. It may be noted that the flood of 2010, with its tumultuous flow of water in the River

1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010

Year

Dis

char

ge in

cus

ecs

Fig. 7 Peak discharges at upstream of Sukkur Barrage

Dis

char

ge in

cus

ecs

1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010

Year

Fig. 8 Peak discharges at upstream of Kotri Barrage

Nat Hazards (2014) 70:839–864 851

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Indus was further aggravated by flows from the Koh-e-Salman near Kirthar mountain

range. It mostly affected the right bank of the River Indus. However, the heavy rainfall in

2011 divested much of the left bank, inflicting lesser damage to settlements on the right

bank of the River Indus. Unfortunately, many of the low-lying areas on the right bank are

still not dewatered and are unfit for growing agricultural crops in the areas divested by the

floods of the year 2010. Clearly, it was the synchronization of the heavy rainfall, coupled

with the riverine flow, originating from the glacial melt of ice capped mountains, as well as

outburst of glacial lakes that heavily increased the discharge of River Indus and its trib-

utaries upstream of the Guddu Barrage in Sindh.

This flood caused one of the worst disasters, in the history of Sindh. The discharge of

the river between Guddu and Sukkur was so heavy that a breach occurred in the Tori Bund

(Fig. 6). The time lag between the stations is useful in mitigating the onslaught of

impending disaster. The time that the river flow takes place from one place to another is

given in Fig. 10. Accordingly, the time that the flood waters took to reach the area around

Thatta and Sijawal from Mithankot was approximately 1 week. Both banks of the Indus

dyke gave away to flood waters. These areas are located at a distance of approximately 60

miles east of Karachi and form a part of the Indus delta.

Table 3 Estimated peak dis-charges and recurrence intervalsof floods. Simplified from LouisBerger Group and Indus Associ-ated Consultants (2012)

Recurrence interval (Years) Peak discharges (lac cusec)

Guddu Sukkur Kotri

2 5.8 6.2 4.1

5 8.3 8.6 6.2

10 9.6 9.9 7.4

25 11.1 11.4 8.7

50 12.1 12.4 9.6

100 13.0 13.3 10.5

200 13.8 14.2 11.3

Fig. 9 Comparison of the amount of rainfall, which affected Sindh in 2010 and 2011

852 Nat Hazards (2014) 70:839–864

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In this regard, the last instance (2011) happened despite early warnings from the

international community (National Disaster Management Authority 2010). It may, how-

ever, be emphasized that the 2011 flood was evidently a different type of flood. It had a

little effect on the riverine flow of water, although it is generally recognized that when the

amount of rainfall in the catchment area of a river increases, the volume of inflow in the

river also increases (Akhtar 2011).

The time the flood waters take to reach Guddu Barrage, downstream of the Mithankot, is

around 24 h. Figure 10, schematically represents a sketch, giving details about time

intervals of super flood waters reaching from Mithankot, 20 km downstream of Panjnad

(where the five rivers of Punjab meet the River Indus), a few km north of the Guddu

Barrage in Sindh (Pakistan Meteorological Department 2010). It takes 48 h for the flood to

travel from Mithankot to Sukkur, and 126 h (almost 5 days) to reach Kotri from Mit-

hankot. This leaves enough time for the people to get ready for impending disaster and

adopt adequate measures for mitigating similar recurrent situations in the future.

3.1 Urban/stormwater

These floods are caused by excessive rainfall, where the volume of rainfall exceeds the

drainage capacity of the area. There are many examples of this type of flood in Sindh.

However, the most recent incident occurred in the year 2011 and this event was well

covered in print and electronic media of Sindh. It is estimated that in this flood, although

the number of lives lost was significantly less (480) than those (2000) of the flood event of

the year 2010. Nevertheless, in this instance, more villages were affected numbering

38,000, than those in the 2010 flood, which affected 17,500 villages.

Overtopping of wastewater drains in the urban areas of Sindh is a common concern, and

many of the streets are often flooded with wastewater. The situation often gets worst,

particularly after heavy rains, when runoff produced by the rainfall exceeds the drainage

capacity of the drains, which are employed for this purpose. In many instances, there is no

separate drainage system to take care of the disposal of stormwater. However, in some

situations, a combined sewer system is used into which both the sewage and rain water are

utilized. In most situations, the existing combined system in the form of open channels or

pipes is often chocked with garbage. In many instances, such systems are generally under

designed, and no consideration is given to the rapid expansion of multistory households,

and the migration of rural population to urban centers, adding more to the already con-

gested drainage system, in the absence of a proper stormwater drainage network.

3.2 Pluvial flood

The presence of paved streets and asphalt covered roads, in the thickly populated urban

areas, further worsens the situation. The percolation of water into the ground decreases and

the runoff exceed the drainage capacity, particularly during the intense periods of heavy

Mithankot 24 hrs Guddu 24 hrs Sukkur

Kotri 78 hrs72 hrsThattaFew hrsArabian Sea

Fig. 10 Travel time of super floods from Mithankot to Arabian Sea

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rainfall, giving rise to pluvial floods. Such conditions primarily occur during the summer

thunderstorms, often occurring during the monsoon season in Sindh.

3.3 Flash flood/torrential rain

A flood caused by heavy or excessive rainfall in a short period of time generates flash-

floods. Such floods are usually characterized by raging torrents, after heavy rains that rip

through riverbeds, urban streets, or mountain canyons, sweeping everything that comes in

their way. They can occur within minutes or a few hours of excessive rainfall. They can

also occur even if no rain has fallen, for instance, after a levee or a dam has failed.

Torrential rains causing flash floods produce much damage to settlements in the pediment

and piedmont areas in the upper region of Sindh. This type of terrain is occupied by the

Kirthar range of mountains, exposed along the west (right) bank of the River Indus, and is

locally called Kohistan. The high drainage density of this type of terrain is instrumental in

causing rapid damage, leaving little time for mitigating the influence of flash floods, in the

affected area. It may be noted that during torrential rains, the canals are normally closed

upstream to allow accumulated rainwater downstream to drain, through these canals.

3.4 Coastal floods

These floods, as the name implies, occur at areas along coastlines, as a consequence of

typhoon (hurricane), and unusually high tide, which among other things, may be caused by

oceanic earthquakes, which gives rise to a series of waves, impounding coastal settlements

and there about.

Consequently, floods may, however, also be caused by sea level rising upon global

warming, leading to encroachment (transgression) of the sea, on the landward side of the

coastline. Nevertheless, the rise of land due to tectonic processes may give rise to reju-

venation of the rivers, which at one time emptied into the sea. Such a process forces the sea

to retreat (regression), leading to the creation of more land. The two processes of trans-

gression and regression related to Arabian Sea in connection with the history of River

Indus are presented and explained in Figs. 11 and 12, respectively (Kazi 2004b).

Typhoons or cyclonic storms in the Arabian Sea often occur during the monsoon season

from late April till June. They are more common in the adjacent state of Gujarat in India,

but seldom affect the shore line of Sindh. In most instances, such cyclonic surges lose

much of their strength by the time they reach the coastal belt of Sindh. In adverse situa-

tions, they are accompanied by heavy rains and strong winds blowing in the Thatta, Badin,

Karachi, and Shah Bunder areas. During the past 50 years, a number of cyclones, including

the ones in 1964, 1993, 1999, 2003, 2004, 2007, 2009, and 2010, have stuck the coastal

areas of Sindh, causing floods in the above-mentioned areas. The livelihood of the people

living in the affected areas is adversely affected by the recurrence of such hazardous

events.

3.5 Barrier lake floods

There is no record of large scale barrier lakes in Sindh. Such lakes are often triggered by

landslide debris which acts as a dam across the river, forcing the water to rise on the

upstream of the dam so created. The rising level of water, beyond a certain level, in the

absence of a spillway, is destined to cause a flood on the upper reaches of the river. Such

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dams are essentially temporary and are often removed by the pressure of the stored water.

The sudden failure/collapse of such dams can lead to devastation on downstream side of

the dam. Although there is hardly any chance for a situation to occur on the River Indus,

the chances are that such temporary barrier lakes may be formed on the tributary rills,

formed on the Kirthar Mountains, and located on the right bank of the River Indus.

Barrier glacial lakes are mostly found in the glacial terrains. There are numerous such

lakes, in the mountain chains, north of Pakistan. Such lakes are formed by the retreat of

glaciers. The retreating glaciers leave behind moraines, which act as barriers, to the flow of

glacial melt waters. It is expected that global warming of the planet earth is likely to give

rise to the formation of many more barrier glacial lakes in the Himalayan, Karakorum, and

Hindukush Mountain areas. The failure of such lakes will release huge quantities of water,

which will ultimately end up into the River Indus. These may not only commensurate

riverine floods in the Indus Plain, but at the same time, raise the level of Arabian Sea.

3.6 Groundwater floods

These floods occur, when the level of water in the ground rises above the surface. Such

instances are more common in the basements of buildings, located below the groundwater

table. Sindh is prone to this type of flood, particularly in areas located on the left bank of

River Indus. Prior to the construction of irrigation canals, there was no such problem in

Sindh, and the water table used to be several meters below the ground surface. As more

Fig. 11 Degradation of Indus Delta

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water became available for agriculture, subsequently upon the construction of barrages and

distribution canals, the formers started growing more crops.

In the absence of adequate drainage to remove the excess water, the water table started

rising close to the surface, bringing soluble salts with it. This gave rise to the problem of water

logging and salinity in several parts of agricultural lands in Sindh, as well as basement

structures in some urban areas. A number of manmade seepage cannels totaling 837 (Table 4)

were constructed to collect the seepage water and drain it into the 160 km main spinal drain as

part of the Left Bank Outfall Drain project (LBOD), which covered the regions, falling within

the command areas of the Sukkur and Kotri barrages, consisting of the areas in Nawabshah,

Mirpurkhas, and Sanghar. Together, these manmade seepage channels were designed to drain

5 million, acre of land, which constitute 38 % of the 13 million acre fit for human settlements.

The remaining 62 % of the area is without any drainage facility. The system was so designed

that it would also drain 200 mm of rainwater, accumulated over a period of 7 days, and that of

400 mm in 15 days (Rajput 2012). As illustrated in Fig. 13, the collected saline seepage as

well as the rainwater would ultimately drains up to 2000 cusecs into the Dhoro Puran Outfall

Drain leading to Shakoor Dhand (Lake), a body of water shared by India and Pakistan.

The LBOD was later extended to include the Tidal Link, designed to carry 6150 cusecs of

water. It drained the water collected in the Khadhan Pateji Outfall Drain into the Arabian

Sea. The Tidal Link together with the tail reach part of the LBOD later proved to be

problematic, leading to worsening of floods of the southern districts of Badin and Thatta.

The construction of LBOD was blamed for altering the natural flow pattern, generally

from the north to south, in the area. Nevertheless, the project benefited farmers in

Fig. 12 Restoration of Indus Delta

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Nawabshah, Sanghar, and Mirpurkhas Districts, and brought some 1.25 million acres of

waterlogged land, which is back under cultivation.

The devastation of the floods of 2010 and 2011, caused by riverine and excessive

concentrated rainfall, has left behind many lessons for the functions of the Flood Cell

hosted by the Federal Flood Commission of Pakistan, as well as the Irrigation Management

Authority and the Provincial Disaster Management Authorities in the respective provinces

of Pakistan. Unfortunately, much of the review plans for restoration and reconstruction

work is done after the floods are over. However, the implementation of a particular strategy

gives rise to some other problem(s).

The need for a holistic approach must not be ignored. It is expected that Louis Berger

Group and Indus Associated Consultants (2012), working for the Sindh Irrigation and

Drainage Authority, will come up with structural and nonstructural solutions in the

preparation of Regional Plan, as part of the Water Sector Improvement Project, including

mitigation of floods in Sindh.

4 Mitigation measures

The commonly adopted ways to abate floods are classified into structural and nonstructural,

varieties (Petry 2002). In the former type, attempt is made to keep the water away from the

people, while in the latter type, measures are taken to keep the people away from the flood

waters. An effective flood mitigation or protection system is generally a mix of structural

as well as nonstructural measures, aimed at preventing or reducing flood damages, at all

levels of rural as well as urban areas. It calls for participation of government organizations

and involvement of flood risk community in adequately handling this issue, which is

detrimental in overall development of the country.

4.1 Structural measures

Construction of several measures, such as embankments (bunds), bridges, barrages, river-

training works, and other measures, is often adopted to suit the diverse local conditions. It

Table 4 Statistics of seepage channels and bunds in Sindh

Barrage Gudducommandarea

Sukkurcommandarea

Kotricommandarea

TotalareaDrainage channel

(1) Number of Channels 5 361 361 837 947

– 110 110

(2) Length of channels(Km)

101 3,054 3,248 6,303 7852

– 1,549 1,549

(3) Drainage area (acre) 1,50,000 19,70,000 17,90,000 39,10,000 51,80,000

– 12,70,000 12,70,000

Length embankment(Bund) (km)

Riverine bunds along both sides of the floodplain 1,930

Flood protection bunds along the mountainous area ofKirthar range (Kohistan Area)

190

Total (km) 2,120

The second row (if any) in each column of the designated row number presents statistics of LBOD seepagechannels, in the Sukkur and Kotri Command areas. There is no LBOD in the Guddu Command area

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Fig. 13 Left bank outfall main drain (LBOD), including Spinal Drain, Khadhan Pateji Outfall Drain(KPOD), Dhoro Puran Outfall Drain (DPOD), and Tidal Link (adapted from Asian Development Bank 2000)

858 Nat Hazards (2014) 70:839–864

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also requires timely cleaning, de-silting of water retention structures, and deepening of the

natural inundation canals, well before the onset of predicted floods. The buildings in flood

prone areas should be erected on elevated spots. Ideally, the floodplain areas should be free

from any development, so that the impending flood could accommodate flows with min-

imal risk. Any new development should, therefore, analyze the impact of impending flood.

The entire Riverine tract of Sindh is mostly confined by bunds (Table 4). This structural

maneuver has altered the natural course of the river. It was meant at protection of major

urban settlements, as well as the protection of an extensive network of irrigation channels.

All these bunds are made of earth, and they need regular maintenance and vigilance,

particularly during and after the flood has receded. The guidelines about the design, pro-

tection, and maintenance of bunds are specified in the ‘‘Revised Bund Manual’’ published

by the Government of Sindh (2008).

Dams are also built to store the flood water. However, the Mangla and Tarbela dams

which were essentially built to store water and generate electricity are not feasible for

preventing floods. As a matter of fact, these dams are commonly filled in early spring

Fig. 14 Proposed location of structural intervention: connecting the river Indus with the ancient course of(Ghaggar) Hakra River. Adapted from crystalinks.com/indusmap.gif

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before the onslaught of floods, which are essentially accompanying summer monsoon

rainfall. There is no point in waiting for the summer monsoon rainfall; for instances, when

the monsoon rainfall fails to come, it would not be possible to fill the dams and use the

stored water for agricultural, industrial, and domestic purposes. Therefore, it would be

unwise to leave the dams unfilled and wait for the monsoon rainfall to fill the dams.

The past experience in Sindh has amply demonstrated that the existing protective

measures are not adequate in preventing riverine floods in Sindh. The problem is mainly

manifested at the onslaught of flood water after it travels down the Mithankot, a place

where all the tributaries of Punjab meet the ferocious River Indus.

Therefore, there is a need to find a suitable location to divert the flow of floodwater,

upstream of the Guddu Barrage, and downstream of the Mithankot area, toward southeast

area into the Cholistan Desert of the province of Punjab in the ancient course of (Ghaggar)

Hakra River as illustrated in Fig. 14. This figure, in addition to the relevant information,

contains a lot of other information to bring home the reader to overall geographical setup

of the region when the Hakra River was one of the major rivers.

It may be noted that the Cholistan Desert lies in the floodplain of the former (Ghaggar)

Hakro River. This river used to exist east of the River Indus; traces of the abandoned

human settlements, along the banks of this river, are still in existence. Figure 14 illustrates

the proposed location of connecting the River Indus with the ancient course of (Ghaggar)

Hakra River, in an attempt to prevent flooding of the area downstream of the Guddu

Barrage. Such intervention(s) will be a long way in controlling riverine floods in habited

areas of Sindh.

Furthermore, it will divert the flood waters to the Cholistan and the Thar Deserts in

Punjab and Sindh, respectively. The Cholistan Desert is an extension of the Thar Desert in

Sindh. Both the deserts are devoid of fresh water, and the flow of flood water, as well as the

percolation of this water in the underlying aquifer, will be a great source of relief for the

inhabitants of the two desert areas.

The term Hakra River must not be confused with Hakro Dhoro (Fig. 4); the latter is

perhaps the remnant of the river channel of the former. The complaint of the Punjab

Government that every year, approximately 14 million acre feet of water lost between

Sukkur and Kotri Barrage is not accounted for (Khan 2002). Perhaps, this situation is

created by the leakage of water through buried inundation channels of the River Indus

conveying waters to the floodplain of the abandoned Hara River. More work is needed to

discover such channels, which may be used to divert the flood water into the much needed

groundwater in the Thar Desert.

4.2 Nonstructural measures

The structural approach mainly relied on the construction of embankments. The non-

structural on the other hand deals with flood forecasting and flood warning systems. These

systems are in use in many countries of the world and are generally based on obtained from

the meteorological networks and river flow records. The information obtained from these

networks is used by weather forecasters to estimate the expected amount of rainfall in

space and time at different locations within the country; similarly, based on the record of

actual river discharges in the past, one can predict the return period or the probability of a

given amount of river discharge at a given river gauging station (Akhtar 2011; Kazi

2004a). The former task is performed by the Pakistan Meteorological Department, while

the latter by the Water and Power Development Authority in Pakistan. The importance of

these two institutions cannot be overemphasized.

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Since 1965, there has been a gradual rise in the precipitation events, and the same is true

for the rise of temperature in Pakistan (Rasul et al. 2012). This is an important event related

to the issue of global warming. It has significantly affected the flow regime and the amount

of water flowing, through the River Indus. Furthermore, recent studies have shown that the

sea level in the Arabian Sea is rising at the rate of approximately 1.2 mm per year (Shaikh

et al. 2011). This poses a threat to communities living close to the coastline.

The River Indus used to carry more than 400 million tons of sediment loads per year

into the Arabian Sea. This load of sediments together with high discharge of the River

culminated in discharging approximately 150 million acre feet of water into the Arabian

Sea. This was too much for the tide- and wave-dominated processes to counter act, leading

to a net deposition of sediments at the River Indus mouth (Kazi 2004b). This caused the sea

to retreat and the Indus Delta to go through a process of aggradations. This situation is the

opposite of what is currently happening, wherein the sea is transgressing landwards.

The best solution would be to let the sediments accumulate in the Delta. This can be

achieved by letting more sediment loaded flow through the River Indus. However, the

construction of dams and barrages has prevented the sediments to flow downward. Fur-

thermore, the discharge of water down the River has decreased due to demand for more water

by the upper riparian. Every attempt needs to find a compromise solution to the problem. The

supply of more water to Sindh will lead to more floods, and this requires remodeling of the

river structures, as well as the distribution channels off taking from the barrage headwork.

5 Flood management

The control of flood hazards is a national task of paramount importance. Human management

of any hazard, including floods, must address the three basic dimensions of the hazard. These

consist of risk, exposure, and vulnerability (Mustafa and Wescoat 1997). The risk, as defined

earlier, deals with aspects of recurrence interval, duration, and severity, while the exposure is

the number of people and the economic resources exposed to the event; vulnerability is

concerned with the condition and situation that render a society susceptible to damage.

Therefore, for a proper and efficient participatory approach to ensure a maximum level

of safety, integrated risk and disaster management strategies are important. This approach

is successfully deployed in Austria (Leitgeb and Rudoff-Miklau 2004). The same is

summarized in Fig. 15. It involves risk assessment and mitigation, preventive measures

and preparedness, disaster management including rescue, relief, rehabilitation, and

reconstruction. The importance of community participation and political will, in the whole

exercise, cannot be overemphasized.

National Disaster Management Authority and Federal Flood Commission in Pakistan,

deal with disaster calamities. The latter deals with multi-hazard assessment of vulnera-

bility, and risk for each district of Pakistan, while the former exclusively looks after flood-

related matters. Like the United States Geological Survey, an information system for

accessing the real-time river stage and the flow of any stream or river in the country should

be initiated. There is also a dire need for the construction flood zoning map of each district

in Pakistan. Included in such maps should be identification of areas suitable for play

grounds, schools, hospitals, residential accommodation, and so forth. Areas likely to be

affected by 100-, 50-, 20-, and 5-year floods should also be delineated. Guidelines, on how

to escape or manage once the flood has affected an area, should be clearly publicized.

There are useful guidelines on ‘‘Floodplain Development Standards prepared by the

‘‘Central Regional Planning and Development Board,’’ United States of America. This

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information is available at www.stcplanning.org. There are 13 Floodplain Facts Sheet

including the one on Floodway Encroachments described under Floodplain Facts # 12.

In connection with ‘‘Floodplain Management,’’ it is recommended that, among other

things, any development must not increase the flood hazard on other properties. However,

‘‘Floodways’’ are areas where fill or other development is likely to divert flow and con-

tribute to increased water depth during a flood. An ‘‘Encroachment,’’ in this context, is any

floodplain development activity that could obstruct flood flows. The latter is more general

than the former, which is more specific.

Flood-retaining embankments/bunds are an important element of flood protection in

Sindh. Unfortunately, these structures have in the past been breached deliberately or

naturally. Deliberately breached bunds are due to interference by the irrigation authorities

to relieve pressure on urban settlements from the fear of drowning, or to save barrages,

when the flood discharge is expected to exceed the design capacity of the barrage. Human

interference also plays a part in making breaches, upstream of their villages, or agricultural

lands, to save them from floods and let the others bear the burden of floods. Surveillance

and vigilance must be on alert; at least the endangered bunds may be breached by human

interference. Natural breaches are often due to poor maintenance and negligence on the

part of people responsible for keeping an eye on the condition of bunds.

Flood warning systems using telecommunication networks and so forth must be

established to inform, in advance, the people, likely to be affected by the impending flood.

Indeed, an early flood warning system is a key determinant of flood management. When

properly installed, this system should identify the amount of time available for residents, to

implement the emergency measures and to protect valuables or to evacuee the area during

severe flood events. It is clear from the past experiences in the flood affected areas, and the

flood management policy in Pakistan, that the concerned agencies, whether public or

Fig. 15 An integrated participatory approach in combating floods, linking risk assessment, prevention,disaster management, and regeneration

862 Nat Hazards (2014) 70:839–864

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private, are accustomed to take floods as a natural phenomenon and wake up to find a quick

fit solution to the problem, when it is too late.

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