The rapidly developing flood crisis in Pakistan: 16th August 2010

The flood crisis in Pakistan continues to develop with a surprising pace.  In an earlier post I suggested that this event might be Pakistan's equivalent of Hurricane Katrina (i.e. a wake-up call for effective disaster management), but now it is starting to look more like the equivalent of the Haiti Earthquake - i.e. an event that is so catastrophic that the coping capacity of the state is exceeded.  There is clearly now a need for a huge international response effort.

The PakMet FFD hydrograph data continue to plot the progress or otherwise of the flood waves downstream.  Most of the the first flood wave continues to be trapped between Guddu and Kotri.  The Kotri hydrograph continues to show alarmingly low discharge values (click read more below to see the remainder of this post):

 Thus, the majority of the water from the first wave is still in the landscape as the second wave approaches.  At Guddu the discharge is rising again:

Note that it is still substantially above the "exceptionally high" level.  The real concern however must lie in the area around Sukkur, where the water level has hardly fallen from the first event, and is now just starting to rise with the second:

Unfortunately, further heavy rainfall is occurring both in the upstream areas and those downstream as well.  The FFD warnings are now expressing quiet concerns about the barrage at Sukkur.  The politicians are a little more frank about the situation, according to this report in Dawn:

"The Sindh irrigation minister, Jam Saifullah Dharejo, said the dam in Sukkur faced a major test of its strength as flood waters coursed down the Indus River into Pakistan's highly populated agricultural heartland.  ''The coming four to five days are still crucial,'' he said.

Take a look at the Pakistan media reports here, here and here to get an idea of just how bad things are in Sindh now.  The prospect of 200,000 people being rendered homeless by a single part of this flood in a single day is quite extraordinary.

Meanwhile, life in the mountain areas to the north is extraordinarily difficult, with areas devastated by the 2005 earthquake being hit by fresh landslides overnight.  The Express Tribune has a short article on life in Gilgit, which remains effectively isolated from the outside world.  The headline is: "Gilgit travels back in time as flood cripples infrastructure", which given that electricity, food, water and medical facilities are all in a state of crisis, is no exaggeration. 

Pakistan flood update - 15th August 2010

The second flood wave is now starting to affect the most devastated areas of Sindh.  The PakMet FFD hydrograph for Guddu has started to show an increase in discharge once again:

Note that the flood level has been above the exceptionally high (danger) level for ten days now.  Downstream at Sukkur the water level continues to fall very slowly, again remaining well above the danger level:

Expect this to start to rise once again in the next few days. Meanwhile, the final downstream station at Kotri the flood level remains very surprisingly low:

Assuming that these values are correct this must mean that a vast volume of water is being stored in the landscape between Sukkur and Kotri.  The flood is certainly spreading across the plains, as this report on new flooding in Jaffarabad demonstrates.  This NASA MODIS satellite image shows the area around Sukkur.  Notice how the area flooded changes at Sukkur, presumably because of the restriction in the flow by bridges and barrages:

There is a first class UNOSAT flood extent map here.   It demonstrates the areas in which the flood is still spreading - a close look is quite horrifying actually - the scale of the disaster is so huge that the media are understandably struggling to provide an adequate picture of the extent.

To multiply the problems the new flood wave travelling down the river.  This must be a very worrying situation once the second flood reaches Sukkur.  Although smaller than the first wave, the cumulative effects and the existing damage to levees spells a potentially very difficult situation.

Meanwhile, the focus of the media coverage is now on the downstream areas.  With 20 million people now directly affected by the floods, this is unsurprising.  However, the situation upstream also remains critical.  The Pamir Times has a good report on the situation in Gilgit-Baltistan, which is effectively cut off downstream by the loss of the Karokoram Highway and upstream by the Attabad landslide dam:

"The devastating landslides and flash floods that resulted in death of over 120 people in different parts of Gilgit – Baltistan have also blocked supply routes increasing misery and sufferings of hundreds of thousands more.

Blockage of the Karakuram Highway since last week of July has resulted in depletion of POL products, including petrol, diesel and Kerosene oil in the entire regions.  Hospitals have been closed and hotels are shutting down due to absence of electricity.  Banks have also closed down temporarily because of lack of electricity.Supply of electricity to Gilgit has been cut off for more than one week due to destruction of power houses and transmission lines. Transportation system has also collapsed due to closure of fuel stations that relied entirely on supplies from down country through the Karakuram Highway.  In Gojal valley the boats have stopped ferrying passengers and goods because of depletion of fuel reserves. The local people are cut off from other parts of the region without proper medical facilities and supplies.  Ghizar, Astore, Diamir and the two districts of Baltistan are also facing similar situations. Hundreds of displaced families in different parts of the region have still not been reached by the government and relief agencies. One such example is of the displaced people of Gaise village in Diamir where the food reserves have reportedly finished and starvation is setting in. Local people have demanded of the government to intensify its efforts in Gilgit – Baltistan to end miseries of the suffering people.  Deaths due to starvation and malnutrition seem to be a sad possibility in some far flung parts of remote affected districts of Gilgit – Baltistan."

Jeff Master's remarkable blog has an article on the causes of the Pakistan floods.  It remains my plan to follow this up in the next few days, if I can find the time given everything that is going on.

Update on the flood wave in Pakistan, plus an update on the monsoon in India and on typhoon activity in the NW Pacific

The true magnitude of the disaster in Pakistan is now becoming clear - this appears to be the country's equivalent of Hurricane Katrina.  It has to be hoped that lessons are learnt both within the country and by the international community in terms of disaster risk reduction there.

In 2007 the World Health Organisation produced a flood potential map for Pakistan, which I reproduce below:

The flood wave is travelling down the Indus River at present, concentrated initially on the most westerly of the three main tributaries shown above.  The latest PakMet hydrographs show that the flood has now peaked at Taunsa and is rising downstream at Guddu.  Unfortunately the graphs are incomplete on the PakMet site (it appears they have a software issue) - I'll try to put this right later once they have corrected the error.  For locations see the Google Earth map I produced yesterday.

The flood routing model suggests that the peak should reach Guddu in about three days from the peak at Taunsa, and then take a further day to get to Sukkur and finally three days or so to reach the sea.  Hopefully there is sufficient warning to relocate people away from the water, but the potential for damage is high. The government (i.e. the NDMA) in Pakistan is once again coming under severe criticism for its response - this letter, written about Taunsa, gives a flavour of the concerns.  Whilst it is easy to criticise NDMA, the core issue probably remains a lack of investment and capacity building in this agency.  This needs to be corrected.  Unfortunately, the assassination of an MP in Karachi yesterday has also led to severe civil unrest in that city, which is only serving to magnify the range of problems facing Pakistan.

Meanwhile the emergency in Northwest Pakistan continues, but the operation is being hampered by further rain.  Reports now suggest that the loss of life is in the order of 1,400, but note that it is not unusual for estimates a few days into an emergency to be too high, with a further 3 million people reported to have been directly affected.  Stories about the event are truly heartbreaking - it is hard to imagine what it must be like to lose your children, house, belongings and livelihood to a single event.  The impact of the flood in mountain communities is well illustrated by this image, showing the loss of roads and bridges, and extensive riverbank erosion that has triggered house collapses:

 Meanwhile, across a large swathe of northern and western India rainfall activity in this monsoon remains low:

And typhoon activity in the Pacific is also unusually quiet - indeed global tropical cyclone activity is at its lowest level for the 30 year period for which reliable measurements are available (see image below from Ryan Maue's excellent site).  ACE is a measure of the energy expended by tropical cyclones.  Given that tropical cyclones are a major trigger of landslides, this is keeping the overall occurrence lower than might have been expected. 
 

The floods in Pakistan

In the UK the current floods in Pakistan are failing to gather the level of coverage that they deserve, although there has at least been some interest.  The death toll is currently standing at over 1,100 people, with a million or more directly affected.  Fortunately, the Attabad Dam appears to have avoided the worst of the rainfall, so far at least, and has remained intact, although the water level has risen.  It seems likely though that this disaster will have slowed the plans for lowering the lake level - at least I hope so as this would be a very bad time to start blasting.

The worst affected area so far has been the area that most people know as Northwest Frontier Province, recently renamed to Khyber-Pakhtoonkhwa province. This is the area, which borders Afghanistan, is where the majority of the fatalities have occurred.  This is a difficult region at the best of times, so expect some confusion about the true impacts over the next few days.  Daily rainfall records for this area are available from the Pakistan Meteorological Department here.  I have plotted the cumulative total rainfall for five stations in Khyber-Pakhtoonkhwa province - note that the average monthly rainfall for July for each station is included in the legend.  The magnitude of this rainfall event is clear - compare the actual monthly totals with the reported monthly averages.  The variation in monthly averages across the five stations looks odd, but is probably associated with the location of the mountain front, which provides a strong orographic effect.

The loss of life appears to have been the result of a combination of losses in the main rivers and their tributaries, flash floods in upper catchments, collapses of mud brick houses, and landslides.  As is often the case in complex disasters of this type, it is difficult to unpick the balance of the losses, but it is clear that there has been at least one substantial landslide event.  Several news agencies report a slide in the Olandar (sometimes spelt Ulandar) area of Besham (Bisham), which is said to have killed 60 people.  There are also isolated reports of smaller fatal landslides.  Given that this intense rainfall affected the Neelum valley and the area around Balakot, both of which were heavily damaged by landslides in the 2005 Kashmir earthquake, there is a strong likelihood that landsliding has been intense.

Meanwhile, the floods remain the main story.  Such is the size of the Indus river that the flood crest has yet to be reached for many areas, as the Indus hydrographs show:

Note that the flood peak at Besham, which in the past month has had a very similar hydrograph to Attabad, has now reduced substantially.

Meanwhile, concern is now focused in two areas.  First, as the flood waters (hopefully) recede in the upper catchments the full picture will emerge.  It may well be that some of the more remote areas have been unable to communicate the magnitude of the disaster to date, so the toll could rise.  There will also be concerns about the potential for disease associated with the flood waters.  Second, there are now deep worries about the combined effect of the flood wave traveling down the Indus reaching Sindh Province, in southwest Pakistan, at the same time as another burst of rainfall.  The most critical period appears to be from 4th to 7th August, when the director of the Pakistan Flood Forecasting Division, Hazrat Mir, is reported to have warned that "exceptionally high flood in the river and the expected rain were likely to gravely affect Pannu Aqil, Mithon Kot, Sehwan Sharif, Larkana, Dadu, Sukkur and Ghotki".  He is also reported to have added that there is an "urgent need to adopt precautionary measures. Low-lying areas, especially the ones in Sukkur and Ghotki, were likely to be affected the most. The FFD chief also expected flooding in Karachi, Hyderabad and Larkana because of the rain during this period"

First images from a visit to the Shiaolin landslide

Today, with two colleagues, I have visited the site of the Shiaolin landslide in Taiwan, which killed about 500 people on 8th August. I will write a longer analysis soon (we are due to go back tomorrow), but for now I will just provide a before and after image.

Before:


After (the village was at the foot of the slope):


And this is the aftermath of the flood caused by the collapse of the landslide dam:

Culvert failure video

Whilst this is not strictly a landslide, the video below of the failure of a culvert makes very interesting viewing. The ability of the channelled water to erode rapidly is a lesson that is often forgotten.



The video was captured by MWTW.com photojournalist Kevyn Fowler in Freeport, Maine during a storm.

Floods in France

France is currently suffering some terrible flooding that is also resulting in a serious threat of mudslides to the extent that some motorways (freeways) have had to be closed.

Although not really landslides, I felt I just had to show the following pictures of the Grangent reservoir on the Loire valley, which has trapped an extraordinary amount of debris washed down the river as a result of the rainfall:

Debris on the surface of the Grangent reservoir, France. From here.

More debris on the surface of the Grangent reservoir, France. Also from here.

There are also some fantastic pictures and videos, such as the image below, on this blog site (in French).

Hurricane landslides in Haiti

A perennial landslide story at this time of year is the triggering by a tropical cyclone of landslides in Haiti. This year the hurricane season has been particularly cruel, with three large events in a month. Hanna, the most recent, appears to have stalled close to Haiti for a day or so, causing torrential rainfall. At the moment reports suggest that 136 people have been killed in flash floods and landslides as a result of Hanna, but that figure may well rise as the picture becomes clearer. Unfortunately, there is another, very intense "Cape Verde" type hurricane (called Ike) lurking to the east. Current forecasts suggest that the track will swing north of Haiti (in fact Florida could get a direct hit), but at this stage such forecasts are at best tentative. A direct hit from a hurricane as large and intense as this, on the back of Hanna, could be disastrous for Haiti.

So why is Haiti so vulnerable to hurricanes? Basically, Haiti is the most extreme illustration of the impact of deforestation on landslides and flash floods. Haiti is the poorest country in the Caribbean - over half the population live on less that $1 per day ($1 is the recognised mark of extreme poverty) and over 75% live on less that $2. More that 60% of the working population do not have formal employment. The consequence of this has been extreme deforestation, primarily for firewood to create charcoal.

This is rather well illustrated by this Google Earth image:

The border between Haiti and the Dominican Republic is the river that runs across the centre of the image. On the west (leftish) side is Haiti, to the east (right) is the Dominican Republic. The contrast between the two is striking - in the Dominican Republic deforestation has been limited, in Haiti the loss of forest is almost total.

The result is that during hurricanes the landscape has little capacity to intercept and store water, and once flows across the surface begin the landscape rapidly erodes. This is perhaps best illustrated by the following Google Earth image of the city of Gonaives in the east of the country. Gonaives has been very seriously affected by erosion and landslides again in the most recent floods. The image shows the hills on the outskirts of the edge, with the suburbs clearly visible. The hills are clearly suffering from extreme deforestation. In September 2004, Hurricane Jeanne triggered mudslides and debris flows from these hills that killed over 3000 people in the city. Bearing in mind the fact that Haiti should be densely vegetated with tropical forest, the disaster that is the landscape in this country is all to clear to see. Unfortunately, posts about landslide disasters in Haiti will be a feature of this blog in the late summer for years to come.