Floods: A major Catastrophe in PakistanEvery year destructive natural disasters occur worldwide affecting human lives, their daily lives, destructing infrastructure. Specifically, the developing countries endure high damages due to highly vulnerability to natural disasters due to lack of preparedness, prevention plans and inadequate infrastructure to deal with these catastrophes. In recent years, Flood has effected badly Pakistan. From 2005 to 2015, Floods have damaged infrastructure, destroyed homes, and impacted lives of over 25 million people. Some people were illegally living in flood detention areas because of poverty and homelessness.
Govt. of Pakistan spends billions of dollars on rescue, relief operations and maintenance of flood works annually. Flood policy is designed based on recommendations from provincial, local and federal agencies and various institutes have been setup to prevent and mitigate these disasters but statistics show no major decline flood-to-damage ratio in Indus Basin.In this study, the reasons of fluvial and flash floods in major areas of Pakistan, management policies, and flood prevention measures are investigated.
Finally, a comprehensive list of ideas based lectures delivered by teacher in class is presented.1. IntroductionPakistanis one of most vulnerable and disaster-prone country from natural disasters due to climatic change and its geographical location. Past researchers and scientists have placed Pakistan at ranked 16th among 170 nations based on climate change vulnerability index . Flood, one of the frequent natural disasters during the monsoon season occurs in Indus river basin. In 2010, the worst flood affected almost one fourth population of the country. According to statistics 8000 people lost their lives, 20 million people were seriously affected and lost their homes, destroyed standing crops spread around 2 million hectare and caused a total economic loss of 10 billion US dollars as shown in Figure 1. The poverty conditions in area, limited resources, low adaptive capacity and inadequate arrangement at national and local level aggravated the destruction.HDI (Human Development Index) and GDP indicators also indicated the weakness of the government’s response to a natural disaster at such level. According to economic reports Pakistan’s GDP in 2008 was estimated at US $164 billion and GDP per capita was $955 giving Pakistan a rank of 132nd. in 2009, according to the HDI report Pakistan was having 0.572 HDI, ranking Pakistan at 141 out of 182 countries . These statistics however revealed the weakness of government to tackle the natural hazards and rebuilt the infrastructure of the prone areas.By looking at the devastating effects of these natural hazards, researchers have widely accepted the role of risk reduction, prevention and mitigation. It is also further stressed to make a comprehensive policy among various disciplines to coup in such situations as local institutions are the first responder to carry out effective and responsible disaster risk reduction measures. The nature of flooding varies according to geographical location of area. Areas along both sides of Indus basin are flat and densely populated. In Indus Basin, fluvial floods are more damaging and devastating. . Flash floods or hill torrents (Figure 2) are the second most destructive type of flood. Hill torrents claim destruction of large areas of the country frequently .2. Fluvial Floods in Indus BasinMostly severe floods occur in Indus basin is due to monsoon season due to heavy rainfall. In addition, the melting of snow from glaciers during hot summer intensify the flow of flows in rivers. During this period, heavy rainfall also occurs in upper catchment area of Indus River in Kashmir valley. As a consequence of these factors, the river expands to entire floodplains.Figure 1: Flood losses details at national level against severe flooding years .In Indus basin, the nature of these fluvial floods varies depending upon the height of bed level as compared to the adjoining areas. Major flood occurs in lower Indus plain area as water over flows from riverbanks because of less difference of river bed level. However, in the lower part of the Indus this extra water do not return to the river. However illegal use of inundation areas leads to larger damages.Figure 2: Map of Pakistan showing hydrological and geographical features 2.1 Urban FloodingRapid urbanization linked with economic development and migration from rural areas to cities has increased population to uncontrollable extent. Because of this rapid growth in cities, the land space became unavailable and people start living in flood prone areas. Moreover, cities expand in surrounding farmlands where flood protection is lower. The drainage system becomes antiquated and insufficient for rainwater while prices of assets escalates. Zoning land and regulating land useare not done and local agencies are more reluctant to regulate the laws and inhibit development. Furthermore, no proper solid waste treatment and use of shopping bags has also reduced the efficiency of drainage system. Because of these reasons, major cities in Pakistan like Karachi, Lahore, and even Abbottabad became flooded during the normal rainfall.3. Flash floods in Indus BasinHilly areas of Pakistan including KPK, Kashmir, some areas of Baluchistan and Punjab receive flash floods typically due to high rainfall. In Kashmir and KPK the average rate of rainfall is high as compared to rest of hilly areas. However, heavy rainfall causes flash floods leading to severe damages to human lives as well as infrastructure in Baluchistan and Dera Ghazi Khan (D.G. Khan). In KPK, slash floods occur mainly due to sleep bed slope, which enhances the velocity of flow leading to erosion of banks. Provincial Government has taken few measures by constructing spurs to reduce the chances of erosion. Some dikes have been constructed in order to divert the flood at various locations and to minimize the effects of heavy rains.The high level of deforestation has occurred in past years caused the reduction in water retention by forest eco-system which has enhanced the devastating effects of flood occurrence. As a consequence, the surface water runoff along with sediment load due to erosion increases. This leads to landslides and damaging of riverine infrastructure. In Punjab province, some areas of Pothohar region face flash flooding. Islamabad and Rawalpindi both cities endure severe flash flooding during monsoon season due the overflow in Nullah Lai, flowing through centre of both cities.Most parts of Baluchistan Province are barren and having steep slopes which leads to flash floods during summer rainfall .4. Floods due to cyclonesCyclones and high tides are major causes of floods in coastal areas. In Pakistan, Makran is most affected area due to severe cyclones. Cyclones are usually generated in the Arabian Sea due to which severe rains throughout the region from gulf to south Asian coasts. However, the probability of occurrence of these cyclones is very low almost one cyclone occur per year in the Arabian Sea. Most of these cyclones finish at Omani coast. However, no severe past studies showed that no until now no devastating tidal flood has occur so far .5. Weaknesses in current flood’s monitoring systemThere are various risks factors involves increasing the vulnerability and severity of natural hazards in Pakistan. There include 1) Poor Infrastructure and no enforcement of land development and building codes; 2) Poor efficiency and no maintenance of early warning systems; 3) limited education and awareness on disaster and risk management; 4) corruption and non-serious attitude of government departments towards impoverished communities; 5) allocation of limited resources including manpower and limited coordination among various government disaster response agenciesPakistan has taken various measures including both structural and non-structural to deal with flood hazard to reduces flood losses. However the main ideas behind these measures is based on flood prevention. Mostly strategies are formed for rescue and relief actions. However, at local level in case of hazard no precise strategy has been seen yet to enhance the flood fighting abilities. Federal Government has initiated plan for flood mapping, but still no further progress has been seen and authentic product has been produced to integrate flood mapping into existing flood data.Although, government has taken new initiatives for structural and non-structural measures but lack of regular maintenance leading to failure. Major negligence has been reported in 2010 floods in maintenance of dike and flood emergency warning system.Corruption while dealing with funds has been reported. Federal government allocated funds and distributes them through flood agencies. These agencies further distributes among people on biased and political influence. On the other hand, the project approval guidelines set by flood agency are based on protecting the property, location and infrastructure of influential individuals and completely neglecting of areas and communities with lesser influence and importance. There is complete negligence has been observed in preventing deforestation in hilly areas because of involvement of political individuals.Indus basin is backbone of Pakistan social and economic infrastructure. Every year devastating records have been found while flooding in Indus basin. However, until now no seriousness has been shown by taking precise measurement to deal with fluctuations in Indus River.Soil erosion and sediment transport to lakes, dams and other reservoirs reduce the capacity of water storage and flood mitigation function. Regular sediments deposition may destabilise dikes during flooding. More often, because of sedimentation the water level rises in Indus River, leads to flooding of surrounding areas in lower Punjab and Sindh. Every year huge resources are spent on dredging purposes to restore flood conveyance capacity.The storage capacity of Pakistan is around 12% and since 1974 after Tarbela dam until now no major dam or reservoir has been constructed for storage, hence much water is lost in sea every year. Construction of new dams and reservoirs has been stopped by the political issue and inter-provincial disputes. Pakistan is more vulnerable to natural clematises as it has been suffering with severe draught and water shortage and later by devastating flood in 2010 .6. Flood Modelling, monitoring and forecastingWith advances in technology, it has been possible to certain limit to predict the extreme precipitation, and with monitoring and modelling of flood certain methods can be employed for improving flood prevention and mitigation. Z. Duan et al. used two gridded precipitation models along with VIC (Variable Infiltration Capacity) to predict the extreme precipitation and stream flow in Ganjiang River Basin, China. The simulated results with VIC model while using found to agree well with the observations .The U.S. Army Corps of Engineers (USACE) – Engineer Research and Development Centre (ERDC) Coastal and Hydraulics Laboratory (CHL) used their model to simulate the flooding of 2010 in Pakistan. This new computer model is used for simulation of flooding, prediction and estimation of total drawdown of the floodwaters, and estimates time for flood water to recede. Thousands of data points were incorporated and integrated from geographical, historical and satellite information. ERDC-CHL covers very large areas for flood simulations, hence the simulation times are relatively long. The simulations were carried to predict the peak propagation of the flood during the rising period and for estimation of time for flood water to recede. That is where the extremely robust algorithms implemented in DSS-WISE (a GIS based user friendly pre-processor) which take into account wetting and drying, simulates data accordingly .B. Ahmad et al. investigated and modelled flood conditions for Nullah Lai at Islamabad. They used HEC-RAS and HEC-GeoRAS hydrological models to outline the areas vulnerable to flood having different discharge values. Moreover, a topographic survey technique was employed targeting area from Kattarian to Gawalmandi Bridges to produce the DEM of the area. GIS technology has been used to demarcate the variation of topography and to find the inundation depths at various locations of the concerned area. The integrated modelling technique has been proved well todemarcate areas vulnerable to flood predicting inundation depths at a particular discharge value .7. Recommendation for Floods risk prevention and mitigation measuresBased on these weaknesses and discrepancies in current flood prevention and management system of Pakistan few recommendations are presented. These recommendations are structure and non-structure development of system to prevent, mitigate and reduce the devastating effects of floods. Flood protection is never absolute and might possible things can go wrong. The question is to what can communities can be protected at what cost of resources and how much of the remaining risk has to be accepted. Risk management analysis will be an appropriate method to deal with this challenge. The evaluation of health and safety of dikes, spurs, embankments and other flood works at is necessary. During dry period, cracks and fissures may develop in the embankments. Therefore, these structures need an effective monitoring coupled with regular maintenance before the onset of the flood season. Also, SOPs (Standard Operating Procedures) needs to be updated and improved. Based on latest research, these structures need to be redesigned and improved. The flood detention areas or wetting channels must be provided along the embankments in order to protect the bigger cities, major towns and infrastructure. Another strategy to make second defensive line of embankments to protect the most important areas can be adapted. Sedimentation may change the bed level of reservoirs, river and reservoirs. There is a need for establishment of new bench-marks to define new heights and strengths. Flood protection and maintenance works should be given due importance in budget plans irrespective of frequency of floods. Resources and investments need to be identified to cater for the future needs arising from future extreme events. Construction of new dams and reservoirs specifically at Kalabagh along the Indus River has been technically proved and effective measure to store the extra water flowing. As a result, the flooding in lower Punjab and Sindh can be reduced to significant level. On other hand, this dam can also enhanced the power production capacity of Pakistan. Provision of flood release or escape channels connecting the main rivers may reduce flood peak discharge. Adequate drainage facilities must be provided on roads, highways and other related infrastructures to evacuate flood water in order to provide protection to the cities and town and important installations such as power stations, nuclear installations, oil refineries and industries etc. Measures to regulate land control and implementation of laws for building development in the immediate areas at high risk of floods, landslides or dam must be implemented. Exceptions should be restricted to those uses which are of stringent necessity. The political influence must be rejected and an effective law must be prevailed at any cost. Capacity building and training of staff responsible for flood management, through short courses and trainings on flood fighting and protection, barrage management, and contingencies plans. More research and knowledge on floods is necessary to make better and effective plans for preventing and mitigating flood effects. This research should include modelling for extremeconditions based on history of past events. Existing models and future integrated modelling practices should be based on comparisons by applying and evaluating them within the same river basin. The integration of new knowledge into graduates is essential through research at national and International levels. An effective early-warning and forecasting system supported by meteorological must be installed at upper and lower catchment areas on Indus River. Efficient communication and coordination is required among federal, provincial and local disaster fighting agencies. There is a need for coordination system at district and tehsil administration system during emergencies. Efficient and strong communication links need to be established among disaster fighting agencies, press and public representatives. The widespread damages can be controlled through effective and improved coordination. Effective security measures should be ensured on all barrages and flood structures through police, Pakistan army and other related agencies. The public should be aware of being at risk. They must be encouraged to take their own flood prevention measures and be informed about how to act during flood their lives and belongings. Using district administration practical guidelines must be distributed on how to behave in that way. Moreover, areas at higher risk of flooding, people must be trained on regular basis about alert, rescue and safety measures.References F.K. Khan, A geography of Pakistan: environment, people and economy, Oxford University Press, Karachi, 1991. S. Deen, Pakistan 2010 floods. Policy gaps in disaster preparedness and response, International Journal of Disaster Risk Reduction 12 (2015) 341-349. I.H.D.I. UNDP, 2011. (Accessed 30 2018). M.A.U.R. Tariq, N. van de Giesen, Floods and flood management in Pakistan, Physics and Chemistry of the Earth, Parts A/B/C 47-48 (2012) 11-20. J.F. Jarrige, Excavation at Mehrgarh – Pakistan, South Asian Archaeology 1975 (1997) 76-87. Zheng Duan, Hongkai Gao, and Mouleong Tan, Extreme Precipitation and Floods: Monitoring, Modelling, and Forecasting, Advances in Meteorology, vol. 2017, Article ID 9350369, 3 pages, 2017. APA citation: Modeling Pakistan’s flooding (2010, October 8) retrieved 6 January 2019 from [Ahmad B., M.S. kaleem. M. Butt, Zakir H., (2010) Hydrological modelling and flood hazard mapping of Nullah Lai 2010, Vol 47. Pp 215-226