Planning for Risk and Resilience: Ho Chi Minh City Resilience Planning Project - Essay Example

PLANNING FOR RISK AND RESILIENCE: CASE STUDY Ho Chi Minh Resilience Planning Project Introduction Studies have placed Vietnam as one of the countries that has been greatly affected by climate change. Vietnam has been placed by studies as among the top ten countries ranked in terms of both the total and the actual share of land and population located in low-lying coastal areas below 10m above men seal level (AMSL) (McGranahan, Balk, and Anderson, 2007). Studies carried out to affirm the geographical extensive study on urban flood risk and the vulnerability of port cities confirmed that HCNC is among the top to be affected by flooding (Nicholas et al., 2008a). Background to the study Flooding is a part of our nature and can occur as flash floods, river floods and coastal floods (Oldershaw, 2001). The resilience that is required to cope with climate change that may bring about flooding and other natural calamities is inclusive and it requires a robust system and capacity, which is not in existence in many developing countries. Climate resilience in cities around the world can be due to the fact that there is existence of infrastructure, but poor urban populations often do not benefit from these infrastructures or are vulnerable because of their dependence on substandard infrastructure. Foundations like the Rockefeller are in recent time shown a lot of interest to partner with the the south Asian community to foster a development project that will promote climate change resilience. The foundation has provided grants to the Institute of Development Studies to complete a rapid governance and capacity assessment of 10 South east Asian cities, HCMC been one of them. Another institution, Asian Development Bank (ADB), presented a starting point for dealing the likely climate change impacts, in particular those relating to infrastructure development. According to ADB, Ho Chi Minh City (HCMC) ranks among the 10 top cities in the world with populations most likely to be severely affected by climate change. This is significant as it makes Vietnam to be vulnerable HCMC accounting for 23% of national gross domestic product (GDP) and 20% of foreign direct investment. HCMC is vulnerable as presented by the ADB because; I. It is barely above sea level – 40%-45% of land cover in HCMC is 0–1m in elevation, 15%-20% is 1-2m, and very little land sits above 4m; II. It has a large and growing population… and the dynamic economy draws migrants from all over the country; III. Local development patterns are also affecting vulnerability and the local climate -urban development, for example, has decreased infiltration and causes localized flooding; and IV. Current climate and hydrodynamics are already extreme and are expected to intensify, so there will be more severe storms, storm surges, and tidal flooding. Geographical occupation of HCNC It is with no doubt that HCNC represents one of the most dynamic example of rapid urban development of the last 20 years. This city epitomizes other emerging coastal megacity and exhibiting increasing exposure levels to climate risks. The city is locate in a low elevation intra-tropical coastal zone northeast of the Mekong delta and 50 km inland from the south china sea, this makes the city to experience significant annual variations of climatic and weather extremes. This geographical description makes the city to be considered a hot spot of vulnerability to the impacts of climate change (ADB, 2010; Carew-Reid, 2007; Dasgupta et al., 2007). Climate change is already evident in Vietnam with temperature increasing by 0.5oC and sea level increasing by ca. 0.20 m over the last 50 years (Monre, 2009). Local climate hence makes HCMC to experience some risk that are as a result of climate change, the significant impacts that are related to this climatic changes are flood risk, thermal stress, energy security and water resources (Ho, 2007, 2008; ADB, 2010; Storch, Downes, Katzschner, & Thinh, 2011; Storch et al., 2009; Yusuf & Francisco, 2009). Multi-level governance in the city The residents of HCMC have deal with the impacts of flood-related problems occurring in cycles of floods and dry spells each year. The city residents have devised means of adapting to the flood cycle by taking advantage of the benefits of the situation and at the same time reducing the damages causes by floods. For example, farmers have adopted their calendars to guide in the planting of different crops, building drainage canals and flood dykes. This has provided the integrated local remedy of the local people and the government as the government’s policy of enhancing integrated coexistent of the local people with the floods since the floods cannot be eliminated, they have learned to accept the variations in the seasonal flows. Urban development trends and exposure to flood risks The urban flooding that has been experienced in recent times is wanting and that does not make HCMC to be exceptional. The city is already exposed to multiple flood risks. Only 55% of the current urban area of HCMC lies 1 m above the mean sea level and only 28% is above 2 m. This fact makes the city particularly vulnerability to inundation from even small changes in future sea-level. The flooding that the city has experienced has caused severe disruption on regular basis with multiple consequences (Storch et al., 2009). The flooding takes the forms of urban flush and pluvial flooding, this is a result of prolonged heavy rainfall leading to overland flow and ponding, and it is a common occurrence on many streets. The inner urban flood has been occurring in HCMC and it is not something new but the rate at which it has been occurring can be attributed to climate change (Ho, 2007, 2008; Storch et al., 2009). Though the climatic increase is related to the exposure of the city, urbanization can also be attributing to be a source of future risks in of flood. The city was original founded in on high grounds, but recently it has concentrated itself by infilling of open spaces or the development and extension of existing building footprints. Another concern is the HCMC’s rapid growth of both planned and informal expansions into its lower-lying and formal wetland surroundings. Urbanization can thus be said to have caused the degradation of valuable multifunctional natural areas in the urban margin, the channeling natural of water ways, the sealing of surfaces to differing degrees, the creation of impermeable surfaces and increasing surface run run-off. This has prompted to the creation of hardscape feature and the loss for the space of water, including natural retention and detention areas diminishing the role of the natural drainage systems. The consequence of this is that the city becomes more vulnerable flood risk for both the population and assets in the existing settlement. In the coming time, in relation to the underlying demographic structure of Vietnam, the strong rural-urban pull of HCMC and the government’s own development targets, a significant amount of urban development has to be considered. The built environment has a design life of some decades and settlement patterns and urban form often display greater durability, these developments will greatly shape the spatial pattern and long tern vulnerabilities of urban agglomerations for decades to come. It is for this reason that anticipatory decisions have to be undertaken to steer cities like HCMC towards low risk development which would have very huge benefits over the coming decades (Bicknell, Dodman, & Satterthwaite, 2009; Hallegatte & Corfee- Morlot, 2011). It is therefore very important to plan and guide from the beginning the direction of spatial development and how buildings and infrastructure can be adapted to minimize flood risk exposure in an integrated manner. If the city is to continue with haphazard planning and urbanization continue to take place then further reduced detention and infiltration will be experienced exposing more people and assets on the city at risk to flooding. Actions will also be required to be taken urgently as if they are to be taken in future there will less flexibility to adapt to them and this will make it to be costly (Frankhauser, Smith, & Tol, 1999; Fuchs, Conran, & Louis, 2011). The flood risks to HCMC are increasing and will continue to increase under the imminent urban growth and climatic changes, appropriate actions should be taken. Managing these risks and exposure to flooding will be a crucial component of climate change adoption. Many authors and scholars have suggested special planning is very critical in adaptation to climate change (Adger, Arnell, & Tompkins, 2005; Adger et al., 2007; Bulkeley, 2006; Füssel, 2007; Hallegatte, 2009; Preston, Westaway, & Yuen, 2011). The project will be beneficial to be people in the city as it seeks to: Improve the local flooding forecasting so as to plan to resilience during the times of flooding. Improve the lives of the people by providing clean water in the flood-prone parts of the city. Improvement of the environment. Preparation of measures to deal with climate change. However, there are challenges facing this project especially due to the incompatibility of the different dyke systems used in the mitigation of the floods. Furthermore, the flooding is extensive covering a vast part of the city. Loosening decision policy There is huge importance of effective land use planning as a strategy and a key tool for sustainable adaptation and the understanding of the relationship between future urbanization and climate change impacts; land-use planning is seen as having a key role to play in developing strategies in climate proofing HCMC. Department of Natural Resources and Environment (DONRE) have the power to determine the overall land use, spatial zoning and environmental quality of HCMC. As such, DONRE possess executive powers over one of the most important instruments for the adaptation of HCMC to climate change. There is a great problem when it comes to decision making in HCMC and this can be a hindrance to an implementation of a policy. There is a barrier to the integration of adaptation measures into land use planning, DONRE views this as the lack of tools and methodologies to instruct and inform the policy makers. There is need for tools to assess the quality of existing knowledge regarding the emerging spatial challenges and to identify information gaps was raised by DONRE (Storch. 2009). The mitigation measures on the project are planned according to their key vulnerabilities. Immediate mitigation measures are planned in medium term of up to 2050 while complex mitigation measures are planned on long term basis of up to 2100. Managing tidal and fluvial floods Tidal and fluvial floods have been reported to be the most dangerous flood sources in HCMC. Records have shown that the maximum tide height of HCMC has been increased about 10cm from 2009 to 2012. On additional to this the fluvial flooding both upstream and downstream of HCMC is becoming more unpredictable due to unexpected sea level rise, heavy rainfall and tropical cyclones. A good method to mitigate this risk would be a well-integrated flood management system involving different industries and services. The solution should not solely be based on a convention drainage and infrastructure approach, but also on a wide range of services (Parkison and mark, 2008). There should also be the strengthening of cross-sectorial and cross departmental communication to enhance coordination among all stakeholders. Urban planning and urban design approaches should be manage flooding in HCMC, this will go a long way in mitigating tidal and fluvial flood control. These facts have prompted for the recommendation of a number of structural and non-structural measures measure for tidal and fluvial flood management. It has been note that from the governance system in HCMC has really influenced the planning decisions especially those that were really taken at the hydrological catchment of the Saigon- dong Nai Rivers and the Mekong Delta. The general urban planning design strategies for dealing with tidal and fluvial floods for HCMC can be classified into three main steps 1. Identifying flood prone areas It is very important if flood prone areas with future flood prone areas are identified first, this will give the basis of any management decision and measures is established. Information about the flood-prone areas, as well as emergency evacuation plans should be spread spread to the whole public, with major priority given to neighborhoods situated in flood risk zones. 2. Making space for flood water The significance encroachment of urban of urban structures into the tidal areas and the floodplains strongly result in the increase of the tide level in HCMC. For this reason in order to lessen the flood risk more spaces for flood retention should be reclaimed. This strategy ensures that the floodwater will be kept or diverted, and slowly released to rivers and canals once flood event are over. 3. Structural protection Physical protection structure are also an effective way to avoid floodwater damage to buildings and infrastructure, especially in neighborhoods already situated in flood risk areas, and where relocation is no longer possible. The structural protection measures can also be applied in urban areas where critical buildings and infrastructures are located. The strategies above are general strategies that are put in place for managing current and future floods, some specific strategies can be put in place to control the floods in HCMC, they include; i. Flood hazard mapping This refers to the use of maps for communicating flood hazards and flood risks. This aids in ensuring that there is facilitation of flood plain zoning and other land use planning measures. This is not only a supplementary tool for decision makers in both land use and emergency planning but also a communication tool to inform inhabitants about flood risks, helping to prevent future damage. ii. Re-naturalize Rivers and Channels In many occasions the rivers in and channels in HCMC have been significantly narrowed and occupied by housing structures and uncollected solid waste, this result in flood water blockage and reduction of flow capacity. Additionally, the embankments in HCMC usually are lined with sealing materials such as stones and concrete. This embankment will partly reduce water infiltration capacity, increase flow velocity to downstream areas and hence, increase downstream floods. Re-naturalizing a river means to bring it near to its original state, enhancing infiltration, reclaiming storage potential and providing more spaces for floodwater. Moreover, denaturalization helps to reduce bank erosion and enhances the bank along rivers. iii. Preserve floodplains Flood plains are flat areas adjacent to rivers or stream and experience high probable floods such as 10 or 20 year flood. Natural floodplains provide space for streams and rivers to expand during periods of flooding and dissipate the energy of high peak flows. For this reason they will provide a natural flood control and reduce downstream flood risks. They also help non-point source pollution and provide habitat for both flora and fauna (Sipes, 2010). iv. Decentralized urban basins Typically, flood events will cause the water level in rivers and channels to rapidly increase, which will lead to inundation due to insufficient storage capacity. it is possible to divert excess floodwater from rivers and channels to the basins into a network of urban basins, where floodwater will slowly be infiltrated into the basin grounds and released back to the water network when flood events are over, or when river capacity is available. Conclusion Vietnam as one of the countries that has been greatly affected by climate change as seen by the high prevalent rate of flooding. This project seeks provide citywide resilience strategy to deal with HCMC’s current and future flood risks. The people and government of Vietnam have engaged in integrated mitigation strategies which are meant to enable people to co-exist with the effects of the floods. 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