Increasing vulnerability to floods in new development areas: evidence from Ho Chi Minh City

Abstract

Purpose Flooding is an emerging problem in Ho Chi Minh City (HCMC), Vietnam, and is fast becoming a major barrier to its ongoing development. While flooding is presently of nuisance value, there is a growing concern that a combination of rapid urban expansion and climate changes will significantly exacerbate the problem. There has been a trend of population being rapidly accommodated in new urban areas, which are considered highly vulnerable to floods, while the development strategy by the local government still attracts more property investments into the three new districts on the right side of Saigon River. This paper aims to discuss the increase in the number of residences vulnerable to flooding, to underline the need for more appropriate future spatial development. For the vision, an application of compact and resilient theories to strategic planning and management of this city is proposed to reduce vulnerability. This paper also highlights the need to better understand growing vulnerability to floods related to urban expansion over low-lying former wetlands and the more important role of planning spatial development accompanied with transportation investment which can contribute to flooding resilience. Design/methodology/approach This research uses combined-methods geographical information system (GIS) analysis based on secondary data of flood records, population distributions, property development (with the details of 270 housing projects compiled as part of this research) and flooding simulation. This allows an integrated approach to the theories of urban resilience and compactness to discuss the implication of spatial planning and management in relevance to flooding vulnerability. Findings The flooding situation in HCMC is an evidence of inappropriate urban expansion leading to increase in flooding vulnerability. Although climate change impacts are obvious, the rapid population growth and associated accommodation development are believed to be the key cause which has not been solved. It was found that the three new emerging districts (District 2, 9 and ThuDuc) are highly vulnerable to floods, but the local government still implements the plan for attracted investments in housing without an integrated flooding management. This is also in line with the development pattern of many coastal cities in Southeast Asia, as economic development can be seen as a driving factor. Research limitations/implications The data of property development are diversified from different sources which have been compiled by this research from the basic map of housing investments from a governmental body, the Department of Construction. The number of projects was limited to 270 per over 500 projects, but this still sufficiently supports the evidence of increasing accommodation in new development districts. Practical implications HCMC needs neater strategies for planning and management of spatial development to minimize the areas vulnerable to floods: creating more compact spaces in the central areas (Zone 1) protected by the current flooding management system, and offering more resilient spaces for new development areas (Zone 2), by improving the resilience of transportation system. Nevertheless, a similar combination of compact spaces and resilient spaces in emerging districts could also be incorporated into the existing developments, and sustainable drainage systems or underground water storage in buildings could also be included in the design to compensate for the former wetlands lost. Social implications This paper highlights the need to better understand growing vulnerability to floods related to urban expansion over low-lying former wetlands and emphasizes the more important role of planning spatial development accompanied with transportation investment which can contribute to flooding resilience. Coastal cities in southeast countries need to utilize the former-land, whereas feasibility of new land for urban expansion needs to be thoroughly considered under risk of natural disasters. Originality/value A combination of compact spaces with improved urban resilience is an alternative approach to decrease the flooding risk beyond that of traditional resistant systems and underlines the increasingly important role of urban planning and management to combat the future impacts of floods.

Exposure of manufacturing firms to future sea level rise in Ho Chi Minh City, Vietnam

“…Major parts of the city are built on low-lying marshlands, being part of a complex river delta which makes the city extremely sensitive to various flood sources. Nowadays, more than 50% of the city is regularly affected by flooding caused by high tides, heavy rainfall and storm surges (Duy et al, 2018). As the southern parts of the city are directly connected to the East Sea, many districts (Quans) are projected to be exposed to SLR by 2070 (Hanson et al, 2011).…”

“…To date, the HCMC region generates almost 40% of the country's GDP and accounts for around 70% of its export revenue growing rate (Katzschner, Schwartze, Thanh, & Schmidt, 2016). The economic development of HCMC is notably attributed to the city's location and its attraction for the labor force (Duy, Chapman, Tight, Linh, & Thuong, 2018). Moreover, FDI has been encouraged through a series of laws, policies and investments, primary distributed within the Southeast region including HCMC.…”

“…First, the SLR has to be understood as one of many factors for exposure to flooding. Due to Phi (2013) and Duy et al (2018), the exposure to flooding of HCMC is not only increased by the SLR, but also by manifold and self-enhancing processes. Data on e.g.…”

“…As the latest IPCC report (2014) postulates, particularly the risk of flooding in coastal megacities is rapidly rising. Ho Chi Minh City (HCMC), the largest city and economic powerhouse of Vietnam, provides an appropriate example for a location facing manifold challenges due to its notably high levels in current and future flood exposure and projected sea level rise (SLR) (ADB, 2010;Downes et al, 2016;Downes & Storch, 2014;Duy, Chapman, Tight, Linh, & Thuong, 2018;Nicholls et al, 2007).…”

“…As firms are already frequently located in floodprone areas on the fringe of the city and are equipped with hard-to-change and immovable infrastructure, particularly firms in the manufacturing sector are at the frontline in terms of loss and damage caused by flooding (Neise, Revilla Diez, & Garschagen, 2018). Recently, there has been extensive research on the impact of flooding in HCMC (Arouri, Nguyen, & Youssef, 2015;Balica, Dinh, Popescu, Vo, & Pham, 2014;Dang & Kumar, 2017;Downes et al, 2016;Downes & Storch, 2014;Duy et al, 2018), mostly focussing on the impact of flooding on communities and households and risk-adapted land use planning. However, little research exists on firms' exposure to future SLR inundation, although political frameworks such as the Sendai Framework for Disaster Risk Reduction 2015-2030 highlight firms and businesses as important actors for implementing an integrative and effective flood risk governance.…”