Beneath the Flood: How Greener City Planning Can Unblock HCMC Waterways

We’ve all seen the images online of people attempting to ride their scooters through city streets flooded in waist-deep water, drenched, miserable but determined. In some ways, the images seem to celebrate the resilience of Vietnam’s city dwellers but a look at what lies beneath those flood waters shows another tale of rising tides, stalled projects and a sharp cry for better foresight.

Saigon seen from above reveals a lego-like cluster of low-rise retail and residential buildings punctuated by iron and glass mega-stars like the Landmark 81, Bitexco Financial Tower and Vietcombank tower. Small patches of green color the otherwise very concrete landscape. The developments are separated by the Saigon River, which barges through the center of it all like a pulsing vein, bringing life to the city by way of commerce as well as increasing the risk of flooding with its ever-rising water levels during the rainy season.

City planning and well-designed waterways in HCMC

Le Corbusier, the iconic 1930s Swiss-French architect, urban designer, artist and pioneer of modern architecture, once wrote that “The materials of city planning are: sky, space, trees, steel and cement; in that order and that hierarchy.”

Rather than allowing cities to develop in the typical hodge-podge development style of the past, Le Corbusier believed that urban areas could be planned to be organized, efficient and tranquil. Fast forward to 2018, almost a century later and city planning is still a hot topic worldwide, though some cities are just better at it than others, often out of necessity.

The Danish city of Copenhagen, which nearly burned to the ground twice in the 1700s, was forced to redesign itself to survive. This is where the forward-thinking Danish design really began, Ho Chi Minh City-based, Danish architect and interior designer Fong-Chan Paw Zeuthen told #iAMHCMC. Zeuthen is founder and owner of KAZE Interior Design Studio, which has been responsible for landmark commercial projects, luxury residential builds and hotels throughout Vietnam and Cambodia. Danish design is known internationally for its iconic style and insistence on sustainability as well as its focus on building with the same demand for “sky, space and trees” that inspired Le Corbusier.

Now, while everyone (animal or human) can attest to the fact that we would all like a lot more of the above list, are they really necessary in a city where space is at a premium? When it comes to flood prevention, the answer according to experts is a resounding yes.

What Happens When Urban Planning Can’t Keep Up With Urban Development in HCMC?

According to “Effects of Urban Development on Floods” a survey by C.P. Donrad for the US Geological Survey, one solution for alleviating flooding is to design around it. Successful city planning means placing green spaces that can handle excess water in flood-prone zones rather than choosing those areas for large-scale developments. Impermeable surfaces (such as concrete sidewalks and roads) combined with drainage systems that lack the capacity to handle the increased population and development in Ho Chi Minh City have contributed to a year-on-year increase in flooding, property damage and even loss of life. The most recent storm, a typhoon nicknamed Usagi, which hit HCMC hard this last November, caused widespread flooding throughout the city and one death.

In addition, Vietnam was ranked 6th globally on the 2018 Climate Risk Index list compiled annually by German NGO Germanwatch due to its high number of climate-related losses (both financial and human). Weather calamities are inevitable but climate and development experts reveal that the effects of flooding on urban areas are something that is largely within our control.

When the Buildings Go Up in Saigon How Can the Water Go Down?

“There is a connection between the height of a building and how far you have to dig down to build the foundation, especially when you build on a swamp”, Zeuthen explained to #iAMHCMC. “When you penetrate that far into the ground you have to move the soil somewhere, and the water will have to find another way around.” The rush to build all these new apartments in Ho Chi Minh City by 2020 may increase flooding by overtaxing the drainage systems as well as rerouting underground waterways to other areas, she continued. Nearly half the city lies less than one meter above sea level and more than two-thirds are susceptible to major flooding. Groundwater and soil extraction can also cause the earth to sink, which may have an effect on flooding in the future. Development projects should consider these factors from the outset, Zeuthen concluded.

Zeuthen is not the only one concerned.

According to the ScienceDirect article ‘Scenario-based approach to assess Ho Chi Minh City’s urban development strategies against the impact of climate change’ by Harry Storch and Nigel K. Downes, “The influence of planned urban developments to the year 2025 on future flood risk is seen to be significantly greater than that of projected sea-level rise to the year 2100.”

In short, climate change is part of the bigger picture but the speed with which major developments are going up has had an immediate effect on infrastructure demands and flooding in HCMC.

In 2016, Vietnam in conjunction with the World Bank began a flood prevention project near Saigon that was projected to cost more than USD$400 million to deal with overflow but the project was halted because of site clearance problems. However, there is still hope for positive progress. The ADB (Asian Development Bank) has said it is willing to invest in sewage and drainage systems in Ho Chi Minh City and a collaboration between Royal HaskoningDHV, an engineering consulting firm headquartered in the Netherlands, and Deltares, an independent institute for applied research in the field of water, subsurface and infrastructure, have been brought in to create a comprehensive plan. In the meantime, the density of concrete buildings continues to rise, leaving no space under or above ground for water to escape and sustainable development projects are still a minority in Saigon’s urban sprawl.

Greener Solutions for Dryer Futures in Saigon

Melissa Merryweather, Director of Green Consult Asia the first company based in Vietnam to offer professional consulting services for sustainable development as well as the former Chair of the Vietnam Green Building Council, told #iAMHCMC that “Development was very slow for a long time except at the low-cost, or single-family homes end, but the last 10 years has been extraordinary. We see it elsewhere in Asia, this very short building cycle even for major projects, but it is still quite breathtaking. The problem is that you can’t build that quickly and still build carefully and the macro-planning of roads, transportation, parking, and public spaces has to be incredibly well thought out. Public spaces and infrastructure have not been prioritized in HCMC.”

During the property boom that began in HCMC after Vietnam entered the WTO (World Trade Organisation) in 2007, developers launched their projects on whatever land was available without having much interference from urban planning committees. Some of these new developments, mainly mixed-use retail/residential spaces, have put HCMC on the international map. The Landmark 81 project, officially completed in July of this year, for example, is a source of pride for Vietnam as the 14th tallest building in the world.

However, fighting floods as well as creating a city that is livable, sustainable and economically viable requires a strategy that goes beyond how high the city can build. Especially, when that city has a population of close to 8.5 million and housing is in high demand.

“There is a public interest in all the things that sustainability is about: in healthy living, in a cleaner environment, in controlling climate change. But the developers just see profit margins so far”, Merryweather said. “However, there is some competition at the top to have a green certification so there are a few projects taking that on board, and there are a few developers who want to bring those benefits to people in Saigon. A few.”

Green Consult and KAZE Interior Design Studio can work with clients to integrate sustainable solutions in the development and design process to reduce environmental impact from construction. It is also possible for HCMC’s urban planners to inspire themselves by green initiatives that have worked in other cities. A few include rooftops and parking lots designed to store water in the case of excess rain-flow, permeable pavements, and percolation trenches, which are porous canals used to trap water. In a neighborhood in Seattle, Washington in the US, the stormwater runoff was reduced by 98 percent simply by making the street narrower and placing vegetated swales along the sides of the road. The swales, plant-filled canals, are multipurpose; they collect rainwater runoff as well as improving the visual design, air quality and water quality of the city.

Long-term solutions are still in the planning stages but the question remains - Will HCMC be able to rise to the challenge of creating a more livable city out of necessity? Or will it continue to sink underwater with every passing storm?