The value of water is about much more than its price – water has enormous and complex value for our households, culture, health, education, economics and the integrity of our natural environment. If we overlook any of these values, we risk mismanaging this finite, irreplaceable resource.

Today, access to water is under extreme threat from a growing population, increasing demands of agriculture and industry, and the worsening impacts of climate change. The sustainable and efficient use of water is critical in building resilience to climate change, and adapting to its impacts will help to protect health and save lives.

Floods for example are already the most frequent natural disaster globally and cause more damage than any other weather or non-weather related event. Yet, flood-related damages are expected to grow, driven by urbanisation, land use changes and changes in climate patterns.

Through the Australian Water Partnership (AWP), the Australian Government with the World Bank has been supporting an initiative to identify, evaluate and realise the benefits associated with Nature-based Solutions (NbS) for integrated urban flood management in the Mekong region.

NbS is defined by the International Union for Conservation of Nature as “actions to protect, sustainably manage, and restore natural or modified ecosystems, that address societal challenges effectively and adaptively, simultaneously providing human well-being and biodiversity benefits”.

Increasing usage of NbS in cities in the Mekong region relies on building a strong business case, which in turn involves quantifying the associated benefits and comparing them with conventional approaches. To progress this goal, AWP partners—the Cooperative Research Centre for Water Sensitive Cities (CRCWSC) and the International Centre for Environmental Management (ICEM)—are carrying out detailed case studies in two selected countries: Thailand and Vietnam.

Thailand is one of the world’s top 15 countries with populations exposed to river floods (Dilley et al., 2005). Similarly, water-related natural disasters affect more than 70 percent of Vietnam’s population, making it one of the most hazard-prone countries in the world.

On their own, conventional flood management solutions may not respond to these challenges effectively. NbS offers cost-effective and sustainable solutions for urban flood management, and also provide additional benefits to people and the environment. It can also be faster to deliver, involve lower technology requirements, and can be flexibly implemented as standalone measures, or as hybrid solutions together with grey engineering.

“The Valuing the Benefits for Nature-based Solutions for Integrated Urban Flood Management program provides policymakers and professionals with an alternative approach for effective and sustainable water management. The concept of NbS is getting more and more attention in Thailand,” said Ms Chompunut Songkhao, an Environmental Official at the Climate Change Management and Coordination Division of the Office of Natural Resources and Environmental Policy and Planning.

CRCWSC and ICEM have been working in close cooperation with national government agencies to demonstrate the integrated urban flood management process and support the application of the Investment Framework For Economics of Water Sensitive cities and supporting tools. The tools were successfully trialled by CRCWSC throughout Australia and in several cities in China and are being applied to four case study sites in Vietnam and Thailand.

After initial selection and scoping, in parallel with a programme of capacity building, NbS concepts for each site are now being developed with strong input from national partners to ensure locally appropriate delivery. Concepts being explored include:

1. Tam Bình Park, Thủ Đức district, Ho Chi Minh City, Vietnam: A multifunctional urban swamp forest for flood mitigation with stormwater managed aquifer recharge and a subsurface wetland to treat wastewater before conveyance to the drainage system;
2. Phu Quoc island, Duong Dong catchment, Vietnam: A constructed wetland park to provide water regulation and stormwater harvesting, as well as serving as an ecotourism attraction;
3. Sukhumvit District, Bangkok, Thailand:Precinct scale NbS to enhance Benjakitti Park’s redevelopment into a multi-functional wetland as well as small scale NbS (such as stormwater planter boxes and green roofs/walls) to the high density area north of the park;
4. Sukhumvit Road, Rayong, Bangkok, Thailand: Urban canyons to support urban cooling.

Project partners review the Phu Quoc Island concept

Once the concepts have been finalised, the project team will conduct the economic valuation to identify and quantify the costs and benefits of the interventions, considering the full range of market and non-market benefits. Together with consideration of appropriate financing and investment models, and the engagement of national champions, a clear pathway towards implementation at scale emerges.

Mr Ben Furmage, Project Leader and Chief Executive of CRCWSC said, “The level of engagement from Thai and Vietnamese colleagues, AWP and the World Bank has been invaluable in bringing together local knowledge and international experience as we build business cases for hybrid NbS and conventional solutions that respond to local priorities and deliver lasting value.”

For more information, see the project summary: Valuing the benefits of nature-based solutions to integrated urban flood management in Thailand and Vietnam.

Feature photo: Chulalongkorn University Centenary Park, a successful example of integrated urban flood management design using Nature-based Solutions (credit: LANDPROCESS)