The impacts of flooding on well-being and the role of ecosystem-based adaptation

Published: 9th August 2018 15:41Last Updated: 13th August 2018 10:21
Photo: René Arnold

The problem of flooding

Floods are one of the most devastating disasters, especiallyin Asia. Moreover, it is often the case that poorest in society are the most vulnerable, as they live in the most threatened locations and struggle to cope with the impacts due to income, political, and social constraints. This can be compounded by the observation that developing countries are particularly threatened by flooding because of their limited capacity to prevent and absorb disaster impacts. Moreover, the future threat from flooding is likely to increase due to the effects of climate change changing flood patterns and rapid urbanization placing more people in harm’s way.

Women present one of the groups in society that are particularly vulnerable to the impacts of flooding, because they commonly experience disadvantages in social, cultural, economic and political domains as well as legal status and opportunities. These socio-cultural circumstances can even lead to higher mortality rates among women during floods, and higher poverty rates due to more unemployment and the lack of basic rights. Moreover, women tend to face more psychological stress during and after a disaster due to the women’s caretaker role as part of the family. This difference between women and men in terms of disaster impacts is especially important when it comes to building more resilient communities and it has been recognized as a fundamental part of the United Nation’s Sustainable Development Goals (SDGs) 5 (Gender equality), 10 (Reduced inequalities) and 13 (Climate Action).

Currently, the main focus of flood management in many regions within Asia is on structural measures, such as dikes or reservoirs. However, these measures are often associated with negative impacts on the environment, on which the especially poor and vulnerable communities depend. A wider and more inclusive method of limiting flood impacts is required, particularly in order to meet the Sustainable Development Goals. Ecosystem-based Adaptation (EbA, see Box 1) can prove to be an inclusive complementary measure to the structural measures. EbA strategies are more inclusive to vulnerable groups, whose livelihoods directly depend on natural resources, and make it a promising means to strengthen their position by offering multiple benefits (see here). These multiple benefits provided by EbA measures are how EbA contributes towards meeting the Sustainable Development Goals by increasing resilience (Box 2).

The negelected impacts of flooding

Floods impact societies in various ways, ranging from the loss of life, injuries and mental health effects, to the destruction of assets (see Box 3). However, despite the growing numbers of people affected by flooding, there is little acknowledgement of the whole range of impacts that can occur (see Box 3). There has been an overwhelming focus on assessing the physical or tangible impacts of flooding. Much less is known about the intangible or well-being impacts of flooding, even though these can be substantial. Since a speedy recovery is a key aspect of resilience, we seek to address that concern through the ResilNam project. Better insights and management of this aspect are especially important for areas in which floods occur frequently. An incomplete recovery could result in a vicious cycle of well-being losses unless those affected receive external help to recover.

Approach

In order to study these well-being impacts to gain a better understanding of the total impact of flooding on those affected,we use survey data from flood-prone households inThua Thien Hue, Vietnam. Thua Thien Hue is a coastal province located in central Vietnam (see Figure 1), where ~1.3 million people live (~25% live in Hue city). Hue city was the national capital and seat of Nguyen Dynasty emperors until 1945 and is a UNESCO world heritage site. An important feature of the province is the Huong River that flows through Hue city into the Tam Giang Lagoon and then into the Pacific. The Huong River and the lagoon provide water for the provincial capital of Hue and are the lifelines for many poor and vulnerable people, who directly depend on their natural resources. The province has been repeatedly affected by severe floods in the past decades, as floods occur from rivers, heavy rainfall, and the sea. The last flood was in early
November 2017. Across the province over 160,000 households were affected. Typhoon Damray is estimated to have caused ~110 deaths and a monetary loss of ~US$650 million across Vietnam and the Philippines.

The impacts of floods on well-being are substantial but can be mitigated by EbA

From our survey data we produce the results presented in Table 1, which shows the monetary equivalent of subjective well-being (SWB) losses due to flooding. This monetary estimate is derived from finding the amount of monetary compensation that is needed to off-set the well-being loss from flooding. We present these values in monetary terms (% of annual income) at the household level to show how large these subjective or non-physical impacts are, and that they should not be excluded from flood risk management decision making. This is important as we know that often the intangible impacts of flooding can be larger than the tangible
impacts.

Table 1 shows that the initial drop in SWB immediately after a flood event is equivalent to up to ~300% of annual income in immediate compensation. This shows that the welfare impact of floods is substantial. While a recovery of SWB occurs over time, we find that even 5 years after a flood, the welfare impact still equals a loss that is the equivalent of 40% to 86% of annual income in long-run compensation. The overall welfare losses are substantially larger for women after this period of time (by about 20 to 29 percentage points), indicating a gender-gap in recovery. Moreover, we can see a large potentially longlasting increase in welfare if EbA measures
are employed and maintained over the long-term. This increase can equal up to 152% of annual income and is larger for women, whose livelihood is often more directly linked to local ecosystems.