The Benefits of Green Infrastructure (GI) for Flood Damage Reduction

                                                    

 

Green Infrastructure 

                                                        Introduction

Green infrastructure describes using ecological and natural processes to manage water and develop a sustainable and resilient society. According to Newman et al. (2022), the U.S. EPA (Environmental Protection Agency) defines green infrastructure as different technologies, practices, and products that utilize natural systems or engineered strategies that resemble natural processes to improve general environmental quality and offer utility services. Therefore, based on the EPA’s definition, green infrastructure encompasses innovative strategies to reduce the adverse effects of floods.

From the perspective of flood damage reduction, green infrastructure provides various significant benefits for the local governments, which are responsible for assisting the affected communities. For instance, Kousky et al. (2013) argued that green infrastructure strategies impressed local governments as approaches to lowering flood risks and offering different beneficial environmental services. As a result, the presentation focuses on the benefits and cost-effectiveness of green infrastructure to local governments in their various strategies for reducing flood destruction in the communities.

                                            Erosion Control

Large populations, such as in urban areas, trigger natural land movement into impervious surfaces. Furthermore, when it rains heavily in some urban areas, their traditional drainage systems cannot withstand surface runoff, causing flood disasters (Li et al., 2021). According to Li et al. (2021), some regions in urban centers consist of impermeable surfaces, which decrease water infiltration, leading to strengthened erosion in these regions, which transfer pollutants into nearby water bodies, causing water pollution. Therefore, sustainable and practical approaches are needed to address these challenges. Green infrastructure stands out as cheap, sustainable, and effective in controlling erosion: natural features and vegetation incorporated in green infrastructure function as effective erosion control measures. Additionally, vegetation along water sources and flood-prone regions stabilized soil, minimizing erosion and reducing the risk of flash floods.

Floodplain Restoration

Natural floodplains play significant roles in reducing flood risks. For instance, by slowing runoff, they store water, which can be used for different purposes such as irrigation, construction sector, etc. However, different factors contribute to the destruction of floodplains. The ones addressed here are just a few examples. The main key suspect of these factors is urbanization. The conversion of natural floodplain regions for urban development and infrastructure projects minimizes space available for floodwater to spread out and be absorbed. As a result, these activities interrupt the natural flow of water dynamics, leading to increased runoff (Li et al., 2021). Thus, this escalates the adverse effects of floods in such areas. Deforestation and the removal of natural vegetation from floodplains contribute to soil erosion. The loss of vegetation reduces the stability of riverbanks, upsurges sedimentation in rivers, and diminishes the natural buffering capacity of the floodplain.

 Therefore, green infrastructure (GI) is crucial in restoring natural floodplains. For instance, it allows water to naturally spread out over the floodplain during periods of high flow, promoting connectivity between rivers and their floodplains and reestablishing these alluvial plains. Moreover, restoring and creating wetlands within floodplains helps absorb and store floodwaters, reducing downstream flooding. Again, planting and maintaining riparian buffer zones along watercourses help stabilize riverbanks, reduce erosion, and provide a natural barrier that slows down and filters water entering the floodplain. This helps prevent excessive sedimentation and nutrient runoff.

Stormwater Management

Stormwater affects infrastructure, public health, and the environment. These impacts are common in urban areas with impervious surfaces. Stormwater endangers people's lives when it picks up pollutants such as sediment, oil, grease, heavy metals, nutrients, and bacteria from urban surfaces. When this happens, the money local governments spend on addressing public health increases and upsurges the number of patients in public hospitals. For these reasons, green infrastructure is the best approach to help in such circumstances, as researchers such as Newman et al. (2022) noted. Newman et al. (2022) findings indicate that using different landscape performance models to assess the green infrastructure's impacts on pollutant transfer and flood mitigation during floods reduced flood risks and stormwater runoff contaminants and offered practical ways to safeguard vulnerable communities. Green infrastructure strategies, such as permeable surfaces, rain gardens, and green roofs, assist in absorbing and managing stormwater. As a result, this strategy decreases the velocity and volume of runoff during heavy rainfall, leading to mitigating flooding risks.

Cost-effectiveness of Green Infrastructure Strategies

Examining the cost-effectiveness of green infrastructure approaches requires comprehensive consideration of environmental, social, and economic factors. As a result, before local governments decide to implement specific GI practices, it is essential to consider the long-term benefits, sustainability, resilience, and up-front costs of green infrastructure. According to Li et al. (2021), these factors depend on specific GI practices, varying from one strategy to another. Li et al. (2021) investigated the cost-efficiency and effectiveness of GI strategies on surface runoff reduction. In some circumstances, the upfront of implementing green infrastructure practices can be higher than traditional approaches for the same course. However, over time, green infrastructure delivers cost savings in reduced maintenance, lower energy consumption, and increased resilience, making it financially advantageous in the long run.

Moreover, by reducing the load on traditional stormwater systems, green infrastructure leads to cost savings associated with constructing and maintaining pipes, drains, and treatment facilities. Li et al. (2021) found that different GI practices are associated with distinctive cost-saving and benefits. Therefore, local government should consider the benefits of GI practice against its associated cost to implement it.

Conclusion

Findings from these three articles (Newman et al., 2022; Kousky et al., 2913; Li et al., 2021) demonstrated that green infrastructure strategies are related to different benefits, such as floodplain restoration, erosion control, and stormwater management. Green spaces and aesthetically pleasing environments can enhance property values. Furthermore, they are cost-effective. Nonetheless, they require intensive investment, but with time, they save costs compared to traditional systems. It was established that it is fundamental for local governments to consider every GI practice in their disaster management strategies based on its costs and benefits. Using this approach would help local governments understand the best GI practice for every situation to save the lives of people in the community from the adverse effects of floods.

References

Kousky, C., Olmstead, S.M., Walls, M.A., & Macauley, M. (2013). Strategically planning green infrastructure: Cost-effective land conservation in floodplain. Eviron. Sci. Technol., 47, 3563–3570. dx.doi.org/10.1021/es303938c |

Li, F., Chen, J., Engel, B.A., Liu, Y., Wang, S., & Sun, H. (2021). Assessing the effectiveness and cost efficiency of green infrastructure practices on surface runoff reduction at an urban watershed in China. Water, 2021, 13(24), 1-19. https://dx.doi.org/10.3390/w13010024

Newman, G., Sansom, G.T., Yu, S., Kirsch, K.R., Li, D., Kim, Y., Horney, J.A., Kim, G., & Musharrat, S. (2022). Sustainability, 14(4247), 1–16. https://doi.org/10.3390/

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