Effectiveness of Nature-Based Solutions for Mitigating the Impact of Pluvial Flooding in Urban Areas at the Regional Scale

Abstract

Pluvial flooding causes significant damage in urban areas worldwide. The most common approaches to mitigating these impacts at regional scales include structural measures such as dams, levees and floodways. More recently, the use of nature-based solutions (NBS) is receiving increasing attention, as such approaches are more adaptive than structural measures and have a number of potential co-benefits (e.g., improvements in water quality and amenity). As NBSs are generally applied at house or block scales in urban areas, their potential for reducing the impacts of urban flooding at the regional scale are unknown. We introduce an approach that enables the potential of using portfolios of NBSs to reduce the impact of urban flooding to be assessed at the regional scale. This approach enables the most suitable locations for such portfolios of NBSs to be identified, as well as their effectiveness to be modeled at spatial resolutions that are commonly used for regional planning studies. The approach is applied to a case study area to the north of Adelaide, South Australia, with results obtained suggesting that there is significant potential for using strategically placed portfolios of NBSs to reduce the impact of pluvial flooding in urban areas at the regional scale.

Potential of Decentral Nature-Based Solutions for Mitigation of Pluvial Floods in Urban Areas—A Simulation Study Based on 1D/2D Coupled Modeling

“…Several modeling studies have investigated the effect of NBSs on flood reduction [16,[22][23][24][25][26][27][28]. The study areas varied in scale (regional, city, or catchment), topography, drainage system capacity, and infiltration characteristics of the soil.…”

“…In many studies, researchers simulated only one scenario with different combinations of NBS types and compared them to the base model without an NBS [16,[22][23][24]. This approach makes it impossible to quantify the effect of individual NBS types on flood reduction.…”

Toward urban-rural linkage development: contribution of climate-adaptive agroecology in the lower Chao Phraya River Basin, Thailand

“…Strenuous efforts for countermeasures of flood protection after the 2011 megaflood include the building and non-building measures under the largescale nature-based solutions (NBS) for flood mitigation. These measures involve flood protection systems, including dikes along the canals and polders, the drainage systems that involve canals, pump stations, regulators, and water gates, as well as waterretention areas, and the adjustment of crop cultivation calendar for the farmers in the water-retention fields (Ghozali et al, 2016;Prabnakorn et al, 2021;Hamers et al, 2023;Penny et al, 2023).…”