Improving Urban Flood Resilience under Climate Change Scenarios in a Tropical Watershed Using Low-Impact Development Practices

Abstract. As China is urbanized, flooding has become a regular feature in major cities. Assessing potential urban flood risks under climate change has become crucial for better managing such risks given the severity of the devastating disasters (e.g., the current 2016 flooding across China). Although the impacts of future climate change on urban flood risks have been investigated in many existing studies, the effects of both climate mitigation and adaptations have rarely been accounted for in a consistent framework. In this study, we assess the benefits of (1) avoided greenhouse gas (GHG) emissions and (2) adapting drainage systems on urban flood risks within the context of global warming through a case study in the Northern China. The urban drainage model, Storm Water Management Model (SWMM), was employed to simulate urban floods under current conditions and two feasible adaptation scenarios (i.e., pipe enlargement and low impact development), driven by bias-corrected meteorological forcing from five general circulation models (GCMs) in the Coupled Model Intercomparison Project Phase 5 (CMIP5) archive Based on the results, the volume of urban floods is projected to increase by 52 % in the period of 2020–2040 when compared to that in 1971–2000 under the business-as-usual scenario (i.e., Representative Concentration Pathways (RCP) 8.5). The magnitudes of urban floods are found to increase nonlinearly with changes in precipitation intensity, and highest risks associated with floods with smaller return periods below 10 years are identified. Despite the high level of uncertainty, it is obvious that avoided greenhouse emissions will be beneficial in terms of reducing risks associated with urban floods. On average, the magnitude of projected urban floods under RCP 2.6 is 13 % less than that under RCP8.5, demonstrating the importance of global-scale efforts on GHG emission reduction in regulating local to regional hydrometeorological responses. Moreover, the two feasible adaptation scenarios are shown to be able to further reduce risk associated with floods effectively. This study highlights the importance of accounting for local climate adaptation efforts in assessing urban flood risks under a changing climate.

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Performance of Lot-Level Low Impact Development Technologies Under Historical and Climate Change Scenarios

Journal of Hydro-environment Research ◽

10.1016/j.jher.2021.07.004 ◽

2021 ◽

Author(s):

Albert Z. Jiang ◽

Edward A. McBean

Keyword(s):

Climate Change ◽

Low Impact Development ◽

Climate Change Scenarios

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Assessing Hydrological Effects of Bioretention Cells for Urban Stormwater Runoff in Response to Climatic Changes

Water ◽

10.3390/w11050997 ◽

2019 ◽

Vol 11 (5) ◽

pp. 997 ◽

Cited By ~ 9

Author(s):

Mo Wang ◽

Dongqing Zhang ◽

Siwei Lou ◽

Qinghe Hou ◽

Yijie Liu ◽

...

Keyword(s):

Climate Change ◽

Low Impact Development ◽

Climatic Changes ◽

Climate Change Scenarios ◽

Multiple Parameters ◽

Planning And Design ◽

Urban Stormwater Runoff ◽

Peak Runoff ◽

Slight Growth

An investigation into the effectiveness of bioretention cells (BCs) under potential climatic changes was conducted using representative concentration pathways. A case study of Guangzhou showed changes in peak runoff in climate change scenarios, with obvious growth in RCP8.5 and slight growth in RCP2.6. The performance of BCs on multiple parameters, including reduction of runoff volume, peak runoff, and first flush, were examined in different design storms using a hydrology model (SWMM). The effectiveness of BCs varied non-linearly with scale. Their performance fell by varying amounts in the various scenarios. BCs could provide sufficient effects in response to short-return-period and short-duration storms, but the performance of BCs decreased with heavy storms, especially considering climate change. Hence, BCs cannot replace grey infrastructure but should be integrated with them. The method developed in this study could be useful in the planning and design of low impact development in view of future climate changes.

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Flood4castRTF: A Real-Time Urban Flood Forecasting Model

Sustainability ◽

10.3390/su13105651 ◽

2021 ◽

Vol 13 (10) ◽

pp. 5651

Author(s):

Michel Craninx ◽

Koen Hilgersom ◽

Jef Dams ◽

Guido Vaes ◽

Thomas Danckaert ◽

...

Keyword(s):

Climate Change ◽

Real Time ◽

Model Building ◽

Change Scenario ◽

Climate Change Scenarios ◽

Urban Flood ◽

Flood Modelling ◽

Physically Based ◽

Physically Based Models ◽

Modelling Approach

Worldwide, climate change increases the frequency and intensity of heavy rainstorms. The increasing severity of consequent floods has major socio-economic impacts, especially in urban environments. Urban flood modelling supports the assessment of these impacts, both in current climate conditions and for forecasted climate change scenarios. Over the past decade, model frameworks that allow flood modelling in real-time have been gaining widespread popularity. Flood4castRTF is a novel urban flood model that applies a grid-based approach at a modelling scale coarser than most recent detailed physically based models. Automatic model set-up based on commonly available GIS data facilitates quick model building in contrast with detailed physically based models. The coarser grid scale applied in Flood4castRTF pursues a better agreement with the resolution of the forcing rainfall data and allows speeding up of the calculations. The modelling approach conceptualises cell-to-cell interactions while at the same time maintaining relevant and interpretable physical descriptions of flow drivers and resistances. A case study comparison of Flood4castRTF results with flood results from two detailed models shows that detailed models do not necessarily outperform the accuracy of Flood4castRTF with flooded areas in-between the two detailed models. A successful model application for a high climate change scenario is demonstrated. The reduced data need, consisting mainly of widely available data, makes the presented modelling approach applicable in data scarce regions with no terrain inventories. Moreover, the method is cost effective for applications which do not require detailed physically based modelling.

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Research Progress of Urban Floods under Climate Change and Urbanization: A Scientometric Analysis

Buildings ◽

10.3390/buildings11120628 ◽

2021 ◽

Vol 11 (12) ◽

pp. 628

Author(s):

Qiu Yang ◽

Xiazhong Zheng ◽

Lianghai Jin ◽

Xiaohui Lei ◽

Bo Shao ◽

...

Keyword(s):

Climate Change ◽

Scientific Knowledge ◽

Global Climate ◽

Low Impact Development ◽

Research Progress ◽

Future Research ◽

Scientometric Analysis ◽

Knowledge Mapping ◽

Urban Floods ◽

Urban Flood

Urban floods research has been attracting extensive attention with the increasing threat of flood risk and environmental hazards due to global climate change and urbanization. However, there is rarely a comprehensive review of this field and it remains unclear how the research topics on urban floods have evolved. In this study, we analyzed the development of urban floods research and explored the hotspots and frontiers of this field by scientific knowledge mapping. In total, 3314 published articles from 2006 to 2021 were analyzed. The results suggest that the number of published articles in the field of urban floods generally has an upward trend year by year, and the research focus has shifted from exploring hydrological processes to adopting advanced management measures to solve urban flood problems. Moreover, urban stormwater management and low impact development in the context of climate change and urbanization have gradually become research hotspots. Future research directions based on the status and trends of the urban floods field were also discussed. This research can not only inspire other researchers and policymakers, but also demonstrates the effectiveness of scientific knowledge mapping analysis by the use of the software CiteSpace and VOSviewer.

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Urban flood risk analysis of buildings using HEC-RAS 2D in climate change framework

H2Open Journal ◽

10.2166/h2oj.2021.111 ◽

2021 ◽

Author(s):

R. Madhuri ◽

Y. S. L. Sarath Raja ◽

K. Srinivasa Raju ◽

Bonagiri Sai Punith ◽

Kondisetti Manoj

Keyword(s):

Climate Change ◽

Risk Analysis ◽

Capital Investment ◽

Adaptation Strategies ◽

Climate Change Scenarios ◽

Urban Flood ◽

Flood Depth ◽

Ideal Situation ◽

Change Framework ◽

Analysis System

Abstract The present study aims to assess flood depth, building risk analysis, and the effectiveness of various flood adaptation strategies to attenuate building risk caused by urban floods in climate change scenarios. A framework is proposed where a hydraulic model, Hydrologic Engineering Center's-River Analysis System 2D (HEC-RAS 2D), is applied for 2-dimensional flood modeling to estimate (a) submerged areas, (b) flood depth, and (c) building risk for extreme events corresponding to two representative concentration pathways (RCPs), 6.0 and 8.5. Greater Hyderabad Municipal Corporation (GHMC), India, is chosen for demonstration. Percentages of buildings in GHMC under high, medium, and low risks for RCP 6.0 are 38.19, 9.91, and 51.9% in the respective order, and these are 40.82, 10.55, and 48.63% for RCP 8.5. Six flood proofing (FP) strategies (S1–S6) are proposed for attenuating building risk along with the required capital cost. The capital investment required for FP to achieve the ideal situation of no risk for all buildings (strategy S6) works out to Rs. 3,740 × 107 and Rs. 3,800 × 107 for RCPs 6.0 and 8.5. It is observed that the effect of adaptation strategies is significant.

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A Study on Implementation of Low Impact Development as an Urban Stormwater Management Technique in Srinagar City: Current Trends, Issues and Challenges

International Journal for Research in Applied Science and Engineering Technology ◽

10.22214/ijraset.2021.37842 ◽

2021 ◽

Vol 9 (8) ◽

pp. 2629-2636

Author(s):

Basrah Bilal

Keyword(s):

Climate Change ◽

Stormwater Management ◽

Low Impact Development ◽

Urban Stormwater ◽

Urban Floods ◽

Urban Flood ◽

Urban Stormwater Management ◽

Flood Impacts ◽

The World ◽

Srinagar City

Abstract: The Severity as well as the frequency of short-duration, but damaging, urban area floods have increased in recent years across the world. Alteration to the urban micro-climate due to global climate change impacts may also exacerbate the situation in the near future. The events of floods have increased in Srinagar city as well over the past decades. Sustainable urban stormwater management using low impact development (LID) techniques, along with conventional urban stormwater management systems, can be implemented to mitigate climate-change-induced flood impacts in Srinagar. In this study, the supposed effectiveness of LIDs in the mitigation of urban flood in Srinagar city is analysed keeping in view their limitations at the same time. A critical research on the success of these techniques in urban flood mitigation planning in Srinagar city is also recommended. On summarising different LID approaches in the world, the results revealed that LIDs can be an efficient method for mitigating urban flood impacts. Most of the LID devices developed so far, however, are found to be effective only for small flood peaks. The major challenges include identification of the best LID practices for the region of interest, efficiency improvements in technical areas, and site-specific optimization of LID parameters. Research and improvements in these areas will allow better mitigation of climate-change-induced urban floods in a cost-effective manner and will also assist in the achievement of sustainable development goals for Srinagar city and will help us to tackle the increasing problems of water logging and floods in the summer capital of Jammu and Kashmir. Keywords: Climate change, Urban floods, stormwater management, Low Impact Development, Srinagar city, Drainage in Srinagar, Pluvial flooding.

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Climate Change Impacts and Flood Control Measures for Highly Developed Urban Watersheds

Water ◽

10.3390/w10070829 ◽

2018 ◽

Vol 10 (7) ◽

pp. 829 ◽

Cited By ~ 11

Author(s):

Carla da Silva ◽

Andre Schardong ◽

Joaquin Garcia ◽

Cristiano Oliveira

Keyword(s):

Climate Change ◽

Flood Control ◽

Climate Models ◽

Climatic Factors ◽

Low Impact Development ◽

Global Climate Models ◽

Control Measures ◽

Mitigation Measures ◽

Climate Change Scenarios ◽

Idf Curves

Flooding and overflow are recurring problems in several Brazilian cities, which usually face disorderly development. The causes vary, and include increased impervious surface areas, deficiency/inefficiency of drainage structures and lack of maintenance, siltation of rivers, channel obstructions, and climatic factors. In this paper, we present an analysis of mitigation measures to minimize flooding in a watershed located in the core of the city of São Paulo, the biggest city with the highest gross domestic product (GDP) in Brazil. Observed rainfall records and existing intensity duration frequency (IDF) curves for the region are used to obtain design storms. To account for climate change, the equidistance quantile matching method for updating IDF curves under climate change, a well-known procedure, was applied to the existing historical data. Several different global climate models (GCMs) and one regional model were applied to obtain and update rainfall design storms. The GCMs and future scenarios used were from Intergovernmental Panel on Climate Change—IPCC Assessment Report 5 (AR5) and two future projections—representative concentration pathway (RCP) 4.5 and 8.5. Spatially distributed reservoirs combined with low-impact development (LID) measures were used to evaluate different design storm scenarios combined with return periods of 25 and 100 years as well as the updated IDF under climate change for RCP 4.5 and RCP 8.5. Results show that the proposed changes to the drainage system can help reduce the risk and damage of flooding. The climate change scenarios, however, impose a significant threat and need immediate attention from city planners and stakeholders.

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