Reconstituting past flood events: the contribution of citizen science

Abstract. Information gathered on past flood events is essential for understanding and assessing flood hazard. In this study, we present how citizen science can help retrieving this information, in particular in areas with scarce or no instrumental measurements on past events. The case study is located in Yeumbeul North (YN), Senegal, where flood impacts represent a growing concern for the local community. This area lacks instrumental records on flood extent and water depth as well as information on the chain of causative factors. We developed a framework using two techniques to retrieve information on past flood events by involving two groups of citizens who were present during the floods. The first technique targeted the part of the citizens’ memory, which records information on events, recalled through narratives, whereas the second technique focused on scaling past flood event intensities using different parts of the witnesses’ body. These techniques were used for 3 events, which occurred in 2005, 2009 and 2012. They proved complementary by providing quantitative information on flood extents and water depths, and by revealing factors that may have contributed in aggravating floods for 3 events which occurred in 2005, 2009 and 2012.

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Reconstituting past flood events: the contribution of citizen science

Hydrology and Earth System Sciences ◽

10.5194/hess-24-61-2020 ◽

2020 ◽

Vol 24 (1) ◽

pp. 61-74 ◽

Cited By ~ 2

Author(s):

Bocar Sy ◽

Corine Frischknecht ◽

Hy Dao ◽

David Consuegra ◽

Gregory Giuliani

Keyword(s):

Citizen Science ◽

Local Community ◽

Quantitative Information ◽

Flood Hazards ◽

Flood Events ◽

Flood Impacts ◽

Causative Factors ◽

Different Parts ◽

Water Depths

Abstract. Information gathered on past flood events is essential for understanding and assessing flood hazards. In this study, we present how citizen science can help to retrieve this information, particularly in areas with scarce or no authoritative measurements of past events. The case study is located in Yeumbeul North (YN), Senegal, where flood impacts represent a growing concern for the local community. This area lacks authoritative records on flood extent and water depth as well as information on the chain of causative factors. We developed a framework using two techniques to retrieve information on past flood events by involving two groups of citizens who were present during the floods. The first technique targeted the part of the citizens' memory that records information on events, recalled through narratives, whereas the second technique focused on scaling past flood event intensities using different parts of the witnesses' bodies. These techniques were used for three events that occurred in 2005, 2009 and 2012. They proved complementary by providing quantitative information on flood extents and water depths and by revealing factors that may have contributed to all three flood events.

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Multistep Flood Inundation Forecasts with Resilient Backpropagation Neural Networks: Kulmbach Case Study

Water ◽

10.3390/w12123568 ◽

2020 ◽

Vol 12 (12) ◽

pp. 3568

Author(s):

Qing Lin ◽

Jorge Leandro ◽

Stefan Gerber ◽

Markus Disse

Keyword(s):

Neural Networks ◽

Flood Hazard ◽

Forecast Accuracy ◽

Threshold Value ◽

Flood Inundation ◽

Flood Events ◽

Forecast Performance ◽

Flooding Event ◽

Good Forecast

Flooding, a significant natural disaster, attracts worldwide attention because of its high impact on communities and individuals and increasing trend due to climate change. A flood forecast system can minimize the impacts by predicting the flood hazard before it occurs. Artificial neural networks (ANN) could efficiently process large amounts of data and find relations that enable faster flood predictions. The aim of this study is to perform multistep forecasts for 1–5 h after the flooding event has been triggered by a forecast threshold value. In this work, an ANN developed for the real-time forecast of flood inundation with a high spatial resolution (4 m × 4 m) is extended to allow for multiple forecasts. After trained with 120 synthetic flood events, the ANN was first tested with 60 synthetic events for verifying the forecast performance for 3 h, 6 h, 9 h and 12 h lead time. The model produces good results, as shown by more than 81% of all grids having an RMSE below 0.3 m. The ANN is then applied to the three historical flood events to test the multistep inundation forecast. For the historical flood events, the results show that the ANN outputs have a good forecast accuracy of the water depths for (at least) the 3 h forecast with over 70% accuracy (RMSE within 0.3 m), and a moderate accuracy for the subsequent forecasts with (at least) 60% accuracy.

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Community Flood Impacts and Infrastructure: Examining National Flood Impacts Using a High Precision Assessment Tool in the United States

Water ◽

10.3390/w13213125 ◽

2021 ◽

Vol 13 (21) ◽

pp. 3125

Author(s):

Jeremy R. Porter ◽

Evelyn Shu ◽

Michael Amodeo ◽

Ho Hsieh ◽

Ziyan Chu ◽

...

Keyword(s):

United States ◽

High Resolution ◽

Flood Risk ◽

Local Community ◽

Assessment Tool ◽

Flood Hazard ◽

Past Research ◽

The United States ◽

Social Infrastructure ◽

Flood Impacts

Changing environmental conditions are driving worsening flood events, with consequences for counties, cities, towns, and local communities. To understand individual flood risk within this changing climate, local community resiliency and infrastructure impacts must also be considered. Past research has attempted to capture this but has faced several limitations. This study provides a nation-wide model of community flooding impacts within the United States currently and in 30 years through the use of high-resolution input data (parcel-level), multi-source flood hazard information (four major flood types), multi-return period hazard information (six return periods), operational threshold integration, and future-facing projections. Impacts are quantified here as the level of flooding relative to operational thresholds. This study finds that over the next 30 years, millions of additional properties will be impacted, as aspects of risk are expected to increase for residential properties by 10%, roads by 3%, commercial properties by 7%, critical infrastructure facilities by 6%, and social infrastructure facilities by 9%. Additionally, certain counties and cities persistently display impact patterns. A high-resolution model capturing aspects of flood risk as related to community infrastructure is important for an understanding of overall community risk.

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An analysis of Italian damage data to economic activities

10.5194/egusphere-egu21-10086 ◽

2021 ◽

Author(s):

Marta Galliani ◽

Francesca Carisi ◽

Alessio Domeneghetti ◽

Giovanni Menduni ◽

Daniela Molinari ◽

...

Keyword(s):

Critical Role ◽

Flood Damage ◽

Flood Events ◽

Economic Activities ◽

Commercial Activities ◽

Flood Impacts ◽

Damage Modelling ◽

Damage Data ◽

Observed Damage

<p>The study of flood impacts on the different sectors that compose the built environment and the society is crucial to implement actions of prevention, mitigation, and cautious planning. In such a context, the sector of businesses assumes a critical role, both for its importance for the wellbeing of the society and because of the high losses it suffers in case of inundations. Nevertheless, flood damage modelling to businesses is still a challenging task: the large number of different commercial activities, their specific geographical and economic contexts and the few observed damage data are just some of the reasons for that. In Italy, for example, a shared methodology to assess damage to enterprises is not present; building knowledge about types and dimensions of impacts of flood events to economic activities is then even more impelling. This contribution presents the analysis of about a thousand observed damage records regarding industrial and commercial activities, collected by four research groups after different flood events in Italy: the inundation occurred in the town of Lodi (Lombardia Region) in 2002, the one in Sardegna Region in 2013, and the floods caused in the Emilia-Romagna Region by Secchia (2014) and Enza (2017) Rivers. Data retrieved from the local and regional authorities responsible for damage compensation present different levels of detail and aggregation, according to the case study investigated. In all cases, they refer to the direct damage only and, for each case study, they have been first organised according to the activity types (e.g. trade, manufacturing, construction, finance) and per affected components: i.e. structure, equipment and stock. Data analysis has been led by some questions, we identified as key to start developing knowledge for damage modelling:&#160; are there similarities in the different case studies? Which are the more affected business sectors in case of flood? Which component suffers the highest damage among structure, equipment, and stock? Is there an empirical trend of damage with hazard parameters? Results were first compared with the socio-economic context of the affected area, to have a first confirmation of data quality and reliability; then, the analysis focused on searching information and relationships between damage and activity type, activity dimension and water level. Results support the identification of the more vulnerable elements within the business sector, orienting modellers&#8217; and decision-makers&#8217; choices.</p>

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Flood Hazard Assessment Based on Analysis of Geomorphic Flood Index and History of Flood Events (Case Study in Kemuning Watershed, Sampang)

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/366/1/012033 ◽

2019 ◽

Vol 366 ◽

pp. 012033 ◽

Cited By ~ 1

Author(s):

P C Nugroho ◽

D Sutjiningsih ◽

L Kurniawan

Keyword(s):

Hazard Assessment ◽

Flood Hazard ◽

Flood Events ◽

Flood Hazard Assessment ◽

History Of ◽

Flood Index

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Environment and atmosphere of night tourism based on the local wisdom: A case study of Berastagi

Talenta Conference Series Energy and Engineering (EE) ◽

10.32734/ee.v3i1.868 ◽

2020 ◽

Vol 3 (1) ◽

Author(s):

Selly Veronica ◽

Nurlisa Ginting ◽

AmyMarisa

Keyword(s):

Field Observation ◽

Local Community ◽

Tourism Development ◽

Primary Data ◽

Tourist Destination ◽

Innovative Strategy ◽

Depth Interview ◽

Social Environmental ◽

Descriptive Method

Night tourism development comes up as an innovative strategy for tourism development in this current intense competition. There are four main elements in night tourism, namely economic, social, environmental, and night atmosphere. Berastagi is the most popular tourist destination in Karo Regency, Sumatera Utara, Indonesia, which already have night tourism destination but unfortunately undeveloped yet. Night tourism development in Berastagi must be with the local wisdom approach to maximize its benefit. Karonese as the majority ethnic of the local community in this area potential to be developed on its night tourism. This paper only analyzes the environmental and night atmosphere aspects in Berastagi’s night tourism, which based on local wisdom. Qualitative primary data from field observation and depth interview results have been analyzed by using the descriptive method. The study shows that involving local wisdom in developing the environment and night atmosphere can give the typical identity for the night tourism in Berastagi.Night Tourism

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Kelembagaan Masyarakat dan Struktur Agraria serta Keberlanjutan Sumberdaya Alam di Kawasan Capa

Agrotek ◽

10.30862/agt.v2i3.468 ◽

2018 ◽

Vol 2 (3) ◽

Author(s):

Mecky Sagrim

Keyword(s):

Natural Resources ◽

Local Community ◽

Property Right ◽

Local Institutions ◽

Group Property ◽

Young Shoot ◽

Agrarian Structure

Aim of the research as follows: (1) inquisitive about variation of laws in regulating agrarian resources use, (2) function of traditional law in regulation at used of natural resources and related with existence on natural preservation-in formal law, and (3) inquiring influence outsider intervention to local institutions with the agrarian structure and relationship between expectation agrarian conflict. The unity of the study is Arfak community-as much as local community- was that administrative limited seatle in certain locations around natural preservation area of the Arfak Mountain. The trategy of the research is case study, while analysis of the data with qualitative manner. Result of the research is in the locations study beside property right of local community and movement of Arfak community from high land include at the resettlement programme. Not a problem related with economic subsistence with economic un-security because group property right community give free to the movement community for use to agriculture developing. For developing concept of forest sustainable as nit side to one side, income several NGO as well as role as institution relationship (young-shoot autonomy) for accommodation importance various party supra-village in relationship with existence natural preservation area of the Arfak Mountain and the party of local community in related of security in economic subsistence.

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Multi-Criteria Decision Making for Vulnerability Mapping of Flood Hazard: A Case Study of Pune City

10.21523/gcj5.18020105 ◽

2019 ◽

Vol 2 (1) ◽

pp. 41-52

Author(s):

Nitin Mundhe

Keyword(s):

Decision Making ◽

Flood Hazard ◽

Geographical Information ◽

Multi Criteria Decision Making ◽

Flood Hazards ◽

Very High Frequency ◽

Flood Vulnerability ◽

Natural Risk ◽

The Town

Floods are natural risk with a very high frequency, which causes to environmental, social, economic and human losses. The floods in the town happen mainly due to human made activities about the blockage of natural drainage, haphazard construction of roads, building, and high rainfall intensity. Detailed maps showing flood vulnerability areas are helpful in management of flood hazards. Therefore, present research focused on identifying flood vulnerability zones in the Pune City using multi-criteria decision-making approach in Geographical Information System (GIS) and inputs from remotely sensed imageries. Other input data considered for preparing base maps are census details, City maps, and fieldworks. The Pune City classified in to four flood vulnerability classes essential for flood risk management. About 5 per cent area shows high vulnerability for floods in localities namely Wakdewadi, some part of the Shivajinagar, Sangamwadi, Aundh, and Baner with high risk.

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A Conflict between Traditional Flood Measures and Maintaining River Ecosystems? A Case Study Based upon the River Lærdal, Norway

Water ◽

10.3390/w13141884 ◽

2021 ◽

Vol 13 (14) ◽

pp. 1884

Author(s):

Ana Juárez ◽

Knut Alfredsen ◽

Morten Stickler ◽

Ana Adeva-Bustos ◽

Rodrigo Suárez ◽

...

Keyword(s):

Remote Sensing Data ◽

Freshwater Ecosystems ◽

River Channel ◽

Flood Mitigation ◽

Mitigation Measures ◽

Flood Events ◽

Protection Measures ◽

River Ecosystems ◽

Hydraulic Models

Floods are among the most damaging of natural disasters, and flood events are expected to increase in magnitude and frequency with the effects of climate change and changes in land use. As a consequence, much focus has been placed on the engineering of structural flood mitigation measures in rivers. Traditional flood protection measures, such as levees and dredging of the river channel, threaten floodplains and river ecosystems, but during the last decade, sustainable reconciliation of freshwater ecosystems has increased. However, we still find many areas where these traditional measures are proposed, and it is challenging to find tools for evaluation of different measures and quantification of the possible impacts. In this paper, we focus on the river Lærdal in Norway to (i) present the dilemma between traditional flood measures and maintaining river ecosystems and (ii) quantify the efficiency and impact of different solutions based on 2D hydraulic models, remote sensing data, economics, and landscape metrics. Our results show that flood measures may be in serious conflict with environmental protection and legislation to preserve biodiversity and key nature types.

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