Multihazard Risk Assessment for Planning with Climate in the Dosso Region, Niger

Abstract

International aid for climate change adaptation in West Africa is increasing exponentially, but our understanding of hydroclimatic risks is not keeping pace with that increase. The aim of this article is to develop a multihazard risk assessment on a regional scale based on existing information that can be repeated over time and space and that will be useful during decision-making processes. This assessment was conducted in Dosso (Niger), the region most hit by flooding in the country, with the highest hydroclimatic risk in West Africa. The assessment characterizes the climate, identifies hazards, and analyzes multihazard risk over the 2011–2017 period for each of the region’s 43 municipalities. Hazards and risk level are compared to the intervention areas and actions of 6 municipal development plans and 12 adaptation and resilience projects. Over the past seven years, heavy precipitation and dry spells in the Dosso region have been more frequent than during the previous 30-year period. As many as 606 settlements have been repeatedly hit and 15 municipalities are classified as being at elevated-to-severe multihazard risk. The geographical distribution of the adaptation and resilience projects does not reflect the risk level. A third of the local development plans examined propose actions that are inconsistent with the main hydroclimatic threats.

Assessing and mapping multi-hazard risk susceptibility using a machine learning technique

“…Further, a synthesized multi-hazard probability map supports planners in sustainable development and adaptive management because this map provides homogenized information about different environmental hazards for a specific area 64 . It means that the potential use of hazard evaluation becomes obvious when considering all hazards together, on the basis of which plans and projects can be implemented considering this comprehensive view of a region 59 . From this point of view, a multi-hazard probability map can be used for integrated and comprehensive watershed management and land use planning and, consequently, for the sustainable development of a region.…”

Multi-Hazard Risk Assessment at Community Level Integrating Local and Scientific Knowledge in the Hodh Chargui, Mauritania

“…Contrary to the indications of the Sendai framework (2015) [2], the integration of knowledge is still unusual on a regional scale. The systematic review highlighted that only one assessment out of four published on tropical African regions estimated the probability of flooding or drought [1,3,11,18,19,27]. This is likely to result from poor access to local data.…”

“…However, the risk assessments published on tropical Africa (Table 1) deal with a single hazard at a time, which in 90% of cases, is the flood hazard and, for the remainder, the drought hazard. [7,8,11,[18][19][20][21][22][23][24][25]] Drought [26,27] Meteorological drought -Hydrological drought [27] Probability [1,3,11,18,19,27] Adaptive capacity [1,9,17,18] Evaluation - [1,4,7,11,13,19,21] The published assessments usually follow two approaches. The first approach performs distance assessments through satellite images, digital elevation models, soil maps, precipitations, and stream-flow datasets.…”

“…Although the importance of local knowledge in adapting to climate change [29] is unquestionable and there is a broad consensus regarding the need to combine it with scientific knowledge in risk reduction [30][31][32][33], assessments in tropical Africa which integrate both types of knowledge are still rare [1,3,18].…”

Flood Hazard Scenarios of the Sirba River (Niger): Evaluation of the Hazard Thresholds and Flooding Areas

“…The basin, located between the isohyets 400 and 700 mm, is characterized by a Sahelian semiarid climate. The clime of this area comprised two well-defined seasons, the dry season (October-May) and the rain season (June-September) [33,34]. The Sirba River's hydrology is strongly related to the monsoon season.…”