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Considering the increasing disaster risks, vulnerability and reduced resilience across Himalayas due to urban sprawling, our study attempts to understand the crucial environmental concerns in the valley town of Dehradun. We assessed the long-term risks due to the rise in population density, changing land use patterns, land surface temperature, groundwater shortage, air pollution concerns, vegetation loss and concretization using remote sensing tools. Results reveal the deleterious impact of urban sprawling affecting different wards of the city, with the burgeoning population pressure in the central part of the city (200 people per hectare (pph)) while, peripheral areas have lesser pressure (4 pph) but projected to rise. Loss of vegetation for development across the city has resulted in insufficient and unequal distribution of green spaces. The builtup area increased from 23.63 to 59.78 % after the city became the state capital has led to the increased heat islands and surface temperature (21.23–25.53 °C). Depleting groundwater levels in erstwhile water sufficient wards of Raipur (01), Shastradhara (02) and Adhoiwala N (28) is alarming. Increasing air pollutants (P.M.10, SO 2 and NO 2) and the risk of urban floods are severe for 10 wards. Dehradun city seems to be at tipping point about to cross its bearing capacity, any additional pressure may have serious repercussions for city residents. City municipal corporation along with diverse stakeholder groups need to mainstream Nature based Solutions, designing and implementing ward specific customized solutions for addressing societal challenges according to Sendai Framework for Disaster Risk Reduction and the UN SDG 11. [ABSTRACT FROM AUTHOR]

Unplanned urbanization in developing cities has led to haphazard development, increasing disaster risks in densely populated areas. Despite being more disaster-prone, these dense settlements often lack essential emergency services. Delivering emergency services requires a high-resolution geodatabase of minor roads and their attributes, such as road width. Such information can be a crucial input for quantifying emergency vehicles (EVs) access in an area. To the best of our knowledge, no research has addressed this problem statement, making this paper the first to propose quantifying road width and using it to develop EVs accessibility maps. We propose a two-stage process to achieve these goals. In the first stage, we designed a deep neural network (DNN) to accurately organize built-up features, including minor roads using true-colour high-resolution satellite imagery of Pleiades-1A for Mumbai. In the second stage, we propose an algorithm to calculate road width and then compare it with EVs dimension (width) details to develop high-resolution accessibility maps. The model classified features with around 91.88% accuracy along with 90% Kappa coefficient, while the classification accuracy of minor roads in informal settlements was about 85.80%. We found that informal settlements have much less access to various EVs compared to formal settlements due to mixed signatures. The outcomes presented in this paper can be used as a decision-making tool to develop a geodatabase of road widths and EVs accessibility maps for efficient resource planning, which can ultimately lead to the development of disaster-resilient cities. • Extraction of minor-roads in dense informal settlements using Deep Learning (DL). • Algorithm to estimate road width from classified imagery. • Generation of high-resolution Emergency Vehicle (EV) accessibility maps for Mumbai, India. [ABSTRACT FROM AUTHOR]

Large urban agglomerations in Sub-Saharan Africa such as Accra face multiple vulnerabilities due to overlapping risks. These include everyday risks related to poor quality water and sanitation, to city level air, water and industrial pollution risks and vulnerabilities to natural disasters such as floods, earthquakes, storms and pandemics. Some of the bio-climatic disasters may be amplified by climate change. The paper argues that the complexity of everyday risks and associated health conditions suffered principally by the poor are interconnected with disaster risk. It examines these inter-relationships in the context of the cholera pandemic of 2014 and the 2015 flood disaster events, as city-wide events which affected both the poor and the wealthy. The paper reflects on the implications of these events - which are to a large extent socially constructed - for thinking about everyday and disaster risk in an urban context, and for policies to address multiple sets of overlapping risks. [ABSTRACT FROM AUTHOR]