Growing City and Rapid Land Use Transition: Assessing Multiple Hazards and Risks in the Pokhara Valley, Nepal

Abstract

Pokhara is one of the most naturally beautiful cities in the world with a unique geological setting. This important tourist city is under intense pressure from rapid urbanization and population growth. Multiple hazards and risks are rapidly increasing in Pokhara due to unsustainable land use practices, particularly the increase in built-up areas. This study examines the relationship among urbanization, land use/land cover dynamics and multiple hazard and risk analysis of the Pokhara valley from 1990 to 2013. We investigate some of the active hazards, such as floods, landslides, fire, sinkholes, land subsidence and earthquakes, and prepare an integrated multiple hazard risk map indicating the highly vulnerable zones. Land use and land cover maps from 1990 and 2013 from Landsat images (30 m resolution) have been prepared and analyzed for the spatial dynamics of urbanization and the transition of land use and land cover. In the 23-year period, the built-up area more than doubled from 24.03 km² to 54.20 km². Although the landscape in the urban, peri-urban and rural areas appears to be fragmented, different drivers play pivotal roles in landscape change in these areas. The results provide OPEN ACCESSLand 2015, 4 958 substantial information for establishing innovative action plans for disaster risk management in the valley. Recommendations are made for the most suitable places for future urban expansion in the valley. This study is important for raising awareness among policy makers and other public officials to include multiple hazard risk mitigation in land use policies and plans. Establishing connections between urban expansions, escalating population growth and multiple hazards and risk assessment will also improve in modelling the latent impact of future catastrophes and emergency preparedness.

Urban Expansion Occurred at the Expense of Agricultural Lands in the Tarai Region of Nepal from 1989 to 2016

“…Clearly, beyond localized urban-growth management and land-use zonation in Tarai, the prevention of agricultural loss due to urban growth in Tarai will require national development programmes focused on Nepal's poorer regions to entice would-be economic migrants to remain. Previous studies [29,[34][35][36]59,68] have similarly reported the loss of highly fertile agricultural lands in the different part of Nepal due to urbanization and population pressure, suggesting that our regional observations capture a general trend that is likely to continue, and even intensify, in the absence of any intervention to the contrary.…”

“…Notwithstanding limited localized studies of urban sprawl around individual Nepalese urban centers [18,22,29,[34][35][36][37][38][39], there have been no large scales analyses of Nepalese urban expansion and its implications for land-cover change and agricultural production. In response, this article observes long-term trends in urbanization in the Tarai region and highlights associated underlying socio-economic factors.…”

Rural earthen roads impact assessment in Phewa watershed, Western region, Nepal

“…According to our data, in 2013, Phewa lake covered 3.3 % of the total watershed area. This figure is similar to recently published data, which determined the lake's surface to be 3.96 % in 2013 (Rimal et al, 2015). The capacity of the lake was estimated as 42.18 million m 3 in 1998, and the annual average sedimentation rate in the lake was about 180,000 m 3 (Sthapit and Baila, 1998).…”

Flood Hazard Mapping of a Rapidly Urbanizing City in the Foothills (Birendranagar, Surkhet) of Nepal

“…A "region of interest" (ROI) boundary representing municipality level study area was delineated for the classification. ENVI software was used to stack, subset, and classify the Landsat images via a maximum-likelihood (ML) algorithm [21,37,38]. A supervised approach with the ML-classifier algorithm was applied for the extraction of LULC.…”