Territorial dynamics of spatial growth in Kathmandu Valley, Nepal: understanding geographical notion of urban sustainability

Urbanization is a continuous socio-spatial process which generates territorial dynamics. The rate, pace and magnitude of urbanization differs from one urban area to another. The current study is an attempt to assess level of urbanization through exploring the direction and magnitude of spatial and population growth and foresee future urban growth of eighteen municipalities in Kathmandu Valley based on land cover/ use data from 2001 to 2021. The study was carried out in three steps: i) spatio-temporal change in land cover land use, ii) population growth and migration trend, and iii) built-up growth modeling using Cellular-Automata-Markov method with thirteen input factors. The findings show that built-up growth is linear which increased from 9% in 2001 to 34.6% in 2021. The calculated correlation coefficient value for migration and population growth rate between 2011 and 2021 indicate a statistically significant relationship. Temporal variation of migrated population adhered to spatial variation. The growth modeling exhibit built-up area increase by 40% in 2031 reaching to 67% in 2051. Territorial dynamics of urbanization is prominent. Among oldest and most urbanized units, Kathmandu and Bhaktapur are entering the counter-urbanization stage whereas Madhyapur-thimi, Lalitpur and Kirtipur are sub-urbanizing. Remaining thirteen are urbanizing at different level. Out of 18 municipalities, ratio between land consumption (LCR) rate and population growth rate (PGR) is increasing in 10 municipalities while decreasing in 6 and negative in 2 municipalities (Kathmandu Metropolitan and Bhaktapur). Such variation urges local government to regulate efficient land use planning by promoting compact densities in new development areas. An imprint of increasing LCR and LCRPGR contest the urban sustainability with decreasing compactness and low densification. The study concludes that the apparent variation in level of urbanization together with imminent territorial dynamics points to differential policy and planning requirement at micro spatial unit.