Abstract:
The Narmada river basin is a highly regulated catchment in central India, supporting a
population of over 16 million people. In such extensively modified hydrological systems, the influence
of anthropogenic alterations is often underrepresented or excluded entirely by large-scale hydrological
models. The GlobalWater Availability Assessment (GWAVA) model is applied to the Upper Narmada,
with all major dams, water abstractions and irrigation command areas included, which allows for the
development of a holistic methodology for the assessment of water resources in the basin. The model
is driven with 17 Global Circulation Models (GCMs) from the Coupled Model Intercomparison Project
Phase 5 (CMIP5) ensemble to assess the impact of climate change on water resources in the basin
for the period 2031–2060. The study finds that the hydrological regime within the basin is likely to
intensify over the next half-century as a result of future climate change, causing long-term increases
in monsoon season flow across the Upper Narmada. Climate is expected to have little impact on dry
season flows, in comparison to water demand intensification over the same period, which may lead
to increased water stress in parts of the basin.
