Numerical modelling of salt-water intrusion due to human activities and sea-level change in the Godavari Delta, India

• Published in: Hydrological sciences journal Vol. 47; no. sup1; pp. S67 - S80
• Main Author: BOBBA, A. GHOSH
• Format: Journal Article
• Language: English
• Published: Taylor & Francis Group 01.08.2002
• Subjects: Brackish; climate change impacts; delta du Godavari; Godavari Delta; impacts du changement climatique; impacts du changement du niveau de la mer; impacts of sea-level change; Inde; India; intrusion d'eau saline; modèle SUTRA; modélisation numérique; numerical modelling; salt water intrusion; SUTRA model; India, Andhra Pradesh, Godavari Delta; ISW, India, Andhra Pradesh, Godavari Delta
• ISSN: 0262-6667; 2150-3435
• DOI: 10.1080/02626660209493023

The effects of human activities and sea-level changes on the spatial and temporal behaviour of the coupled mechanism of salt-water and freshwater flow through the Godavari Delta of India were analysed. The density driven salt-water intrusion process was simulated with the use of a SUTRA (Saturated-Unsaturated TRAnsport) model. Physical parameters, initial heads, and boundary conditions of the delta were defined on the basis of available field data, and an areal, steady-state groundwater model was constructed to calibrate the observed head values corresponding to the initial development phase of the aquifer. Initial and boundary conditions determined from the areal calibration were used to evaluate steady-state, hydraulic heads. Consequently, the initial position of the hydraulic head distribution was calibrated under steady-state conditions. The changes of initial hydraulic distribution, under discharge and recharge conditions, were calculated, and the present-day position of the interface was predicted. The present-day distribution of hydraulic head was estimated via a 20-year simulation. The results indicate that a considerable advance in seawater intrusion can be expected in the coastal aquifer if current rates of groundwater exploitation continue and an important part of the freshwater from the river is channelled from the reservoir for irrigation, industrial and domestic purposes.