Salt intrusion in the Selangor : model study with Delft3D estuary in Malaysia

The Selangor River in Malaysia is the main source for drinking water for the densely populated area around Kuala Lumpur. Nowadays more than half of the river discharge is extracted, which causes the salt intrusion to advance further upstream in the downstream part of the river. For this study a numerical model is build with Delft3D to assess the impact of the water extraction on the salt intrusion. The point of departure was an existing large scale tidal flow model, which was refined and optimised to generate accurate boundary conditions for the coastal zone near the Selangor River. Subsequently a 3-dimensional model of the Selangor Estuary was build, which is capable of accurate predictions of the dynamic process of salt intrusion. The results of the study can be used to determine the effects for the valuable eco-system in the estuary and to improve the river basin management. The study was accommodated by Alkyon Hydraulic Consultancy & Research in the Netherlands. Two months of the research were carried out in Malaysia, hosted by the National Hydraulic Research Institute of Malaysia (NAHRIM).