4 
Ganl. Bull. Singapore 70 (Suppl. 1) 2018 
(Chan & Corlett, 1997; Ng, 1997) included detailed stream mapping (the original 
hand-plotted maps are kept on file), but longitudinal information on water quality 
and hydrological changes, and detailed spatial differentiation of plant and animal 
communities within the Nee Soon stream catchment have been very limited. This 
has resulted in uncertainties about the existence, magnitude, extent and rate of any 
changes. 
In order to obtain high quality information that would enable the National 
Parks Board to fulfil its statutory obligations of biodiversity conservation, funds were 
secured to carry out a multidisciplinary study on the hydrology and biodiversity of Nee 
Soon freshwater swamp forest. 
Scoping and project design 
An initial Phase 1 of the project was conducted from January 2011 to March 2012. 
The aims were: 
i) To establish what we know about Nee Soon freshwater swamp forest in terms of 
its ground and surface water environment and ecology; 
ii) To characterise the hydrology, geology, topography and flora of the freshwater 
swamp forest using measurements appropriate for the subsequent development 
of maps and models; 
iii) To develop a preliminary hydrological model (surface and groundwater flow); 
iv) To conceptualise and test an ecohydrological model characterising 
interdependence between groundwater flow and vegetation growth. 
Phase 2 of the project was conducted from February 2013 to August 2016. The aims 
were: 
i) To establish the status of Nee Soon freshwater swamp forest in terms of 
vegetation hydrology and aquatic biodiversity; 
ii) To identify periodic flux in hydrology and key components of the aquatic 
biodiversity; 
iii) To develop more refined models that can confirm current conditions (water 
balance, nutrient balance, acid flux, faunal distribution) and then test-trial 
various management scenarios; 
iv) To identify and assess the root causes of impacts, potential issues that may 
threaten the hydrological and ecological integrity of the swamp, and management 
elements to be addressed; 
v) To propose recommendations for possible mitigation of long-term negative 
impacts; 
vi) To establish a viable, long-term monitoring programme and develop sampling 
protocols to ensure continued protection and good management; 
