Project Title: Stormwater Management And Drainage Master Plan Study For Daerah Barat Daya, Pulau Pinang

Funder: Department of Irrigation and Drainage (DID) Pulau Pinang


Duration: 11th November 2011 - 30th November 2013



Volume I: Executive Summary


Volume II: Introduction & Data Collection


Volume III: Stormwater Masterplan

Volume IV: Computer Modelling

Researchers :                           

                        Prof. Dr. Nor Azazi Zakaria <>
                        Prof. Dr. Aminuddin Ab. Ghani <>

                        Mohd Fazly Yusof <>

                        Muhamad Nurfasya Alias <>

                        Mohammad Safuan Mohammad Zulkufli <>

                        Leow Cheng Siang <>


Project Reports :

The project consists of five volumes as stated below:   


Volume I: Executive Summary

Volume II: Introduction & Data Collection

Volume III: Stormwater Masterplan

Volume IV: Computer Modelling


Executive Summary :

The planning of stormwater systems has moved significantly away from traditional concrete lined channels emanating from the depression era. Considerable use has been made of retarding basins to mitigate increased flood peaks due to urbanisation. Grassed floodways have largely replaced concrete channels to slow flow velocities and provide greater visual appeal and passive recreation areas. Additionally over recent years there has been an attempt to intercept a range of non-point source pollutants including general litter, sediment, and nutrients etc., utilising stormwater best management practices (BMPs) including gross pollutant traps, water quality control ponds and grass swales. There is also an increasing awareness of the ecological values of watercourses and the need to maintain and enhance these values. 

An effective water quality management strategy for an urban area involves managing construction and post-construction activities. Under both conditions, control of water quality can be undertaken at source, in addition to stormwater treatment prior to discharge to receiving water. The water quality management relating to construction activities involves the use of erosion and sediment control techniques during the construction phase. The general management philosophy involves the minimisation of erosion by diverting runoff from undisturbed catchments around work areas, rapidly revegetating disturbed areas, and trapping eroded sediment from disturbed sites.  

For the post-construction phase, the water quality enhancement can be achieved by controlling the pollution entering the drainage system. It is based on the premise that is generally easier and more cost-effective to control pollution at source rather than removing pollution from within the drainage system. Further, stormwater treatment measures alone may not able to reduce pollutants to pre-development levels. Two broad categories of source control exist, namely physical techniques and education. Treatment measures of stormwater runoff can be identified at established urban areas to remove urban pollutants in order to enhance the quality of discharges to receiving waters.

Ranges of stormwater BMPs are available which aim to improve the quality of post development stormwater runoff. There two major types BMPs, namely retention systems (e.g., wet basins, construction wetlands etc.) and infiltration systems (e.g. infiltration basins, trenches etc.) 

The Department of Irrigation and Drainage (DID) requires engineering consultancy services to prepare a Stormwater Management and Drainage MasterPlan Study for Daerah Barat Daya, Pulau Pinang.


Background :

The study area is located within the area of Barat Daya District (BDD). BDD is one among the five (5) districts in Penang and it has 12 territories. It is located in the southwest area of the Island (Figure 1.0). The total area is approximately 17345 hectares or 173.45 km2

Topographically, the study area is surrounded by hills and coastline. It has 19 river systems with total catchment area and length or 600 km2 and 102 km (Figure 2.0 and Appendix I). The focus areas are as Bayan Lepas, Bayan Baru, Balik Pulau and Teluk Bahang. The main economic activities in the study area are industrial, agriculture, fisheries, and tourism. Currently, there are significant on-going development in the study area, particularly in the area of the Balik Pulau and Bayan Baru and Bayan Lepas.  

There are eight (8) flood prone areas that were identified in the study area and they are Jalan Mahsuri, Taman Iping, Kampung areas in Bayan Lepas and Teluk Bahang and Kampung Simpang Tiga Air Putih (Refer to Appendix II). Flood occurs occasionally due to rapid development in the upstream catchment and due to the inadequacy of river and stormwater facilities inferring to river/drain malfunction such as clogging of rubbish, drainage lines discontinuity as well as silt coming from construction areas.


Objectives of Study :

The primary goal of the study is to minimise the impact of urbanisation on the stormwater environment and to strike a balance between social, economic and environmental concerns to achieve sustainable development. In order to achieve this, the study shall meet the specific objectives or urban stormwater management area as follows;  

1. To formulate the long term solution for the flooding, drainage and stormwater management problems in the existing built-up areas in order to reduce the adverse effects of flooding on people and property and to protect the existing and proposed development by implementation of an integrated stormwater management by providing an appropriate level of affordable flood protection to community expectations. 

2. To optimise the effectiveness of the existing stormwater infrastructure network within the study area in a way that meets the needs of the community and where possible, by providing and maintaining stormwater management infrastructure at an acceptable quality of services, taking into account environmental effects and public expectations. 

3. To control the excessive sediment in watercourses to acceptable levels by managing the catchment activities using at source control measures to prevent any acceleration of the rate of erosion from construction site, on land and in stream channels.  

4. Collect and convey stormwater from a catchment to its receiving waters with minimal impact by managing and improving the quality of stormwater runoff urbanized catchment and its pollution loads in order to reduce the adverse effects of non-point source contamination on the receiving water environment and by eliminate point source pollutions discharges to stormwater systems and receiving water in order to reduce the adverse effects of point-source contamination.

5. To protect and enhance the natural water-dependent ecosystems and enhance community access to and enjoyment of water courses environments and to protect and maintain the rivers environments of high environmental and aesthetic quality while promoting sustainable recreational opportunities, community health, aesthetic amenity and health environment.


Scope of Work :

Pursuant to the objectives as outlined above, the scope of work is drawn to describe the structured mechanism on how the project should be executed, as well as providing details on the issues and the associated areas to be addressed. The scope of work covers various components with activities ranging from data collection, identification of issues, planning and preparation of supporting documents. The scope of works shall include but not be confined to the following:  

1. Data Information Collection  

2. Topographical and Engineering Surveys and Geotechnical Investigations  

3. Site Investigation and Field Inspection  

4. Review of the Past Studies/Project  

5. Analysis Existing Conditions  

6. Identify Stormwater Issued and Problems  

7. Formulate Alternatives  

8. Compare Alternatives and Select Recommended Plan  

9. Development of Stormwater Management MasterPlan  

10. Cost Estimates and Benefits  

11. Prepare Plan Implementation Program  

12. Ownership of the Study