Paper was presented in the Water 2000 Forum on May 2 - 5, 2000.
RIVER BASIN MANAGEMENT - THE SUNGAI SELANGOR EXPERIENCE
By Tan Sri Wan Azmi Wan Hamzah
Chairman of Syarikat Pengeluar Air Sungai Selangor Sdn Bhd (SPLASH)
Definitions
Water and other natural resources within a river basin play significant roles in satisfying our human needs. A river basin contributes forage for livestock and wildlife species, furnishes a diversity of natural products and yields water for human consumption as well as agricultural and industrial developments.
By definition, a river basin is a topographically delineated area that is drained by a system of rivers, including their tributaries, into the sea.
River basin management is the process of organising and guiding land and other resource use within a river basin so as to achieve the desired objectives without adversely affecting soil and water resources. Embedded in the concept of river basin management is the recognition of the inter-relationships between land use, development needs, soil and water, and the linkages between upstream and downstream areas. The practice of river basin management encompasses changes in land use, soil, water and vegetative cover, and other non-structural and structural actions that are implemented within the river basin to achieve river basin management objectives.
Importance of the Sungai Selangor River Basin
"Water, water everywhere, and not a drop to drink". This mantra was often heard during the water crisis of 1998. It is important that to maintain our lead towards a developed nation, our water supplies must be reliable. By 2005, Sungai Selangor will supply two thirds of the potable water needs for population and industries within Selangor and Kuala Lumpur. Hence, it is a very important raw water source, and an integrated approach is needed to manage the river basin for future sustainable development.
In general, the uppermost reaches of the main river basins in Selangor fall within Class II (water bodies of good quality), with the exception of Sungai Selangor, where most of the upper reaches are of pristine Class I quality. On the other extreme, the Sg. Klang, Sg. Buloh, Sg. Sepang and Sg. Tengi where significant sections of the river are of Class III (may be used for water supply with extensive / advanced treatment) to Class IV quality. It is also evident that marked deterioration occurs along the mid-stream and downstream reaches where most of the rivers become Class III or IV quality. Pollution sources located within the mid-stream and downstream parts of the river basins contribute to the deterioration in water quality. The main pollution sources in the State include sewage, industries, agricultural development, animal husbandry and land development.
An integrated or holistic approach to river basin management is needed to ensure harmony between man and land. This will create inter-sectorial linkages between the physical, biological, economic and political components to ensure the future sustainable development of the Sungai Selangor river basin.
Protection of raw water source
The proposed Sungai Selangor Regulating Dam is part of the overall Sungai Selangor water supply scheme. The Regulating Dam functions as a regulating reservoir where regulation of the river flow in Sungai Selangor will enable sufficient amounts of raw water to be reliably abstracted at the Rasa and Batang Berjuntai intakes.
The catchment area upstream of the Regulating Dam, some 197 square kilometres will be designated by the State Government to be a water catchment reserve. Hence, protection from development is assured.
However, downstream of the Regulating Dam, the catchment area covers over 2,500 square kilometres, making it unfeasible to designate it as a catchment reserve.
Raw water at the abstraction points must continue to be of a quality suitable for the purposes of drinking after treatment. Therefore it is important to ensure that the raw water quality is not adversely affected as a result of development within the basin.
The issue of river basin management has become a major concern and has initiated stern actions from the authorities.
Joint Responsibility
The responsibility for river basin management requires complex interfacing and co-ordination effort that is typically disbursed across a number of Government agencies, including the water authorities, land planners, forestry agencies, etc. Hence, it will require multi-disciplinary collaboration, sustained efforts as well as commitment by Government agencies and local communities.
Currently a proliferation of Government agencies is involved in the planning, development, regulation and control of activities in river basins. Some of the principal agencies that are responsible include :
- Forestry Department
- Department of Wildlife
- Department of Environment
- Department of Agriculture
- Department of Town and Country Planning
- Department of Fisheries; and
- Drainage and Irrigation Department
These have led to limited effectiveness in the provision of the services with consequent deterioration of the river environment. The problem is compounded by the following weaknesses :
- Where a river flows through several districts, issues pertaining to river management are handled by different land offices
- Where a river traverses through two states, problems in water use allocation arise, and competing usage with limited co-ordination with respect to planning between the two states
- Inadequate monitoring and enforcement due to under-funding and under-resourcing of the agencies
- Current water related laws are not sufficiently provided to cover present day circumstances
The present ad hoc and sectorial approach to river basin management has resulted in uncoordinated planning and approval of development works in the river basins. In some cases, this has led to conflicts in water allocation among the various users. An integrated approach to planning, management and enforcement is essential. The formation of LUAS is a major milestone towards river basin management in Selangor and Malaysia.
Strategies for River Basin Management
The strategies for a comprehensive river basin management programme includes :
- Water quality monitoring for detection of pollution sources and enforcement purposes
- Zoning of industries with the possibility of having to relocate industries that are known to pollute waterways to properly sited industrial estates downstream of the intakes
- Relocation of squatter settlements along river banks
- Establishing a buffer zone along riverbank reserves where no development is allowed
- River clean-up and beautification programmes
The execution of an effective river basin management programme requires committed and concerted effort among the private sector, state authorities and agencies to curb river water quality pollution and degradation
Managing Future Developments
To ensure future sustainability of Sungai Selangor as a source of potable water, judicious land use planning and control within the river basin is needed. All these should be co-ordinated by a central agency to ensure that any future land use or development will not detrimentally impact the water quality.
Measures that should be implemented include:
- Zoning for land use
- Control of industrial sites, including the types of light, dry and non-polluting industries that are allowed within the river basin
- Control of the use, storage, transport and disposal of toxic substances
Many of these measures can only be implemented by the Government and relevant authorities. However, SPLASH, as a corporate body can complement Government's role by providing information on the changing quality of the river water.
River Quality & Monitoring System
As part of its operational requirements, SPLASH will introduce an early warning system upstream of the Rasa and Batang Berjuntai intakes. The objectives of this system are to :
- Provide early detection of high pollution levels in the raw water so that the water treatment plants are protected and to ensure that the production of treated water is not disrupted due to any failure in the equipment
- Constantly monitor the trends in raw water quality in respect of concentration levels and pollutant types
- Provide information to the enforcement agencies in the event that increased pollution loads are detected
The unmanned river monitoring system that will be put in place will consist of automated sampling systems with sample analyses systems and a SCADA system. These systems will be housed in a station, which is just a purpose built building with power supplies and communications equipment.
The sampling system will regularly collect river water samples at preset intervals by means of a submersible pump. The raw water sample will then be piped to the station, where it is drawn into the sampler. Parameters will be measured through various probes, and the results recorded into a database. The data will then be transmitted using the communications link to the Command Centre that is located at the water treatment works at Rasa and Bukit Badong. The data will be used by the operations staff who will assess the condition of the river water, and decide on the appropriate actions that will be taken.
The parameters that will be measured is based on the current raw water quality, which is related to present activities, and the expected future activities within the river basin. This will include :
- pH
- Chemical Oxygen Demand (COD)
- Turbidity
- Ammonia
- Oil and grease
- Colour
These parameters were chosen because :
- They are all important parameters that affect the efficiency and effectiveness of the proposed treatment process at the water treatment works
- COD is an indicator for pollution
- Turbidity provides an indication of the suspended and dissolved solids content in the raw water
- Ammonia indicates the level of pollution caused by sewage discharge and fertiliser application
- Oil and grease indicates industrial and domestic discharges
The river monitoring stations will be located between 2 to 4 km upstream of the Rasa and Batang Berjuntai intakes, which allows a lead time of about 1 to 2 hours.
Apart from advance warning of pollution threats to the operators of the water treatment works, the data collected will be stored in a database so that trends of pollution levels can be monitored and analysed. This information can be provided to the relevant Government agencies for enforcement purposes.
Mapping
SPLASH will assist the Government map out and locate the developments that are within the Sungai Selangor river basin. The types of developments and industries as well as any illegal squatters or backyard industries that are located along water courses will be identified.
Water samples will be taken along tributaries to see what pollutants are present, and in what concentrations. All this information will be used as a baseline to benchmark against future pollution loads. From the information gained at each sampling point, the major sources of pollution can be quickly detected and the information passed on to the enforcement agency
River basin management must be acknowledged to be an essential ingredient for the successful achievement of a better water environment for Selangor and indeed for Malaysia. SPLASH will complement Government and LUAS' efforts towards an integrated approach to river basin management. We have to preserve the environment of our rivers - for our present and to secure our future.
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