| Hong Kong enjoys the benefits of a water supply that boasts greater reliability as a result of improved infrastructure and increased monitoring of distribution networks. |
| IMPROVING THE SUPPLY NETWORK |
Annually, the number of reported cases of burst water mains
has reduced from 2 500 in 2000/01 to just 267 in 2012/13. Our
15-year phased programme of replacing and rehabilitating
3 000 km of water mains has resulted in greater supply
reliability. Hong Kong has over 8 000 km of water mains, many
of which are more than 30 years old. The current replacement
and rehabilitation programme has focused on 3 000 km. The
programme has reached its final stage and, as at 30 April 2013,
we had completed work on 2 091 km of water mains, reducing
water mains bursts, sudden drops in pressure and other incidents
that can disrupt water supplies and, in many cases, cause
traffic and transport disruptions. The current replacement and
rehabilitation programme will be completed by 2015 and plans
are in hand to launch a second phases of replacement and
rehabilitation involving some of the remaining 5 000 km of mains.
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| Pipe rehabilitation work of large diameter pipe photo |
| Pipe replacement work photo |
| Pipe rehabilitation work – spray applied lining photo |
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| MAXIMISING INFRASTRUCTURE | |
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Improvements will be made to catchwaters to further ensure the safe and efficient collection of surface water. The first of these projects will involve improvements to 26 kilometres of catchwaters in the Shing Mun, Beacon Hill, Golden Hill and Tai Lam Chung catchwater systems.
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| IMPROVING SUPPLIES | |
We are constantly expanding and improving the infrastructure needed to ensure Hong Kong has adequate supplies of both fresh water and seawater. New initiatives include improvements to salt water systems and pumping stations at Chai Wan and Siu San Wan. An additional 4.6 km of salt water mains are being laid to meet the growing demand in the area. A salt water supply system to be used for toilet flushing in Tung Chung has proceeded to detailed design stage. Fresh water supplies to areas of Central are being improved through the expansion of the existing Albany Reservoir in Mid-Levels. New housing development areas at Lok Ma Chau and Kwu Tung North will be catered for by construction of a new fresh water reservoir at Kwu Tung North. The installation of a cross-harbour fresh water submarine pipeline, 1 200 mm in diameter and 2.1 kilometres in length, under the western part of Victoria Harbour between West Kowloon and Sai Ying Pun, has been completed. The new cross-harbour main not only helps to cater for the increased water demand of Hong Kong Island, but also plays an important role in enhancing the reliability of the fresh water supply to Hong Kong Island. |
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| Capital Investment Photo | Statistics on Mains Bursts Repaired Photo |
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| UPGRADING TREATMENT CAPACITIES |
Planning and construction work is underway at the Sha Tin Water Treatment Works and the Tai Po Water Treatment Works respectively – two major facilities used to treat raw water before it is distributed across Hong Kong. The Sha Tin plant is to be reprovisioned while the Tai Po plant is undergoing a significant expansion. Both will ensure that we have adequate capacity to treat raw water to current drinking water standards and to higher standards should they be introduced in the future. Careful phasing of work means that at all stages of construction, the treatment capacities of the two facilities will meet the required aggregate demand for water. The capacity of the Tai Po Water Treatment Works will be increased from 250 000 cubic metres per day to 800 000 cubic metres per day in two parts at a cost of $5.6 billion. Part 1, taking the treatment capacity up to 400 000 cubic metres per day, was completed in 2011. Part 2 of the Tai Po Water Treatment Works expansion which began in February 2013 will increase the capacity of the works to 800 000 cubic metres per day. The plant is due to be commissioned in 2017. The detailed design of the in-situ reprovisioning of the south works of the Sha Tin plant is underway and is scheduled for commissioning by the 2020s. |
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Other major improvement works undertaken include the retrofitting of the North Works of the Sha Tin water Treatment
Works. Inclined tubes have been installed to improve the plants' treatment capacities. A clarifier at the Sheung Shui Water Treatment Works has also been retrofitted with inclined tubes to produce a similarly positive outcome.
Fresh water augmentation has been introduced at the salt water supply systems in Tsuen Wan and Kwai Tsing to enhance the reliability of flushing water supplies. We have also provisioned the decking over the Ha Lo Wai salt water reservoir for safety reasons. |
| Inclined tubes at clarifier of Sheung Shui Water Treatment Works Photo |
| OPERATIONAL EFFICIENCIES |
We have upgraded our SCADA system which is used to
centrally oversee facilities such as pumping stations and service
reservoirs from four regional control centres to improve the
operational efficiency of territory-wide water supply networks.
To further enhance reliability of the system, alternative control
centres are being established at each of our four operational
regions in Hong Kong. The alternative control centre for the New
Territories West region is already operating whilst the remaining
three new centres are under construction.
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Control systems at water treatment works at Yau Kam Tau, Ma On Shan, Pak Kong, Sheung Shui and Tsuen Wan have been upgraded and similar upgrade programmes are underway at Ngau Tam Mei and Tuen Mun water treatment works and some
key pumping stations to ensure efficient, reliable and effective operations. Across the board, IT infrastructure and application systems have been introduced to enhance the quality of services.
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In line with on-condition monitoring studies, we are continuing to improve the performance of plant equipment. A web-based management system to monitor pumping efficiency has been successfully tested for rolling out at 10 pumping stations. To facilitate maintenance without causing supply interruption, we are adding compartment walls to sea water service reservoirs which currently operate with just single compartments.
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When there is an emergency situation such as a mains burst, our first recourse is to maintain an uninterrupted supply by shifting the water supply zone wherever possible. If this is not possible, we will provide a temporary fresh water supply to customers to meet their basic need should they face a temporary suspension of supplies due to an emergency which is expected to last for more than three
hours. Emergency temporary fresh water supplies are provided through standpipes, water wagons or water tanks. To enhance the service, we have doubled our fleet of water wagons to 10.
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| OPTIMISING ASSETS |
We aim to manage the life cycle of all water services infrastructure so that we can achieve a desired level of service cost-effectively and within an acceptable risk framework. Over the past year we have completed four surface assets management plans. These plans identify the performance and physical condition of some 900 waterworks installations. Once improvement works have been identified, they are prioritized for implementation over the coming years. Under a Reliability-Centred Maintenance programme we have completed the review at a water treatment plant and two key pumping stations. As a result, we have the basis for a comprehensive model of maintenance strategies for mechanical and electrical assets. The programme will be rolled out at another water treatment works and two more pumping stations in 2013 for continuous improvement of services. Slope maintenance remains an important programme. The maintenance of almost 6 500 slopes has been assigned to the Department by the Lands Department. In turn, we routinely inspect these slopes and, where necessary introduce monitoring, maintenance and upgrading measures to reduce any deterioration in stability. |
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Water quality monitoring during field exercise for Daya Bay Contingency Plan Photo |
| CRISIS MANAGEMENT |
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We are constantly identifying and managing risks across the entire supply system. Crisis management and the ability to maintain an uninterrupted water supply should any extraordinary event occur are ongoing challenges. A crisis management plan and various contingency plans are in place to maintain a state of preparedness for the rapid mobilisation of resources and the co-ordination of emergency actions. In April 2012, the Department participated in an inter-departmental exercise involving the Government's Daya Bay Contingency Plan. The exercise simulated an off-site incident at the Guangdong Nuclear Power Station. Both desktop and field exercises were successfully conducted to test the effectiveness of our Daya Bay Contingency Plan and to monitor the level of coordination achieved with other departments in handling an emergency at the power plant. |