Environmental Protection Department - Environmental Performance Report 2005

Environmental Performance Report 2005
Environmental Protection Department

| 5.1 Our Contribution to Strategic Decision-Making | 5.2 Planning for a Better Environment | 5.3 Effective Enforcement and Emergency Response | 5.4 Building Partnerships and Customer Service | 5.5 Environmental Awareness and Education | 5.6 Professional Development and Research |

5 Our Contribution to the Environment
5.2 Planning for a Better Environment

5.2a	Prevention and Mitigation through Environmental Impact Assessment
5.2b	Better Air Quality
5.2c	Quieter Environment
5.2d	Better Water Quality
5.2e	Environmentally Sound Waste Management and Facilities

5.2d

Better Water Quality

| Our Responsibilities | Water Quality in 2004 | Achievements in 2004 |

Our Responsibilities

We aim to ensure that the quality of our marine and freshwater is such that the various conservation goals for them can be met, and that plans are formulated and implemented to ensure Hong Kong's sewage systems can operate safely and effectively both now and with future urban development.

Water Quality in 2004

Water quality is monitored in rivers, beaches and marine waters to measure compliance with Water Quality Objectives (WQOs) and protect the health of the public and the environment. Over the past 15 years, there has been much improvement in overall water quality, although some problem areas still need addressing, such as western Victoria Harbour.

Photo of Overall water quality has been much improved over the past 15 years.

In 2004:

•	87% of marine water samples met WQOs, similar to that in 2003.
•	82% of river and stream samples met WQOs, similar to that in 2003.
•	34 of 41 gazetted beaches (83%) met WQOs for bathing beaches, the same as that in 2003. A breakdown of results in 2004 can be seen at Table 1. The beach water guidelines are health-based.

Table 1 - Beach Water Quality in 2004
Beach rank	Number of beaches
Good	25 (61%)
Fair	9 (22%)
Poor	5 (12%)
Very Poor	2 (5%)

Some 6.2 million Hong Kong people currently are served by public sewage treatment systems, as seen in Figure 1.

Figure 1 – Areas served by public sewage treatment systems.

Harbour Area Treatment Scheme (HATS)

Stage 1 of HATS began operating in 2001 and significantly improved the water quality in eastern and central Victoria Harbour. The next stage has been widely debated. An International Review Panel (IRP) of experts recommended several options in 2000 (see Figure 2).

Figure 2 - Schematic map of HATS options.

Detailed studies of these options were completed in 2004 and the public was consulted on the government's proposal as follows, with option A as the prefered option:

Divide the second stage into two phases.
In Stage 2A, the remaining 450 000 tonnes of untreated sewage from Hong Kong Island would be given chemically-enhanced treatment (CEPT) plus disinfection at the existing treatment plant on Stonecutters Island. Disinfection would also be applied to the Stage 1 sewage. In Stage 2B, a biological treatment plant would be built, with the commencement date dependent on trends in water quality in the harbour and future sewage loads. Cost is a consideration in this approach because it staggers the $19.5 billion outlay required for all of Stage 2 (see Figure 3 - Breakdown of Costs). In any case, sewage charges will have to increase.

Figure 3 – Breakdown of Costs.
	Capital Cost (HK$billion)	Recurrent Cost (HK$billion per year)
Stage 2A	8.4	0.44
Stage 2B	11.1	0.72
Total	19.5	1.16

2.		Disinfect sewage in Stage 2A. The beaches at Tsuen Wan are strongly influenced by effluent from Stage 1 of HATS. Bacteria in the effluent will need to be adequately removed if these beaches are to be reopened. The government proposes to do this through chlorination after the CEPT process, but the treated effluent would need de-chlorination before being discharged. An EIA will assess the effects of this technique.

3.		Build the biological treatment plant underground, next to Stonecutters Island. The IRP recommended biological aerated filter treatment because of its compactness. Studies found this technology could apply in Hong Kong.

4.		Keep sewage treatment at one site. Some people in the community have suggested using two or more sites, but this was considered impracticable and costly.

5.		Use conventional contractual arrangements. A design-build-operate contract could be suitable for treatment plants, as it would expedite the delivery of the project. But since the Drainage Services Department already operates the Stonecutters Island plant, any application of the DBO approach to Stage 2A would need more careful consideration of the interfaces involved. The approach may be considered for Stage 2B.

Consulting the public
A five-month public consultation on HATS ended on 20 November 2004. District Councils, green groups, academics, professional bodies, business and industry groups, and legislators were consulted, and an extensive community education programme was launched to encourage the public to express their views.

Most comments focused on the phasing proposal. Some concerns were expressed about chlorination, others about the timing of Stage 2B. The government will address chlorination in an EIA of the project, and will build Stage 2B based on water quality trends after 2A is commissioned. The government is now reviewing comments from the public and will report to the Legislative Council in the first half of 2005.

Regional Issues

The EPD is working with the Shenzhen Environmental Protection Bureau on a programme to review the Deep Bay Water Pollution Control Joint Implementation Programme, aiming to complete the review in 2006.

The EPD is liaising with the Guangdong Environmental Protection Bureau to develop a water quality model for the Pearl River estuary. Data has been collected and fieldwork completed, and the modelling contractor is now constructing the model. The model should be ready by early 2006.

Toxic Pollution

A programme to sample and test for toxic substances in the marine environment was begun mid-2004 and will be conducted once a year. At the same time, a biological indicator monitoring programme was begun to assess the effects of pollution on the ecological health of the marine environment.

China ratified the Stockholm Convention on the reduction of persistent organic pollutants in 2004 and this was extended to Hong Kong. Signatories are required to draft an implementation plan. Hong Kong is now drafting its plan, which will be included in China's National Implementation Plan for submission to the Stockholm Convention Secretariat by November 2006.

Photo of Trawling for marine biota to obtain tissue for toxic substances analysis.

Photo of The Stockholm Convention is a global commitment to rid the world of persistent organic pollutants.

Other Water Issues

Funding approval is being sought for a $14.5 million pilot effluent re-use scheme at Shek Wu Hui. A high-level treatment unit will be added to the existing secondary sewage treatment plant to produce high quality reclaimed water for flushing, irrigation and water features in the Sheung Shui area. The project is expected to begin operating in 2006 for a two-year trial.

An in-house study on storm water pollution was completed. The study focused on Mongkok and estimated that BOD loading equivalent to 12% of the sewage generated from the area ended up in storm water drains. The pollution came from sewage from defective sewers, expedient connections, and non-point source pollution such as street washing. The findings indicate the need for a comprehensive approach to control this problem.

Photo of Re-using treated effluent wherever possible forms an essential component of a holistic water management strategy.

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