Advisory Council on the Environment

The Acting Chairman welcomed the presentation team led by Mr. K K Lee to the meeting. Mr. K K Lee informed Members that the purpose of undertaking the preliminary management measures was solely to facilitate the design of enhancement measures for the fishponds at Lok Ma Chau. He emphasized that the information paper sent to Members was not required as part of the EIA report but to provide detailed information on the preliminary management measures so as to enable Members to better understand the enhancement measures. The enhancement ratio of two was chosen to fulfill the compensation requirement under the Technical Memorandum of the EIA Ordinance (TM). In fact, KCRC was confident that a ratio of much higher than two could be achieved with the enhancement measures proposed. Mr. Paul Leader and Dr. Michael Leven then briefed Members on the preliminary management measures carried out in fishponds at Lok Ma Chau.

Bird number observed

2. A Member asked why the enhancement of the fishponds at Lok Ma Chau was measured by the number of birds observed. In response, Dr. Leven explained that there were two main reasons. The first one was because water birds were of primary ecological importance in the wetland system at Lok Ma Chau and the second reason was that bird number was a quantifiable and comparable unit for measurement. There were many examples in which the carrying capacity of a wetland habitat was measured by the number of birds observed.

3. In reply to a hypothetical question raised by that Member, Dr. Leven said that if all the fishponds in Deep Bay area other than those in Mai Po were filled, he would expect a temporary increase in the number of birds observed in Mai Po but the total number would decrease significantly in the long run. That Member then said that if the increase in the number of birds observed indicated enhancement of the carrying capacity of a fishpond, then in the hypothetical case the fishponds in Mai Po could be considered as "enhanced". Dr. Leven disagreed with that Member's comments and said that in the present EIA, the objective was to increase the carrying capacity of the fishponds through enhancement measures in a sustainable manner to ensure that no less number of birds would continue to use the area in question.

Management measures on fishponds

4. A Member said that whilst she recognized the need for the railway project, she shared Members' concern over the possibly irreversible adverse impacts on the environment. She asked whether there was a contingency plan in case the proposed mitigation failed to achieve the objective. In reply, Dr. Leven said that the enhancement measures involved simple work of pond re-profiling, fish stocking in summer and progressive drain-down of ponds in winter. They had full confidence in the effectiveness of the enhancement measures which were neither new nor unique and could be carried out by any professionals that possessed the expertise. A further fallback action was to stock fish directly into the ponds in winter to provide adequate food for the birds. He assured Members that the project proponent was legally obliged under the Environmental Permit issued under the EIA Ordinance to implement the compensation measures effectively.

5. A Member pointed out that the stocking of fish in the manner described would not be sustainable as the fish would be consumed in a few days after the ponds were drained. In response, Dr. Leven said that the ponds would be drained down sequentially to sustain throughout the winter season.

6. A Member enquired about the existing land-use of the proposed mitigation areas and whether they provided desirable habitats for birds. He said that Tilapia was a large fish and doubted if it was suitable for feeding the target bird species. Having regard to some Members' concern over the possibility of inadequate food supply during winter, he suggested that the project proponent should use aqua farming to produce fish fry for stocking purpose.

7. In response, Dr. Leven said that the mitigation areas were currently used as commercial fishponds which would lose their ecological value as a habitat for birds if left unmanaged, as they would become too acidic for aquatic organisms. The size of the Tilapia they obtained from fish farmers was only 6cm to 8cm long and would be suitable for the target species. As regards the supply of fish fry, the project proponent would work closely with fish farmers to ensure adequate supply.

8. Mr. Paul Tang pointed out that the ecological value of commercial fishponds would depreciate in the natural course of development. Under the proposed enhancement programme, the commercial fishponds would be actively managed by the project proponent to preserve their value. In this context, one could say that the project would result in ecological gains instead of ecological loss for the fishponds concerned. A Member said that fish farming was quickly phasing out in Hong Kong. In his views, commercial fishponds would provide little value, if any, to bird species in the long run if left unattended. Regarding the management measures proposed for the fishponds, he cautioned that too many birds might be attracted to the area because of the management measures and that a proper balance should be maintained.

9. A Member cautioned that frequent draining down of the fishponds would expose the sulphur-contained soil to the air and increase the acidity of the water. On the other hand, if pigeon faeces and peanut residue were added to neutralize the acidity, the ponds would become deoxygenated and could no longer support wildlife at the end of the day. In response, Dr. Leven pointed out that the pH level of the water would be normally set right when the ponds were drained and refilled. Pigeon faeces and peanut residue would only be used when necessary.

Predictions on bird number

10. A Member asked why a factor of 98.5 was adopted in Table 3 of the information paper to predict the number of birds in the managed ponds at Lok Ma Chau. In response, Dr. Leven explained that in fact a factor of 135, which was the number of days in the period from 1 November 2000 to 15 March 2001, was adopted to predict the number of birds in Mai Po ponds and gei wai. A smaller factor of 98.5 was adopted for the Lok Ma Chau managed ponds because those ponds were abnormally stocked four times during that period. It would be more reasonable and conservative to use a reduced factor for the Lok Ma Chau managed ponds.

11. In reply to a Member's enquiry, Dr. Leven said that the managed ponds in Lok Ma Chau and the controlled ponds in Pak Hok Chau referred to in Table 2 of the information paper were broadly comparable in number and size. That Member said that the predicted number of birds was impressive but it was only based on a few months' trial. He asked whether there would be any concrete management plan and contingency plan for the fishponds. In response, Dr. Leven explained that the preliminary management measures were carried out to form the basis of the Habitat Creation and Management Plan (HCMP) which would contain the action levels that trigger remedial measures if necessary and the targets of the actions. The HCMP was a document usually required as a permit condition and which would be scrutinized and approved by the authority.

12. A Member asked whether there was any pre-managed data on fishponds in Table 2. Dr. Leven replied that the data was contained in the EIA Report but had to be disentangled to get the pre-managed set of data.

13. A Member said that from a scientific point of view and in view of the lack of statistics to support the conclusion, he had serious doubts in the predicted number of birds in the managed ponds (Table 3) which was purely based on the observed bird number (Table 2). In response, Dr. Leven explained that the preliminary management measures were intended to gather experience to draw up the HCMP. The figures were not presented as a rigorous scientific study as such.

14. A Member queried the accuracy of the predictions which were solely based on Table 2. He said that the data was only collected in one season and there could be many variables other than the enhancement measures that affected the results. An example was the different degrees of disturbance in different ponds. Dr. Leven agreed that factors like disturbance would affect the number of birds using the area but the objective of the preliminary management measures was to ensure that at least the same number of birds would continue to use the area and that was demonstrated in the preliminary measures.

15. In reply to that Member's question on which set of data would be adopted as the baseline for predictions, Dr. Leven said that both the baseline data for Lok Ma Chau area in winter 2000/2001 and the continuous data for existing commercial fishponds were available to be used as the baseline. The latter set of data was preferred because it reflected recent changes in the number of birds.

16. A Member was not convinced that a reliable set of baseline data could be established and therefore he had no confidence in the predicted number of birds in the Lok Ma Chau managed ponds. He said that it would be easy to get a number that met the targets if the counting was done right after the stocking of fish. However, there would be no guarantee that the birds would stay throughout the season. Dr. Leven stressed that Members would have to put in some degree of confidence in the integrity of the project proponent and the contractor. The Acting Chairman brought Members' attention to s.5.5.1 of Annex 16 of the TM which stated that the Ecological Monitoring and Audit (EM&A) Programme was "to verify the accuracy of the predictions of the ecological assessment study; … and to recommend action plans in response to unpredicted impacts, and/ore failed mitigation". He further said that the issue on how to ensure that the proponent could deliver the proposed mitigation results could be addressed when the EM&A programme was drawn up.

17. Mr. K K Lee assured Members that the EM&A Manual would be the next item on the action list and they had committed themselves to the proposed mitigation work. They welcomed the participation of green groups in that respect.

Other wildlife

18. A Member asked whether the impacts on species other than water birds had been taken into account in the mitigation proposal. In reply, Dr. Leven informed Members that Table 4.2 to 4.7 of the EIA Report listed out all the species of conservation importance in the area. Since the Lok Ma Chau area comprised mainly fishponds which did not provide a good environment for a lot of other wildlife, mitigation for species other than water birds was less rigorous. He then quoted the example of vegetation around the fishponds which was quite common and heavily modified by local fish farming activities. He informed Members that the draft HCMP proposed a planting which aimed at bringing native species back into the system and made it more valuable than the existing vegetation.

19. In reply to that Member's follow up question, Dr. Leven said that a full vegetation survey was conducted and included in the EIA Report.

20. A Member pointed out that the mitigation programme appeared to have neglected species other than birds, for example, the Eurasian Otter. In response, Dr. Leven explained that there was a list of species of conservation importance in the EIA Report. Mammals were definitely not neglected. During the 18-month survey, the consultant had installed infra-red cameras to record mammal activities but there were only two sightings of Eurasian Otter. The conclusion was that the area was probably not a primary habitat for that particular species.

The concept of "disturbance impacts"

21. A Member considered that doubling the carrying capacity of the fishponds would not be sufficient to compensate for the actual loss because in the EIA report certain areas were not counted as habitat loss. At the same time, the Black-faced Spoonbill, a globally endangered species, should not be treated in the same way as other water birds. It deserved more cautious mitigation measures. In response, Dr. Leven clarified that under the "disturbance impact" concept, some areas in close proximity to the border fence where there was great disturbance were not counted as habitat loss. But on the other hand, the concept would require the project proponent to implement more measures to mitigate "disturbance impacts" caused by the project. Regarding the Back-faced Spoonbill, the buffer area for conserving this species of birds was drawn up based on professional judgment and 30 years of field experience.

22. A Member enquired about the change of the enhancement factor if the buffer zone increased from 100m to 200m. In response, Dr. Lynn Smith said that she could not give an exact figure right away on this hypothetical situation. However, if the disturbance distance from the station were increased from 100m to 200m, then the area currently subject to disturbance could correspondingly increase, encompassing more of the Lok Ma Chau Station footprint. The impacted area thus comprises a smaller part of the station footprint and a slightly extended disturbance band around the station footprint. The compensation requirement for the impacted area would still be achievable within the compensation area available.

23. A Member said that if the concept of "disturbance impact" was applied, the wetland compensation scheme currently undertaken for mitigation of other railway or highway projects might become unacceptable because more mitigation measures would be required. In response, Dr. Leven said that that the present project was the first one in Hong Kong that had taken on board "disturbance impacts". He agreed that the new approach would cut both ways. On one hand, the proponent would be required to mitigate a larger area. On the other hand, the total ecological value of the affected areas might be reduced according to that concept.

Measurement of carrying capacity

24. A Member said that a good baseline and an effective system were starting points of successful mitigation measures. The World Wide Fund For Nature Hong Kong had been managing Mai Po Nature Reserve since 1984 but there were no targets set to manipulate the carrying capacity of the habitats. The only quantitative scientific measure of the carrying capacity of a habitat was done for the mud flats in the Shenzhen River Regulation Study, in which the energetic production of food that could be used to support birds as well as the energetic requirements of individual species were adopted as the basis. She wondered why the project proponent proposed to adopt the approach of measuring the number of birds observed for the present project. In response, Dr. Leven clarified that they had adopted a conservation-based approach in which the species of conservation importance was the major concern, therefore the success of mitigation should be measured by the number of those species in the area.

25. A Member asked if the enhancement of habitat was possible, how it was measured in other countries. In reply, Dr. Leven said that an international unit of measuring the success of enhancement was the numbers of target species. Mr. Elvis Au added that according to his experience in studying ecological assessments conducted in other countries, EIA reports produced in Hong Kong usually included very detailed ecological assessment. One could say that Hong Kong was in the leading front as far as ecological assessment in EIA reports was concerned.

Judgment of the EIA Appeal Board

26. A Member quoted from the Judgment of the EIA Appeal Board regarding the previous Spur Line EIA report that "the more ecologically important the site, the more caution is necessary. The necessary test is, on balance, whether a particular measure has a reasonably high chance of success." Therefore he believed that the crux of the matter would be whether Members considered that the proposed mitigation measures had a reasonably high chance of success.

Other concerns

27. A Member reiterated that apart from compensation measures at Lok Ma Chau, the project proponent should take note of Members' concerns in other areas such as the inadequacy of the hydrology modeling and the monitoring parameters for groundwater table in Long Valley and surface/sub-surface settlement. Mr. K K Lee said that he noted that Member's comments and would work on them. 28. The Acting Chairman also urged the project proponent to pay attention to the monitoring of the performance of contractors. Mr. K K Lee said that they would set up an environmental committee to be chaired by the Senior Director, Capital Projects and represented by members of the public including green groups as well as the contractors. The committee would closely monitor the environmental work of the project. A Member commended the proponent's initiative and said that it would set a good model for future projects.

29. The Acting Chairman thanked the proponent for the presentation and the information provided.

Internal discussion

30. A Member considered that the principle of "no-net-loss" in wetland as stated in the Town Planning Board (TPB) Guidelines should be observed. Mr. C C Lay made reference to paragraph 6.1 of the Guidelines and advised that if the Spur Line was "an essential infrastructural project with overriding public interest, it should be admissible under the TPB guidelines if the proponent could demonstrate that the project would not result in a net loss in wetland functions. He said that the point would hinge upon whether Members considered the Spur Line an essential infrastructural project with overriding public interest. He further said that there were a lot of overseas cases of compensation by enhancement with compensation ratios comparable to that proposed in the EIA report. In the present case, the proponent proposed to compensate the loss in functions by enhancing the carrying capacity of the fishponds through re-profiling and other management measures that had been proved successful in Mai Po gei wai. Mr. Elvis Au referred to s.5.4.1(c) of Annex 16 of the TM and supplemented that under the TM, enhancement could be considered as a means of compensation.

31. A Member said that the crux of the problem was whether the proposed enhancement could make up for the loss of wetland functions in the long run and preserve the species of conservation importance. He considered that from an academic angle, the data in Table 2 & 3 of the information paper was over-interpreted and he had doubts on the effectiveness of the enhancement measures. Another Member said that the number of birds observed was an inaccurate and misleading unit of measurement for "carrying capacity" or "ecological functions" however narrowly that was defined. She suggested that a relatively more effective and accurate measurement would be the productivity of the habitat and the energetic requirements of the target species.

32. Mr. Patrick Lai informed Members that fishpond was a habitat that had been intensively studied in Hong Kong. According to Dr. Lew Young, the ecological value of commercial fishponds was most obvious during the drain-downs for serving as foraging grounds for water birds. In that regard, the proposed enhancement measures were simple and could be carried out easily. A Member said that the fishpond system might be well studied but not the behavior of Black-faced Spoonbill. He maintained the point that the number of birds observed could be manipulated easily.

33. A Member said that she was impressed by the results of the trails but was concerned about the fall-back arrangement if the proposed mitigation measures could not deliver the specified results. Sharing that Member's views, another Member said that ideally the effectiveness of the proposed enhancement measures would be better verified if more studies could be done but practically there was time constraint in carrying out more trials. The whole issue therefore boiled down to whether Members believed that the proposed management measures for the fishponds at Lok Ma Chau would have a high chance of success. If so, there would be no problem. If not, the Subcommittee could only look for a sound monitoring programme and contingency measure that could ensure further compensation in case the proposed measures failed. A third Member agreed with the second Member and suggested requiring the proponent to implement further measures (e.g. to acquire additional land) to compensate for the loss of fishponds if the management measures failed to achieve the mitigation targets through the proposed enhancement measures. Two other Members expressed consent to the second and third Members' suggestions and agreed that it was a more practical way to deal with the issue.

34. In response to Members' enquiry, Mr. Au confirmed that under the EIA Ordinance, the Director of Environmental Protection (DEP) could require the project proponent to compensate for any shortfall of mitigation measures. As regards monitoring, DEP could require the proponent to employ qualified personnel for the construction work; hire an independent environmental checker (IEC); and make available the monitoring data on the Internet for public inspection. DEP, with the consent of the Secretary for the Environment and Food, could suspend the environmental permit or issue a cessation order if the works concerned violated the permit conditions and had resulted in environmental damage. On the enforcement front, the Environmental Protection Department was going to enhance manpower in 2002 to strengthen site inspection. In addition, EPD also planned to tighten the control of IEC.

35. In response to a Member's enquiry, Mr. Au said that the Council could propose a condition to require the project proponent to report to the Council regularly on the progress of the EM&A work and the findings.

EIA Subcommittee Secretariat
February 2002