Following is a question by the Hon Chan Hak-kan and a written reply by the Secretary for Development, Mrs Carrie Lam, in the Legislative Council today (July 7):
It has been reported that the Development Bureau revealed in early June this year that after inspections conducted by a number of government departments, it was found that the health of the majority of the trees in Hong Kong was in normal conditions, but about 2,000 of them required further detailed inspection. Subsequently, a tree-falling accident occurred in Yuen Chau Kok Park, Sha Tin, on June 14 this year, causing the death of a male passer-by, which has aroused concern of the community about the issue of tree management and caring. In this connection, will the Government inform this Council:
(a) of a breakdown, by the name of government departments, of the respective numbers of trees under the custody of the relevant departments at present, the number of trees in need of further inspection, and the manpower involved, as set out in the following categories:
2) Manpower responsible for tree management under its custody (general staff and those who are certified arborists);
3) Number of trees under its custody;
4) Number of trees which require further detailed inspection;
(b) of the specific information required to be filled in by various government departments at present after finishing visual inspections of the trees under their custody, so as to facilitate follow-up actions in the future; whether various government departments currently prepare visual inspection reports in an uniform format; if not, of the reasons for that, and whether the Tree Management Office under Development Bureau will consider requiring the various departments to use a uniform format;
(c) whether Tree Management Office has drawn up arrangements for further inspection of trees; if so, of the details (including the specific procedure for further inspection and the percentage of trees to be further inspected);
(d) given that the typhoon season is approaching, whether the various government departments will expedite the process for further inspection of trees; if so, how they will complement the work in terms of manpower; if not, of the reasons for that, and what short-term measures are in place, so as to avoid the recurrence of tree-falling incidents; and
(e) given that Development Bureau is conducting a study on the establishment of a database of important or problematic trees, when the study is expected to be completed; what information will be included in the database, and whether it will be made public for information?
The Task Force on Tree Management led by the Chief Secretary for Administration published the Report of the Task Force on Tree Management – People, Trees, Harmony in June last year. Pursuant to the recommendations of the Report, the Development Bureau in conjunction with the tree management departments implemented the tree risk assessment arrangements in January this year.
Tree risk assessment is conducted step-by-step in two stages. In the first stage which involves an "area basis" assessment, the departments first identify those areas with high pedestrian or vehicular flow under their management. In the second stage involving a "tree basis" assessment, the departments carry out visual assessment for tree group inspections at locations with high pedestrian or vehicular flow in accordance with a systematic methodology and procedures.
During tree group inspections, the departments will identify trees that may need particular care, such as Old and Valuable Trees and stonewall trees, as well as dead trees and trees with major health or structural problems that may pose hazards to the public. Then detailed inspections, including visual assessment, will be conducted for these trees individually. Subject to the specific condition of the trees (e.g. when it is necessary to ascertain whether there is internal rot or tree cavity), further inspections using equipment (e.g. resistograph or sonic tomograph) will be conducted where necessary for assessing the improvement measures required. This assessment methodology has made reference to internationally recognised best practices.
After the tree management departments have completed tree group inspections, they have identified about 2,000 trees requiring detailed inspections.
My reply to the question raised by Hon Chan Hak-kan is as follows:
(a) The number of trees under the purview of the tree management departments, the manpower involved in tree management, and the number of trees requiring detailed inspection as identified in the aforementioned tree group inspections are set out in the Annex.
(b) According to the guidelines issued by the Tree Management Office of the Development Bureau, tree management staff are required to keep records of tree group inspections as well as detailed inspection of individual trees. Tree group inspection records contain mainly basic information on tree groups such as location, tree species, tree height, tree age group, and general health and structural condition of the tree group; trees identified as requiring particular care (such as Old and Valuable Trees and stonewall trees), or dead trees and trees with major health or structural problems which may pose hazards to the public; and recommended follow-up measures on trees with problems. Detailed inspection records for individual trees contain details of the trees inspected such as location, tree species, basic overall condition of the trees, tree crown condition, branch condition, trunk condition, root condition, people or property that may be affected by the trees if fallen, tree risk assessment and recommended follow-up measures for risk mitigation. In setting the above requirements for inspection records, the Development Bureau has made reference to internationally recognised best practices.
Some tree management departments (such as the Agriculture, Fisheries and Conservation Department, the Leisure and Cultural Services Department, the Housing Department and the Highways Department) have previously drawn up their own tree inspection record format. According to information provided by the departments, the content of their inspection records are broadly consistent with the guidelines issued by the Tree Management Office. The Tree Management Office will, in conjunction with the tree management departments, examine whether a standardised record format should be adopted.
(c) The Tree Management Office has enhanced inspection of tree risk management work carried out by the tree management departments. This includes, among others, random inspection of the tree inspection records completed by departmental staff and random inspection on site of the condition of trees under the care of individual departments. For cases where outstanding follow-up actions are identified, the Tree Management Office will urge the departments to take early action and will provide, where necessary, professional advice. According to the action plan of the Tree Management Office, random inspections on site totalling 52 man-days (including preparation of pre-inspection information and post-inspection records as well as referral of cases to relevant departments for follow-up) have been completed as at July 6 this year. The random inspection cases cover all 18 districts across the territory with special emphasis on locations with high pedestrian or vehicular flow. The inspections are conducted by staff with professional arborist qualifications.
(d) Tree risk assessment is not a one-off exercise. It needs to be carried out continuously as part of day-to-day tree maintenance work. As living organisms, trees face the natural cycle. They grow, age, become weak and die. Their health and structural conditions change with time and their surroundings, and especially in bad weather. The tree maintenance departments will closely monitor the conditions of trees during the typhoon and rainy season. Should there be any change in the risk level, immediate follow-up action will be taken. In addition, to further enhance tree risk management, the Development Bureau has agreed with the tree management departments on the following improvement measures:
- First, the departments should ensure that all day-to-day tree management work is conducted in a professional and careful manner. They should also adopt measures to ensure the quality of their work through, for example, close supervision of frontline work and internal audit.
- Second, all departments should handle tree complaint cases promptly so as to identify problematic trees as soon as possible and take necessary follow-up actions.
- Third, the Tree Management Office has enhanced monitoring of tree management work carried out by departments. This includes, among others, random inspection of the tree inspection forms completed by the departments and random inspection on site of the condition of trees under the care of individual departments.
- Fourth, the tree management departments will closely monitor the conditions of trees during typhoon and rainy season. Should there be any change in the risk level, immediate follow-up actions will be taken. In the light of the circumstances and where there are no other feasible risk mitigation measures, trees will be removed as a last resort so as to eliminate the threat to public safety.
- Fifth, enhancement of training. The Tree Management Office has provided training courses to over 2,230 government staff and contractor staff following the implementation of tree risk assessment arrangements early this year. The Tree Management Office will continue to arrange more training for the tree management departments in the light of their operational needs. It will also encourage staff of various levels to obtain professional qualifications in arboriculture, with a view to generally raising the professional standard of tree management staff.
(e) The Development Bureau, together with the tree management departments, is now collating information on trees which have undergone detailed inspections in recent months with a view to releasing information on trees for which the tree management departments have carried out detailed inspections but the improvement measures for which have not yet been completed as well as trees requiring special attention (e.g. Old and Valuable Trees and stonewall trees) to the public in an appropriate manner in the middle of this month.
Ends/Wednesday, July 7, 2010
Issued at HKT 16:23