LCQ13: Road safety involving roadside trees
22.4.2020

Following is a question by the Hon Chan Hak-kan and a written reply by the Secretary for Development, Mr Michael Wong, in the Legislative Council today (April 22): Question: It is learnt that there have been, from time to time, incidents of vehicles damaged (e.g. cracking of the windowpanes of franchised buses) or traffic accidents, resultant from vehicles hitting roadside trees, the trunks and branches of these trees that overhung the roads or their wilted branches that fell onto the roads. In this connection, will the Government inform this Council: (1) of the number of complaints received by the authorities in each of the past five years about roadside trees posing hazards to road safety, and the details of the follow-up actions; (2) of the number of traffic accidents caused by vehicles hitting roadside trees or their trunks and branches that overhung the roads, and the resultant casualties, in each of the past five years; (3) of the mechanism currently put in place to prevent roadside trees from posing hazards to road safety; the respective numbers of roadside trees that were pruned and removed by the authorities in the past three years; (4) whether the authorities will designate a single government department to take up the task of managing roadside trees; if so, of the details; if not, the reasons for that; (5) how the authorities currently determine the species of the trees to be planted alongside the roads; (6) whether, in the light of a serious traffic accident that occurred on Fanling Highway in December last year and involved a bus hitting a tree, the authorities have reviewed the road safety measures of the location concerned so as to avoid the occurrence of similar incidents; if so, of the details; (7) as the front left compartment on the upper deck of a bus is the first to bear the brunt when the bus hits the trunks and branches of roadside trees, whether the authorities have discussed with bus companies the adoption of improvement measures to enhance the protection for passenger safety; if so, of the details; (8) given that there is a shortage of local workers in the greening industry, of the authorities' new measures to attract new blood to the industry with a view to improving tree management work; and (9) given that the arboriculture and horticulture industry is not regarded as a separate trade in the construction industry, and that a registration system for arboriculture and horticulture practitioners has not been set up at present, of the improvement measures put in place by the authorities to ensure the quality of tree management work? Reply: President, The Government is committed to the proper management of tree assets to ensure healthy tree growth and with public safety as the prime consideration. In respect of the nine-part question raised by the Hon Chan Hak-kan, our reply, upon consultation with relevant departments, is as follows: (1) In the past five years, as regards complaints about roadside trees affecting road safety, government departments received 1 937 cases in 2015, 3 840 cases in 2016, 4 672 cases in 2017, 7 513 cases in 2018 and 3 187 cases in 2019. Upon receipt of complaints, relevant departments would take immediate follow-up actions having regard to the health, structural and growth conditions of the trees. These actions include assessing the tree risks and implementing appropriate risk mitigation measures, such as pruning, removing wilted branches, controlling pests and diseases; cordoning off dangerous trees; and removing hazardous trees that pose an imminent threat to the life and property of road users. (2) Based on the records of the departments concerned, the numbers of traffic accidents and resultant casualties involving "vehicle crashing into trees" from 2015 to 2019 are tabulated below. These traffic accidents mainly involved driver contributory factors, including "driving inattentively" and "loss of vehicle control".&emsp; Year Number of traffic accidents Casualties Fatal Serious injury Minor injury 2015 45 1 16 53 2016 53 1 12 63 2017 45 1 11 56 2018 49 1 11 58 2019 â38 6 10 76 Government departments regularly send their teams to inspect trees along public roads and on expressways (including roadside vegetation) under their purview, and record whatever damages to road facilities and potential hazards. In case there are overgrown branches obstructing traffic flow, blocking sightline, blocking traffic lights or signs, or posing potential impact on vehicles, etc., the departments will immediately arrange branch pruning or tree removal as soon as practicable to keep road users safe. In addition, government departments also undertake annual inspections and risk assessments on trees under their purview, so as to carry out the necessary tree maintenance works in due course, including controlling pests and diseases, pruning and removing branches or the whole trees that pose threat to public safety. Since pruning and removal of roadside trees are part of departments' overall tree management work, no breakdown of such work is available. (4) As there are numerous roadside trees in Hong Kong and their geographical distribution is wide, designating a single government department to take up the task of managing all roadside trees is not the most effective way in resource deployment. The Government adopts an "integrated approach" in conserving and managing our tree assets, under which departments responsible for maintaining the government facilities or land allocated to them are responsible for taking care of the trees thereon in accordance with the requirements and guidelines promulgated by the Development Bureau (DEVB). This approach allows departments to carry out appropriate routine tree maintenance having regard to the specific characteristics and locations of the trees. (5) As regards the selection of roadside tree species, departments will follow the principles of "Right Tree, Right Place" and vegetation diversity advocated by DEVB, consider the site conditions and constraints (such as planting space, microclimate, underground and aboveground utilities, traffic and pedestrian flow, sightline impact, etc.), landscape design, planting purposes and functions, ecological issues, as well as the characteristics and maintenance requirements of different tree species, and make reference to the Street Tree Selection Guide issued by DEVB. (6) After the relevant accident, the Transport Department (TD) has reviewed the design of the road section concerned, namely, Fanling Highway Sheung Shui bound near Tsung Pak Long. The road section concerned is a dual three-lane expressway with posted speed limit of 100 km/hr. Hard shoulders and barriers are provided on both sides of the road, and their design complies with the road safety standards. (7) Following the serious bus accident last December, TD took further follow-up actions to enhance bus safety with all franchised bus operators. As requested by TD, the franchised bus operators have expedited the installation of advanced driver assistance systems (including collision avoidance and lane keeping alert systems) on their buses, with a view to having the devices installed on all franchised buses operating the airport routes and/or via expressways by Q4 2020. In addition, TD has explored with major bus manufacturers and franchised bus operators the need, feasibility and implications on enhancing the bus structure (especially the upper deck) so as to provide additional protection for upper-deck passengers. In light of Hong Kong's special circumstances, the major bus manufacturers have embarked on impact analysis by computer simulation to further assess the strength and integrity of the existing structure of franchised buses, and explore structural enhancement measures accordingly. TD will continue to closely follow up with major bus manufacturers on possible improvement measures related to bus structure and other vehicle technology. (8) The Financial Secretary announced in the 2019-20 Budget the setting up of a $200 million Urban Forestry Support Fund (the Fund) to encourage youngsters to join the arboriculture and horticulture industry, uplift the professional standards of the practitioners, and strengthen public education and promotion on proper tree care. Upon funding approval by the Legislative Council, the Fund will support DEVB in rolling out various new initiatives, including introduction of the Study Sponsorship Scheme and the Trainee Programme, hosting International Urban Forestry Conferences, as well as holding many more education and promotion activities in collaboration with local groups. Among these new initiatives, the Study Sponsorship Scheme and the Trainee Programme will help address the issue of manpower shortage within the arboriculture and horticulture industry. (9) As announced in the Policy Address Supplement on October 16, 2019, DEVB will introduce a registration scheme for tree management personnel, with a view to enhancing the quality of the tree management personnel, the professional standards of the industry and the practices of tree management work. In the interim, in 2019, DEVB updated the "Guidelines for Tree Risk Assessment and Management Arrangement", increased the audit percentage of risk assessment reports, and set up a dedicated Inspection Squad which aims to adopt a systematic approach to randomly check and audit the tree inspection reports completed by the tree management departments, and proactively inspect trees in areas of high pedestrian and vehicular traffic flow to ensure that departments adhere to the Guidelines. Besides, before the onset of the typhoon and rain season every year, DEVB reminds private property owners and property management personnel to undertake risk assessment on the trees within their property and implement appropriate mitigation measures in a timely manner. We also organise tree management workshops for private property management personnel from time to time to strengthen their awareness on proper tree care.