Upgrading works necessary

I REFER to the letter from Mr Sunning Leung (South China Morning Post, July 20), in which he expressed concern over the removal of trees as a result of slope works near the entrance of Lion Rock Tunnel on the Sha Tin side.

These slopes, some of which were previously covered with chunam, have a history of slope failure and require upgrading works to improve their stability.

Mr Leung's concern that the tree cover should be preserved as far as possible is appreciated and is in line with the policy of the Geotechnical Engineering Office of the Civil Engineering Department, who are the designers of the landslip preventive works.

Apart from the lower portion of the slope, which is too steep to retain vegetation cover, the newly formed cut slope surfaces are being covered with a mixture of grass and tree seeds so that the area will be restored to a natural form in the long term.

Mr Leung may be assured that the appearance of finished slope works is a primary consideration in the choice of slope upgrading scheme adopted, and that includes the provision of vegetation cover where ever possible.

D. J. CRAIG Chief Geotechnical Engineer/Design Geotechnical Engineering Office Civil Engineering Department