I was amazed to learn of the recent discovery of a historic underground balance water tank at a now-defunct service reservoir in Sham Shui Po (“ Hong Kong authorities suspend demolition of striking century-old structure ”, December 28). The balance tank, featuring a series of arches built of granite and red bricks and aqueduct dated 1909, was discovered during demolition work of the service reservoir on top of Bishop’s Hill. The structure could be one of the earliest public works of the New Kowloon area, following the lease of the New Territories to Britain in 1898. There is no lack of well-preserved pre-war waterworks that, as declared monuments, bear considerable aesthetic and historical significance throughout Hong Kong, from hiking trails to recreational grounds. The Sham Shui Po service reservoir, if well maintained, could be an invaluable asset for the community. The historic site has been saved from the bulldozers for now and I welcome the decision to suspend the demolition work on Bishop’s Hill. I also urge the authorities to declare the balance tank a proposed monument. In the meantime, plans should be prepared to study the history of the water work, ascertain an official historic building grading and preserve the site for the public’s enjoyment. Ben L. Tsang, Yuen Long