The city’s heritage conservation approach has again come under the spotlight in the wake of the near-demolition of a magnificent century-old underground reservoir in the heart of Kowloon. Recent inspections by heritage lovers on Hong Kong Island also showed that the aqueduct of the city’s oldest reservoir has not been given the protection it deserves. The authorities are facing growing calls to reassess the historic structures before they fall into ruin. Only a section of the conduit at Pok Fu Lam reservoir has been given a grade two status in recognition of its “special merit”. More than a dozen of the original 32 sections are still intact but with no protection, according to Paul Zimmerman, a Southern district councillor and CEO of Designing Hong Kong. A campaign calling for full conservation for the aqueduct is gathering momentum. Admittedly, many of these arched stone structures are tucked away at the hillside and are nowhere as impressive as the Romanesque pillars unearthed at Bishop Hill reservoir last month. But they are an integral part of the Pok Fu Lam conduit that is still in use after more than a century. The section that made it into the city’s original 1,444 historic structures is described as “an interesting example of late Victorian waterworks engineering”. Indeed, other historic structures associated with the reservoir, such as the gauge basin, masonry bridge, the watchman’s cottage and the box culvert, are declared monuments or graded structures. Given the historic value of the water facilities to the city’s development, a holistic appraisal makes sense. As heritage experts said, the significance of the aqueduct comes from the entire span rather than a section being visually outstanding. The city’s conservation approach has long been branded as half-hearted. There were examples of architectural complex assessed in a piecemeal manner and structures overlooked until demolition works stirred public outrage, as in the case of the Bishop Hill reservoir. The project was only halted after images of bulldozers flattening the unusual site went viral on social media and prompted officials to apologise for the oversight. The authorities should learn the lesson and widen the assessment.