Band of hydrographers quietly work under water to ensure developments in Hong Kong go smoothly
They carry out critical marine work that is vital for the building of major infrastructure and to keep the city going
In space-starved Hong Kong, the availability of land for housing and commerce is a constant obsession, to the extent that most people tend to forget about the sea and its importance for the city’s development.
Nearly two-thirds of Hong Kong’s total area is under water, but few are aware of how much critical marine work is involved in infrastructure development and keeping the city going, except for a niche profession of hydrographic surveyors who specialise in offshore mapping.
They regularly head out to sea on vessels equipped with high-tech sonar gear to scan the seabed, collecting data on geological features such as submerged rock and coral formations, the depth of the water and the composition of the seabed. The data is then charted and updated on maps.
But hydrographers do more than just mapping the 1,648 sq km of surface water. Major infrastructure projects taking in the sea – from the three cross-harbour tunnels to the planned HK$141 billion third airport runway – would not be possible without their work.
“Everything from the airport, tunnels and bridges, anything built on water, requires surveying to see where the best location to build it would be,” said Matthew Lai Wing-cheung, director of EGS, an international surveying company based in Hong Kong.