Hong Kong airport builds third runway with strategy to help marine environment thrive
When Hong Kong International Airport (HKIA) set out to build a new runway and associated facilities for the three-runway system operation, engineers had to carefully navigate a challenge hidden beneath the surrounding waters. The project involved 650 hectares (1,606 acres) of reclaimed land adjacent to the existing airport, an area equivalent to about 34 Victoria Parks or 900 standard football…
Hong Kong International Airport (HKIA) embarked on a mission to construct a new runway and associated facilities for a three-runway system, all while ensuring the protection and enhancement of the surrounding marine environment. The project involved the development of 650 hectares of reclaimed land, which is equivalent to 34 Victoria Parks or 900 standard football pitches.
However, 40% of this land lay above contaminated mud pits from earlier construction works, posing a significant challenge for conventional reclamation methods that involve dredging and the release of legacy pollutants into the marine environment.
To address this issue, the Airport Authority opted for deep cement mixing, a novel technique that injected cement slurry directly into the seabed, hardening it into more than 360,000 columns. This approach not only contained the contaminants but also consolidated the soft material simultaneously. The use of deep cement mixing not only safeguarded the marine environment but also saved approximately a year of settlement time and reduced the fill material demand by about 10%.
This environmentally conscious strategy also extended to other aspects of the project. For instance, horizontal directional drilling was employed to install aviation fuel pipelines nearly 100 meters below the seabed, avoiding the need for dredging a trench. This technique set a world record for the longest pipeline installation using low-impact construction.
Moreover, the project incorporated over 250 measures to mitigate potential environmental impacts during construction and operation. The 13km sea wall surrounding the reclaimed land featured more than 500 eco-enhanced blocks, which mimicked natural rock pools to attract marine life. The Airport Authority also installed 600 artificial reefs and released nearly 90,000 fish fry into the surrounding waters.
Furthermore, the 2,400-hectare North Lantau Marine Park, the largest and newest of its kind in Hong Kong, was designated, bolstering the protection and enhancement of marine biodiversity in the region.
Written by urgent.news from South China Morning Post - Hong Kong's reporting — not their text. Machine-written — may contain errors; check the original before relying on it.
