
AAHK's "triple water system" helps reduce the airport’s freshwater demand by over 50% each year.
Hong Kong International Airport (HKIA) is well equipped with large-scale water-saving facilities, and Airport Authority Hong Kong (AAHK) implements a number of measures to minimise daily water usage.

HKIA adopts a "triple-water system" designed to minimise freshwater use at the airport.
Seawater is used for flushing toilets and as the cooling medium in the air-conditioning systems of major airport buildings, substantially reducing freshwater demand.
Meanwhile, wastewater from terminal kitchens, washroom sinks, and aircraft catering and cleaning activities is collected through a greywater collection system and then processed in an on-site wastewater treatment plant for reuse in airport landscape irrigation.
This "triple-water system" approach helps reduce HKIA’s freshwater demand by over 50% annually.
Details of AAHK's water management performance are available in our latest Sustainability Report.

AAHK implements various measures to manage cooling water and storm water discharges. These include:
AAHK regularly monitors HKIA’s impact on the marine environment caused by storm water discharges and construction activities. Monitoring results show that cooling water and storm water discharges from the airport do not have adverse impacts on local water quality.

In 2019, AAHK approved Hong Kong Aircraft Engineering Company Limited (HAECO) and China Aircraft Services Limited (CASL) to carry out dry wash on the maintenance apron at HKIA. Aircraft dry wash is a technique that uses little or no water in cleaning the aircraft. Compared with wet wash, dry wash is estimated to consume 90% less water and produces less effluent.
AAHK has also worked with airport business partners to develop Dry Wash Procedures to ensure cleaning processes are performed in accordance with all environmental, health and safety requirements.