The Drainage Services Department has opened the waterfront promenade of To Kwa Wan Sewage Treatment Works to the public. The exterior wall of the building was painted with a vast image of ‘Drainy’, the mascot of the Department. Several ‘Drainy’ were installed along the promenade, and their hats can also be used as tables. The concept of sustainability blends well with the design. The bioswale at the entrance garden can collect stormwater for irrigation, the wind turbines can help to generate electricity, and the existing green wall is retained.