The Drainage Services Department planned to open the waterfront promenade of To Kwa Wan Sewage Treatment Works to the public. The exterior wall of the building will be painted with a vast image of ‘Drainy’, the mascot of the Department. There will be several ‘Drainy’ 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.