North Sydney Sewer Vent, Heritage-listed sewer ventilation stack in North Sydney, Australia

North Sydney Sewer Vent is a brick ventilation stack built as part of the original sewerage system to let air flow through underground pipes. The structure tapers narrower toward the top and is reinforced with visible steel hoops that hold it together.

This vent stack was built between 1891 and 1898 as part of the original sewerage system for North Sydney. It survived many decades until damage occurred during expressway construction in the 1960s, after which steel reinforcement was added.

The vent is also known as the Alfred St Sewer Vent, and oral history records that foul odours once permeated the area before the Bradfield Highway was built. Complaints may have led to the removal of its original pagoda-like dome. Odours are still detectable under certain climatic conditions.

The stack sits on a street in North Sydney and can be easily reached on foot in the area. It is best viewed from the street as it continues to serve its original function as part of the sewerage system.

At the base sits an iron inspection hatch marked with a plaque from 1899 by the Metropolitan Board of Water Supply and Sewerage. This small detail reveals the careful craftsmanship put into what was once routine city infrastructure.