Lewisham Sewage Aqueduct, Heritage sewerage aqueduct in Summer Hill, Australia.

The Lewisham Sewage Aqueduct carries an oviform steel plate pipe, 1.4 by 1.1 metres, across a shallow valley on mass concrete piers faced in worked sandstone. The riveted carrier rests on rocker supports and terminates in stone-faced abutments; four concrete arches of about 2.4 metres span sit within each embankment.

Design work for the aqueduct was finished by March 1897 under Joseph Davis, engineer-in-chief of the Public Works Department's Sewerage Branch. Piers stood and steel plates had arrived by mid-1898, and the Dobroyd Branch was completed by mid-1900 and handed to the Water Board. It was listed on the New South Wales State Heritage Register on 18 November 1999.

The structure represents a milestone in Sydney's urban development, demonstrating the advancement of public health infrastructure in early twentieth-century Australia.

The aqueduct stands in Gadigal Reserve beside 5 Grosvenor Crescent, Summer Hill, in a shallow valley north of the main western railway line. The stormwater channel passes between Piers 2 and 3, and the railway viaduct and embankment run alongside, so the carrier, piers and channel can be seen together from the reserve. The tallest pier is about 7.3 metres.

The pipes have an unusual oval shape that was specifically designed to handle wastewater flow more efficiently. This design approach was innovative for its time and reflects the engineering knowledge of that era.