In the late 1940s the lanes on the bridge were reconfigured to provide a third lane, and this allow the introduction of a tidal flow system (northbound in the morning and southbound in the evening), which continued until the second bridge was opened. Notwithstanding the creation of the third lane, by the mid 1960s congestion had grown to a significant level, especially on summer weekend afternoons. However it was not for another twenty years that funding was allocated by the New South Wales government for the design and construction of a duplicate bridge.