Flooding on 10 February affected Sydney, Camden, Lismore, Taree and Moruya, resulting in six deaths. The flood accompanied severe storms that affected the Sydney, Newcastle and Wollongong regions on 10 and 11 February. 

The Hawkesbury River recorded a height of 14.31 m at the Windsor Bridge (NOTE: a new gauge at Windsor Bridge reduced measurements by 30.5 cm). The flooding caused main evacuation routes to be closed and loss of power to Richmond and Windsor including west of the Hawkesbury River. The McGraths Hill sewerage plant was interrupted; electricity cut to Hawkesbury-Nepean Valley's low lying areas, including widespread power blackouts through flood bound areas of the State.

The Insurance Council of Australia estimated the 1978 damage at $15 million, with the 2011 estimated normalised cost of $215 million.