The town of Bourke on the Darling River in New South Wales has a population of about 3,600 and is protected from flooding by a 10km levee surrounding the town.

The levee was constructed and raised in several phases work generally being initiated by approaching floods. Under these conditions construction and raising occurred with some urgency and high standards of construction cannot be relied upon.

In 1985 Bourke Shire Council commissioned Sinclair Knight and Partners to undertake a study of the Bourke levee system with a view to assessing the condition of the existing levee and determine appropriate means of augmentation of the levee. Included in this study was a geotechnical investigation into the condition of the existing levee, investigation into the suitability of component materials and design of a revised levee carried out by Coffey and Partners.

With the approach of the 1990 floods an urgent inspection was organised for the PWD and DWR to assess the integrity of the existing levee and to recommend areas which might be rectified within the available time before the arrival of the floods. This report identified general deficiencies in the levee system and provided preliminary designs for corrective works. Despite the documented deficiencies in the levee system the town of Bourke has to date not been inundated as a result of failure of the levee.