The Mooki and Namoi Rivers of northern New South Wales join immediately upstream of Gunnedah. A considerable portion of the flood plain of these two rivers is utilised for irrigation, which has resulted in changes in land use and various earthworks which have influenced natural drainage and flooding patterns. The objectives of the Namoi Valley Guidelines for Floodplain Development are to:

• identify all works within the study area and their possible impacts on flooding and associated drainage,
• provide a plan and series of options consistent with the agreement of the land-holders within the Carroll group which will prevent any adverse impact by the works on flooding and associated drainage,
• propose a mechanism for co-ordinating earthworks within the Carroll group and neighbouring groups,
• ensure works will be consistent with Part VIII of the Water Act, and to
• give consideration to the environmental impact of the existing and proposed development with special consideration to the Environment Protection Authority (EPA) Clean Waters Act and the Riverine Corridor policy and procedures.